BR112015011910B1 - DECODING DEVICE AND METHOD, ENCODING DEVICE, AND, COMPUTER READABLE MEDIA - Google Patents

Abstract

DECODING DEVICE AND METHOD, ECODING DEVICE, AND COMPUTER READABLE MEDIA A decoding device is provided including circuitry configured to receive encoded data and conversion information, the encoded data belonging to a picture having luminance in a first dynamic range and the conversion information pertaining to a dynamic range conversion of the image luminance of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function.

Description

CROSS-REFERENCE TO RELATED ORDERS

[001] This application claims the benefit of Japanese Priority Patent Application JP 2013-215060 filed on October 15, 2013, Japanese Priority Patent Application JP 2013-272945 filed on December 27, 2013, and Japanese Priority Patent Application JP 2013-272945 filed on Japanese Priority JP 2014042174 filed March 4, 2014, the entire contents of each of which are incorporated herein by reference.

Technical Field

[002] The present description relates to a decoding device and a decoding method, and an encoding device and an encoding method, and particularly to a decoding device and a decoding method, and an encoding device and an encoding method. an encoding method capable of converting a decoded image into a desired image with a different dynamic range.

Background of the Invention

[003] In recent years, devices conforming to a method such as Expert Group Moving Pictures (MPEG) have been spread widely for both delivering information at broadcast stations or the like and receiving information in homes. MPEG compresses the image information by orthogonal transform such as discrete cosine transform and motion compensation using unique redundancy for the image information.

[004] In particular, an MPEG2 method (ISO/IEC 13818-2) is defined as a general-purpose image encoding method, and is currently widely used in extensive applications for professional use and consumer use as a standard covering both. an interlaced scan image and a progressive scan image, and a standard resolution image and a high definition image. By using the method of MPEG2, it is possible to realize a high compression ratio and good image quality, for example, assigning a bit rate of 4 Mbps to 8 Mbps for an interlaced raster image of a standard resolution having 720 x 480 pixels and assigning a bitrate of 18 Mbps to 22 Mbps for an interlaced raster image of a high resolution having 1920 x 1088 pixels.

[005] MPEG2 mainly aimed at encoding high picture quality suitable for broadcasting, but did not operate a method of encoding at a lower bit rate than that in MPEG1, that is, at a higher compression ratio. With the widespread use of handheld terminals, the desire for such an encoding method was seen to increase, and so an MPEG4 encoding method was standardized to match this. Regarding an MPEG4 image encoding method, a standard thereof was approved as an international standard entitled ISO/IEC 14496-2 in December 1998.

[006] Furthermore, in recent years, standardization of a standard called H.26L (ITU-T Q6/16 VCEG) has progressed towards the original purpose of image encoding for videoconferencing use. H.26L uses a larger calculation amount due to encoding and decoding than related art encoding method such as MPEG2 or MPEG4, but it is known to realize higher encoding efficiency.

[007] Additionally, as part of MPEG4 activities, Enhanced Compression Video Coding Suite Model is currently being standardized in order to realize higher coding efficiency by also incorporating functions that are not supported by H.26L, on the basis of H.26L .26L. As for the standardization program in addition, the encoding method became an international standard under the name of H.26L and MPEG-4 Part 10 ((Advanced Video Coding (AVC)) in March 2003.

[008] In addition, as an extension of the AVC method, Fidelity Range Extension (FRExt) which includes encoding tools for business use such as RGB or YUS422 and YUV444 and also includes DCT 8x8 or quantization matrix defined in MPEG2 was standardized in February 2005. This realizes an encoding method in which even film noise included in a movie can be expressed favorably using the AVC method, and thus leads to use for various applications such as a Blu-ray disc. (BD) (registered trademark).

[009] However, recently, there have been increasing demands for higher compression ratio encoding, such as a demand to compress an image of about 4000 x 2000 pixels, which is four times the size of a high-vision image or a demand for delivery of a high vision image in circumstances of limited transmission capacity such as the Internet. For this reason, coding efficiency improvement study is currently being performed in the Video Coding Expert Group (VCEG) affiliated to the former ITU-T.

[0010] In addition, currently, for the purpose of improvement in coding efficiency higher than that of AVC, standardization of a coding method called High Efficiency Video Coding (HEVC) is in progress by the Joint Collaboration Team - Video Coding (JCTVC), which is a joint ITU-T and ISO/IEC standardization organization. NPL 1 was currently published as a draft in August 2013.

[0011] Meanwhile, recently, with the progress of techniques, a high dynamic range (HDR) display with the maximum luminance of 500 nit or 1000 nit has started to be sold in the market.

[0012] In a case where a standard dynamic range (SDR) display and an HDR display are mixed, it is necessary to encode each of an SDR image and an HDR image in the AVC method or in the HEVC method, and thus an amount of data increases. Therefore, a method is considered in which the SDR image and the HDR image are encoded, and then one dynamic range is converted after decoding is performed as necessary, thereby generating the other. Citation List Non-Patent Literature NPL 1 Benjamin Bross, Gary J. Sullivan, Ye-Kui Wang, "Editors' proposed corrections to HEVC version 1", JCTVC-M0432_v3, 18-4/26/4/2013.

Summary Technical problem

[0013] However, conversion into an image that is intended by a producer is not considered when converting a dynamic range is converted.

[0014] It is desirable to convert a decoded image into a desired image with a different dynamic range.

Solution to the Problem

[0015] According to an embodiment of the present description, a decoding device is provided including: circuitry configured to receive encoded data and conversion information, the encoded data belonging to a picture having luminance in a first dynamic range, and the information conversion pertaining to a dynamic range conversion of the image luminance of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function.

[0016] A decoding method of making a decoding device perform: receiving coded data and conversion information, the coded data belonging to a picture having luminance in a first dynamic range and the conversion information belonging to a dynamic range conversion of image luminance of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function.

[0017] An encoding device including: circuitry configured to establish conversion information pertaining to a dynamic range conversion of a luminance of an image of a first dynamic range into a second dynamic range; and encoding the image having luminance in the first dynamic range to generate encoded data, wherein the conversion uses a knee function.

[0018] A non-transient computer-readable medium having encoded data and conversion information stored therein, the encoded data belonging to an image having luminance in a first dynamic range and the conversion information belonging to a dynamic range conversion of the luminance of the image of the first dynamic range into a second dynamic range, wherein a decoding device decodes encoded data, generates the image based on the decoded data, and converts the dynamic range based on the conversion information including an elbow.

[0019] According to an embodiment of the present description, there is provided a decoding device including an extraction unit that extracts coded data and conversion information from a coded stream including the coded data of a first picture, which is a picture having luminance into a first dynamic range and conversion information relating to the conversion of a dynamic range of the image luminance of the first dynamic range into a second dynamic range; and a decoding unit that decodes the encoded data extracted by the extraction unit to generate the first image.

[0020] A decoding method according to an embodiment of the present description corresponds to the decoding device according to the embodiment of the present description.

[0021] According to an embodiment of the present description, encoded data and conversion information is extracted from an encoded stream including the encoded data of a first image, which is an image having luminance in a first dynamic range and the conversion information, which is information relating to converting a dynamic range of the image luminance of the first dynamic range into a second dynamic range, and the extracted encoded data is decoded so that the first image is generated.

[0022] According to another embodiment of the present description, an encoding device is provided including an establishment unit that establishes conversion information, which is information relating to the conversion of a dynamic range of luminance of an image from a first dynamic range into a second dynamic range; a coding unit that encodes a first image, which is the image having luminance in the first dynamic range so as to generate encoded data; and a transmission unit transmitting an encoded stream including the conversion information established by the setting unit and the encoded data of the first picture generated by the encoding unit.

[0023] An encoding method of another embodiment of the present description corresponds to the encoding device according to another embodiment of the present description.

[0024] According to an embodiment of the present description, conversion information is established, which is information relating to the conversion of a luminance dynamic range of an image from a first dynamic range into a second dynamic range, a first image which is the image having luminance in the first dynamic range is encoded so that encoded data is generated, and an encoded stream including the conversion information and encoded data of the first image is transmitted.

[0025] Furthermore, the decoding device and the encoding device according to the embodiments can be implemented by running a program on a computer.

[0026] Additionally, the program executed on the computer in order to implement the decoding device and the coding device according to an embodiment can be provided by transmitting the program on a transmission medium or recording the program on a recording medium.

[0027] The decoding device and the coding device according to embodiments can be independent devices, and can be an inner block forming a single apparatus.

Advantageous Effects of the Invention

[0028] According to an embodiment of the present description, it is possible to decode encoded data from an image. Furthermore, according to the embodiment of the present description, it is possible to convert a decoded image into a desired image with a different dynamic range.

[0029] According to another embodiment of the present description, it is possible to encode an image. Furthermore, according to another embodiment of the present description, it is possible to encode an image such that a decoded image can be converted into a desired image with a different dynamic range during decoding.

[0030] Furthermore, the effects described herein are not necessarily limited, and there may be any of the effects described in the present description.

Brief Description of the Drawings

[0031] Figure 1 is a diagram illustrating an SDR image.

[0032] Figure 2 is a diagram illustrating an HDR image.

[0033] Figure 3 is a diagram illustrating an overview of coding in an embodiment of the present description.

[0034] Figure 4 is a diagram illustrating a decoding overview in one embodiment of the present description.

[0035] Figure 5 is a diagram illustrating knee decompression.

[0036] Figure 6 is a block diagram illustrating an example configuration of an embodiment of an encoding device to which the present description is applied.

[0037] Figure 7 is a diagram illustrating a syntax example of knee_function_info SEI.

[0038] Figure 8 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 7.

[0039] Figure 9 is a diagram illustrating an example of conversion information set in the knee_function_info SEI.

[0040] Figure 10 is a diagram illustrating an example of conversion information set in the knee_function_info SEI.

[0041] Figure 11 is a flowchart illustrating a stream generation process performed by the encoding device.

[0042] Figure 12 is a block diagram illustrating an example configuration of one embodiment of a decoding device to which the present description is applied.

[0043] Figure 13 is a flowchart illustrating an image generation process performed by the decoding device of Figure 12.

[0044] Figure 14 is a diagram illustrating another syntax example of the knee_function_info SEI.

[0045] Figure 15 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 14.

[0046] Figure 16 is a block diagram illustrating a configuration example of a first embodiment of an encoding device to which an embodiment of the present description is applied.

[0047] Figure 17 is a diagram illustrating a first syntax example of knee_function_info SEI established by an establishment unit of Figure 16.

[0048] Figure 18 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 17.

[0049] Figure 19 is a diagram illustrating an example of DR conversion information from Figure 17.

[0050] Figure 20 is a diagram illustrating an example of DR conversion information from Figure 17.

[0051] Figure 21 is a flowchart illustrating a stream generation process performed by the encoding device of Figure 16.

[0052] Figure 22 is a block diagram illustrating an example configuration of a second embodiment of a decoding device to which the present description is applied.

[0053] Figure 23 is a flowchart illustrating an image generation process performed by the decoding device of Figure 22.

[0054] Figure 24 is a diagram illustrating another example of DR conversion information from Figure 17.

[0055] Figure 25 is a diagram illustrating yet another example of DR conversion information from Figure 17.

[0056] Figure 26 is a diagram illustrating an example of tone_mapping_info_SEI syntax including the DR conversion information from Figure 17.

[0057] Figure 27 is a diagram illustrating another example of tone_mapping_info_SEI syntax including the DR conversion information from Figure 17.

[0058] Figure 28 is a diagram illustrating a second syntax example of knee_function_info SEI established by the establishment unit of Figure 16.

[0059] Figure 29 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 28.

[0060] Figure 30 is a diagram illustrating an example of DR conversion information from Figure 28.

[0061] Figure 31 is a diagram illustrating an example of DR conversion information from Figure 28.

[0062] Figure 32 is a diagram illustrating an example of tone_mapping_info_SEI syntax including the DR conversion information from Figure 28.

[0063] Figure 33 is a diagram illustrating each piece of information set in the knee_function_info SEI of Figure 28 in a case where the number of elbows is restricted.

[0064] Figure 34 is a diagram illustrating an example of the knee_function_info SEI from Figure 28 in a case where the number of elbows is restricted.

[0065] Figure 35 is a diagram illustrating an example of the tone_mapping_info_SEI from Figure 32 in a case where the number of elbows is restricted.

[0066] Figure 36 is a diagram illustrating a third syntax example of knee_function_info SEI established by the establishment unit of Figure 16.

[0067] Figure 37 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 36.

[0068] Figure 38 is a diagram illustrating an example of DR conversion information from Figure 36.

[0069] Figure 39 is a diagram illustrating an example tone_mapping_info_SEI syntax including the DR conversion information from Figure 36.

[0070] Figure 40 is a diagram illustrating a fourth example of knee_function_info SEI syntax established by the establishment unit of Figure 16.

[0071] Figure 41 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 40.

[0072] Figure 42 is a diagram illustrating an example of DR conversion information from Figure 40.

[0073] Figure 43 is a diagram illustrating an example of DR conversion information from Figure 40.

[0074] Fig. 44 is a diagram illustrating a decoding device operation in a case where the knee_function_info SEI of Fig. 40 is set to a plurality.

[0075] Figure 45 is a diagram illustrating an example tone_mapping_info_SEI syntax including the DR conversion information from Figure 40.

[0076] Fig. 46 is a diagram illustrating an MP4 box in which DR conversion information is arranged.

[0077] Figure 47 is a diagram illustrating an example of ToneMapInfo syntax.

[0078] Figure 48 is a diagram illustrating that semantics in a first embodiment of a third embodiment of an encoding device to which the present description is applied is different from that in the second embodiment.

[0079] Figure 49 is a block diagram illustrating a first example of configuring one embodiment of a decoding system to which the present description is applied.

[0080] Figure 50A is a diagram illustrating an example of an elbow and knee conversion function defined by knee_function_info SEI that is received by the decoding system of Figure 49.

[0081] Figure 50B is a diagram illustrating an example of an elbow and knee conversion function defined by knee_function_info SEI that is received by the decoding system of Figure 49.

[0082] Figure 51 is a diagram illustrating an example of an approximate knee conversion function of Figure 50.

[0083] Figure 52 is a diagram illustrating an example of an approximate knee conversion function of Figure 50.

[0084] Figure 53 is a flowchart illustrating a decoding process performed by the decoding device of Figure 49.

[0085] Figure 54 is a flowchart illustrating a display process performed by a display device of Figure 49.

[0086] Figure 55 is a diagram illustrating an example syntax of knee_function_info SEI in a second configuration of the third embodiment of the coding device to which the present description is applied.

[0087] Figure 56 is a diagram illustrating a difference in semantics from Figure 55 of the second embodiment.

[0088] Figure 57A is a diagram illustrating an example of an elbow and knee conversion function defined by knee_function_info SEI of Figure 55.

[0089] Figure 57B is a diagram illustrating an example of an elbow and knee conversion function defined by knee_function_info SEI of Figure 55.

[0090] Figure 58 is a diagram illustrating an example of an approximate knee conversion function of Figure 57.

[0091] Figure 59 is a diagram illustrating an example of an approximate function of the knee conversion of Figure 57.

[0092] Figure 60 is a diagram illustrating an example syntax of approximate_knee_function_info SEI.

[0093] Figure 61 is a diagram illustrating a relationship between an electrical input signal and display luminance of a CRT.

[0094] Figure 62 is a diagram illustrating an electrical signal that is proportional to luminance.

[0095] Figure 63 is a diagram illustrating a relationship between an electrical input signal and display luminance.

[0096] Figure 64 is a diagram illustrating a function with a characteristic contrary to a function in Figure 61.

[0097] Figure 65 is a diagram illustrating an example of an image capture process flow until an image is displayed.

[0098] Figure 66 is a diagram illustrating OETF for use in an SDR image.

[0099] Figure 67 is a diagram illustrating OETF for use in an HDR image.

[00100] Figure 68 is a diagram illustrating an overview of a photoelectric conversion process in a fourth embodiment.

[00101] Figure 69 is a diagram illustrating an overview of an electro-optical conversion in the fourth mode.

[00102] Figure 70 is a block diagram illustrating a configuration example of the fourth embodiment of an encoding device to which the present description is applied.

[00103] Figure 71 is a flowchart illustrating a flow generation process performed by the encoding device of Figure 70.

[00104] Figure 72 is a block diagram illustrating an example configuration of the fourth embodiment of a decoding device to which the present description is applied.

[00105] Figure 73 is a flowchart illustrating an image generation process performed by the decoding device of Figure 72.

[00106] Figure 74 is a block diagram illustrating an example of a computer's hardware configuration.

[00107] Figure 75 is a diagram illustrating an example of a multipoint image encoding method.

[00108] Figure 76 is a diagram illustrating an example configuration of a multi-view image coding device to which the present description is applied.

[00109] Figure 77 is a diagram illustrating an example configuration of a multi-view image decoding device to which the present description is applied.

[00110] Fig. 78 is a diagram illustrating an example of a layer image encoding method.

[00111] Figure 79 is a diagram illustrating an example of spatially scalable coding.

[00112] Figure 80 is a diagram illustrating an example of a time scalable encoding.

[00113] Figure 81 is a diagram illustrating an example of scalable coding of an S/N ratio.

[00114] Figure 82 is a diagram illustrating an example configuration of a layer image coding device to which the present description is applied.

[00115] Fig. 83 is a diagram illustrating an example configuration of a layer image decoding device to which the present description is applied.

[00116] Figure 84 is a block diagram illustrating an example schematic configuration of a television set to which the present description is applied.

[00117] Figure 85 is a block diagram illustrating a schematic configuration example of a mobile phone to which the present description is applied.

[00118] Figure 86 is a block diagram illustrating an example schematic configuration of a recording/playback apparatus to which the present description is applied.

[00119] Figure 87 is a block diagram illustrating a schematic configuration example of an image forming apparatus to which the present description is applied.

[00120] Figure 88 is a block diagram illustrating an example of using scalable encoding.

[00121] Figure 89 is a block diagram illustrating another example of using scalable encoding.

[00122] Figure 90 is a block diagram illustrating yet another example of using scalable encoding.

[00123] Figure 91 is a diagram illustrating an example schematic configuration of a video device to which the present description is applied.

[00124] Figure 92 is a diagram illustrating an example schematic configuration of a video processor to which the present description is applied.

[00125] Figure 93 is a diagram illustrating another schematic configuration example of a video processor to which the present description is applied.

Description of Achievements Basis of Present Description SDR Image Description

[00126] Figure 1 is a diagram illustrating an SDR image.

[00127] As illustrated in Figure 1, an SDR image is, for example, an image whose image quality is adjusted to match a display device with a maximum luminance of 100 nit (candela per square meter). Since the maximum luminance in the natural system reaches 20000 nit or more in some cases, in the SDR image, a dynamic range of brightness is greatly compressed.

HDR Image Description

[00128] Figure 2 is a diagram illustrating an HDR image.

[00129] As illustrated in Figure 2, an HDR image is an image in which a dynamic range of luminance is greater than 0 to 100%. In the present specification, unless otherwise described, a dynamic range of an HDR image luminance is 0 to 400%. For example, as illustrated in Figure 2, in a case where an HDR image in which a dynamic range of luminance is 0 to 800% (800 nit) is encoded, and it is recorded on a Blu-ray disc (trademark) (BD) or similar, attribute information indicating luminance is also recorded along with the HDR image. Furthermore, attribute information is input to a display device together with a decoded HDR image, and the HDR image is displayed as an image in which a dynamic range of luminance is 0 to 800%.

[00130] Additionally, in a case where the maximum luminance of the display device is 1000 nit, for example, luminance of an HDR image is scaled to 1000 nit and displayed. Even in a case where grading is performed in this way, an HDR image has a dynamic range of luminance from 0 to 800%, and thus image quality deterioration thereof due to grading is less than that of an SDR image. .

First Modality Overview of Coding in the First Modality

[00131] Figure 3 is a diagram illustrating a coding overview in a first embodiment of a coding device to which the present description is applied.

[00132] In Figure 3, the transverse axis expresses a luminance value (input code value), and the longitudinal axis expresses luminance (output video level). Furthermore, the cross-axis luminance value of Figure 3 is a value obtained by setting the bitness of the luminance value to 10 bits and setting white luminance having undergone knee conversion to 100%, but a luminance value converted to luminance in practice is a value that is normalized to 0 or more and 1 or less. This is also the same for Figure 5 described later.

[00133] As illustrated in Figure 3, in the first embodiment, 80% to 400% of an HDR image in which a dynamic range of luminance is 0 to 400% is knee-compressed to 80% to 100%, so that a SDR image in which a dynamic range of luminance is 0 to 100% is generated and is then encoded.

Overview of Decoding in the First Mode

[00134] Figure 4 is a diagram illustrating a decoding overview in the first embodiment of a decoding device to which the present description is applied.

[00135] As illustrated in Figure 4, in the first embodiment, SDR image encoded data in which a dynamic range of luminance is 0 to 100%, generated as described in Figure 3, is decoded. In a case where a video unit is an SDR display, the SDR image that is obtained as a result of decoding is input and displayed on the display unit unchanged. On the other hand, in a case where the display unit is an HDR display, the SDR image obtained as a result of decoding is scaled to an HDR image, and is input and displayed on the display unit.

[00136] Specifically, as illustrated in Figure 5, 80% to 100% of the SDR image in which a dynamic range of luminance is knee-decompressed 0 to 100% to 80% to 400%, and thus an HDR image in which a dynamic range of luminance is 0 to 400% is generated. Also, the generated HDR image is displayed.

[00137] Furthermore, at this time, in order to generate a desired HDR image, information regarding the conversion of an SDR image into the desired HDR image, such as a gamma (80% to 100% in the example of Figure 5) of luminance of an SDR image that is knee-decompressed, and a range (80% to 400% in the example of Figure 5) of luminance of an HDR image corresponding to the gamma, is required. Therefore, in the first embodiment, conversion information relating to the conversion of an SDR image into an HDR image is transmitted from the encoding device to the decoding device, and thus a desired HDR image can be generated from a decoded SDR image. on the decoding device.

Configuration Example of the First Coding Device Mode

[00138] Figure 6 is a block diagram illustrating a configuration example of the first embodiment of an encoding device to which the present description is applied.

[00139] An encoding device 10 of Figure 6 includes a setting unit 11, a encoding unit 12, a transmission unit 13 and a conversion unit 14, and encodes an SDR image that is converted from an HDR image in a method conforming to the HEVC method.

[00140] Specifically, the establishment unit 11 of the encoding device 10 establishes a sequence parameter set (SPS), a frame parameter set (PPS), VUI, and the like. Furthermore, the establishment unit 11 sets Supplementary Enhancement Information (SEI) knee_function_info including conversion information in response to a command from a user (producer). Setting unit 11 provides sets of parameters including SPS, PPS, VUI, knee_function_info SEI, and the like set to coding unit 12.

[00141] The coding unit 12 encodes the SDR image provided by the conversion unit 14 in the HEVC method. The coding unit 12 generates a coded stream of coded data that is obtained as a result of the coding and the parameter sets that are provided by the setting unit 11, and transmits the generated coded stream to the transmission unit 13.

[00142] The transmission unit 13 transmits the encoded stream provided by the encoding unit 12 to a decoding device described later. Furthermore, the transmission unit 13 can transmit the encoded stream to a recording device which records the encoded stream onto a recording medium such as a BD. In this case, the encoded stream is transmitted to the decoding device via the recording medium.

[00143] The conversion unit 14 converts an HDR image input from an external device into an SDR image by knee compression, and provides the SDR image to the coding unit 12.

Example Syntax of knee_function_info SEI

[00144] Figure 7 is a diagram illustrating an example of knee_function_info SEI syntax, and Figure 8 is a diagram illustrating each piece of information set out in the knee_function_info SEI of Figure 7.

[00145] As illustrated in Figure 7, input knee position information (knee_point_of_input), output knee position information (knee_point_of_input), output luminance range information (output_white_level_range), output luminance information (output_white_level_range_luminance) , and similar are set in the knee_function_info SEI as conversion information.

[00146] The input knee position information is information indicating the minimum value (elbow) of luminance that is knee decompression of an SDR image that is an unconverted image. The input knee position information is a 'permillage' of an elbow when the maximum luminance value of an SDR image is set to 1000 permil.

[00147] The output knee position information is information indicating the luminance of an HDR image that is a converted image, corresponding to the minimum value (elbow) of luminance, which is a knee decompression objective of an SDR image which is an unconverted image. The output knee position information is a luminance 'permillage' corresponding to an elbow when the maximum luminance value of an HDR image is set to 1000 permil.

[00148] Output luminance gamma information is information indicating white luminance of an HDR image which is a converted image. In addition, the output luminance information is information indicating brightness (luminance) of the display unit, corresponding to white of the HDR image which is a converted image.

Example of Conversion Information

[00149] Figures 9 and 10 are diagrams illustrating examples of conversion information established in the knee_function_info SEI.

[00150] In the example in Figure 9, the user establishes an HDR image that is obtained as a result of knee decompressing 80% to 100% luminance of an SDR image to 80% to 400% is used as an HDR image desired. In this case, in the knee_function_info SEI, 800 as the input knee position information (knee_point_of_input), and 200 is set as the output knee position information (knee_point_of_output).

[00151] Therefore, a decoding device described later can knee decompress 80% to 100% luminance of an SDR image that is obtained as a result of decoding to 80% to 400% on the basis of the knee position information of input and output knee position information. As a result, the decoding device can convert the SDR image obtained as a result of decoding into a desired HDR image.

[00152] Furthermore, in the example in Figure 9, the output luminance range information (output_white_level_range) is 400, and the output luminance information (output_white_level_range_luminance) is 800 (candela per square meter).

[00153] In the example of Figure 10, the user sets an HDR image that is obtained as a result of knee decompressing 80% to 100% luminance of an SDR image to 100% to 400% as a desired HDR image. In this case, in the knee_function_info SEI, 800 is set as the input knee position information (knee_point_of_input), and 200 is set as the output knee position information (knee_point_of_output).

[00154] Therefore, the decoding device described later can knee decompress 80% to 100% luminance of an SDR image that is obtained as a result of decoding 100% to 400% on the basis of the knee position information of input and output knee position information. As a result, the decoding device can convert the SDR image obtained as a result of decoding into a desired HDR image.

[00155] Furthermore, in the example in Figure 10, the output luminance range information (output_white_level_range) is 400, and the output luminance information (output_white_level_range_luminace) is 800 (candela per square meter).

Description of the Process in the Encoding Device

[00156] Figure 11 is a flowchart illustrating a flow generation process performed by the coding device 10.

[00157] In step S10 of Figure 11, the conversion unit 14 of the coding device 10 converts an HDR image that is input from an external device, into an SDR image that is then provided to the coding unit 12.

[00158] In step S11, the establishment unit 11 establishes an SPS. In step S12, the setting unit 11 sets VUI. In step S13, the setting unit 11 establishes a PPS.

[00159] In step S14, the establishment unit 11 establishes knee_function_info SEI in response to an instruction or the like from a user. Setting unit 11 provides the sets of parameters including SPS, PPS, VUI, knee_function_info SEI, and the like set to coding unit 12.

[00160] In step S15, the coding unit 12 encodes the SDR image provided by the conversion unit 14 in the HEVC method. In step S16, the coding unit 12 generates a coded stream of coded data that is obtained as a result of coding and the parameter sets that are provided by the setting unit 11, and transmits the generated coded stream to the transmission unit 13.

[00161] In step S17, the transmission unit 13 transmits the coded stream provided by the coder unit 12 to the decoding device described later, and then ends the process.

[00162] As mentioned above, the encoding device 10 establishes and transmits knee_function_info SEI including conversion information, and thus the decoding device described later can convert an SDR image obtained as a result of decoding into a desired HDR image on the basis conversion information. Therefore, it can be said that the encoding device 10 can encode an SDR image so that a decoded SDR image can be converted into a desired HDR image during decoding.

[00163] Furthermore, since the conversion information is established, the encoding device 10 can generate an encoded stream of an image corresponding to an HDR display and an SDR display just by encoding an SDR image. Therefore, it is possible to additionally reduce an amount of data from an encoded stream than in a case of encoding both an HDR image and an SDR image.

First Mode Decoding Device Configuration Example

[00164] Figure 12 is a block diagram illustrating an example configuration of an embodiment of a decoding device that decodes an encoded stream transmitted from the encoding device 10 of Figure 6 and to which the present description is applied.

[00165] A decoding device 50 of Figure 12 includes a receiving unit 51, an extracting unit 52, a decoding unit 53, a converting unit 54, a display control unit 55 and a display unit 56.

[00166] The receiver unit 51 of the decoding device 50 receives the encoded stream transmitted from the encoding device 10 of Figure 6, and provides the encoded stream to the extraction unit 52.

[00167] The extraction unit 52 extracts the parameter sets and the encoded data from the SDR image from the encoded stream that is provided by the receiving unit 51. The extraction unit 52 provides the parameter sets and the encoded data to the unit of decoding unit 53. Furthermore, extraction unit 52 provides the knee_function_info SEI among the parameter sets, to conversion unit 54.

[00168] The decoding unit 53 decodes the SDR image encoded data provided by the extracting unit 52 in the HEVC method. At this time, the decoding unit 53 also refers to the parameter sets provided from the extracting unit 52, as required. The decoding unit 53 provides the SDR image that is obtained as a result of decoding to the conversion unit 54.

[00169] The conversion unit 54 converts the SDR image provided by the decoding unit 53 into an HDR image by knee decompression on the basis of the conversion information included in the knee_function_info SEI provided by the extraction unit 52, and provides the image of HDR for display control unit 55.

[00170] The display control unit 55 displays the HDR image provided by the conversion unit 54 on the display unit 56. The display unit 56 is an HDR display.

Description of the Decoding Device Process

[00171] Figure 13 is a flowchart illustrating an image generation process performed by the decoding device 50 of Figure 12.

[00172] In step S51 of Figure 13, the receiver unit 51 of the decoding device 50 receives the coded stream transmitted from the coder device 10 of Figure 6, and provides the coded stream to the extraction unit 52.

[00173] In step S52, the extraction unit 52 extracts the parameter sets and the encoded data from the SDR image from the encoded stream that is provided by the receiving unit 51. The extraction unit 52 provides the parameter sets and the data encoded from the SDR image to the decoding unit 53. Furthermore, the extraction unit 52 provides the knee_function_info SEI among the sets of parameters to the conversion unit 54.

[00174] In the step S53, the decoding unit 53 decodes the SDR image encoded data provided by the extracting unit 52 in the HEVC method. At this time, the decoding unit 53 also refers to the parameter sets provided from the extracting unit 52, as required. The decoding unit 53 provides the SDR image that is obtained as a result of decoding to the conversion unit 54.

[00175] In step S54, the conversion unit 54 acquires the conversion information from the knee_function_info SEI that is provided by the extraction unit 52.

[00176] In the step S55, the conversion unit 54 converts the SDR image provided by the decoding unit 53 into an HDR image on the basis of the conversion information, and provides the HDR image to the display control unit 55.

[00177] At step S56, the display control unit 55 displays the HDR image provided by the conversion unit 54 on the display unit 56, and ends the process.

[00178] As mentioned above, the decoding device 50 converts the SDR image obtained as a result of decoding into the HDR image on the basis of the conversion information, and thus can convert the SDR image obtained as a result of decoding into a HDR image. Desired HDR.

Another Syntax Example of knee_function_info SEI

[00179] Figure 14 is a diagram illustrating another syntax example of the knee_function_info SEI, and Figure 15 is a diagram illustrating each piece of information set established in the knee_function_info SEI of Figure 14.

[00180] The knee_function_info SEI of Figure 14 is the same as the knee_function_info SEI of Figure 7, except that the luminance range information (white_level_range) and luminance information (white_level_range_luminance) are set instead of the output luminance range information (output_white_level_range ) and output luminance information (output_white_level_range_luminance).

[00181] Luminance gamma information is output luminance gamma information when input knee position information (knee_point_of_input) is equal to or more than output knee position information (knee_point_of_output), that is, when Knee decompression is performed on a decoding side in the same manner as in the first embodiment.

[00182] On the other hand, when the input knee position information is less than the output knee position information, that is, when knee compression is performed on the decoding side, the luminance gamma information is information indicating white luminance of an unconverted image (for example, an HDR image).

[00183] Similarly, luminance information (white_level_range_luminance) is output luminance information when input knee position information is equal to or more than output knee position information in the same way as in the first embodiment, and is information indicating white luminance (value) of an unconverted image (eg an HDR image) when the input knee position information is less than the output knee position information.

[00184] Furthermore, in the first embodiment, only an SDR image is encoded in the coding device 10, but only an HDR image converted from the SDR image can be encoded. In this case, information regarding the conversion of the SDR image into the HDR image is set in SEI and is transmitted to the decoding device 50. Specifically, the knee_function_info SEI illustrated in Figure 7 or Figure 15 in which an unconverted image is set as an HDR image, and a converted image is established as an SDR image is transmitted to the decoding device 50. Furthermore, the decoding device 50 converts an HDR image into an original SDR image with high precision on the basis of knee_function_info SEI.

[00185] Furthermore, in the first embodiment, the display unit 56 is an HDR display, but the display unit 56 may be an SDR display. In this case, the conversion unit 54 provides an SDR image to the display control unit 55 without conversion to an HDR image. Therefore, the SDR image is displayed on the display unit 56.

[00186] In addition, a desired image may be an HDR image that is input to encoding device 10.

[00187] Furthermore, in the first embodiment, the encoding device 10 converts an HDR image that is input from an external device into an SDR image that is then encoded, but it can encode an SDR image that is input from the external device no conversion.

Second Modality Configuration Example of the Second Coding Device Mode

[00188] Figure 16 is a block diagram illustrating an example configuration of a second embodiment of an encoding device to which the present description is applied.

[00189] Among constituent elements illustrated in Figure 16, the same constituent elements as the constituent elements of Figure 6 are given the same reference numerals. Repeated description will be omitted as appropriate.

[00190] A configuration of a coding device 70 of Figure 16 is different from the configuration of the coding device 10 of Figure 6 in that a setting unit 71, a coding unit 72 and a conversion unit 73 are provided instead of the establishment unit 11, the encoding unit 12 and the conversion unit 14. The encoding device 70 encodes an HDR image that is input from an external device, or encodes an SDR image that is converted from an HDR image, in a method conforming to the HEVC method.

[00191] Specifically, the setting unit 71 of the encoding device 70 sets up an SPS, a PPS, VUI, and the like. Furthermore, the setting unit 71 sets SEI as knee_function_info SEI including DR conversion information in response to a command from a user (producer). DR conversion information is information relating to the conversion of a luminance dynamic range of an image that is a coding objective into a different dynamic range. Setting unit 71 provides the sets of parameters including the SPS, PPS, VUI, knee_function_info SEI set, and similar to coding unit 72.

[00192] The encoding unit 72 sets an HDR image or an SDR image provided by the conversion unit 73 as an encoding target image, and encodes the encoding target image in the HEVC method. The coding unit 72 generates a coded stream of coded data that is obtained as a result of the coding and the parameter sets that are provided by the setting unit 71, and transmits the generated coded stream to the transmission unit 13.

[00193] The conversion unit 73 knee-compresses the luminance of an HDR image that is input from an external device in order to generate an SDR image that is then provided to the coding unit 72, or provides an HDR image that it is input from external device to coding unit 72 without compression.

First Example of the Syntax of knee_function_info SEI

[00194] Figure 17 is a diagram illustrating a first syntax example of the knee_function_info SEI established by the establishment unit 71 of Figure 16, and Figure 18 is a diagram illustrating each piece of information established in the knee_function_info SEI of Figure 17.

[00195] As illustrated in Figure 17, a knee conversion ID (knee_function_id) and a knee conversion cancel flag (knee_function_cancel_flag) are set in the knee_function_info SEI.

[00196] The knee conversion ID is a unique ID for the purpose of knee conversion, which is knee compression or knee decompression as illustrated in Figure 18. In addition, the knee conversion cancel flag is a flag illustrating whether or not persistence of the previous knee_function_info SEI is canceled. The knee conversion cancel flag is set to 1 when indicating that persistence of the previous knee_function_info SEI is canceled, and it is set to 0 when persistence is not canceled.

[00197] If the knee conversion cancel flag is 0, as illustrated in Figure 17, a single piece of pre-conversion position information (input_knee_point), a single piece of post-conversion position information (output_knee_point) , HDR luminance range information (d_range), and display luminance information (d_range_disp_luminance) are set in knee_function_info SEI as DR conversion information.

[00198] The pre-conversion position information is information indicating an elbow of a coding target image that is a non-converted image in conversion corresponding to the DR conversion information, and is a 'permillage' of an elbow when the value maximum luminance of the coding target image is set at 1000 permil. The elbow is luminance (which is a value obtained by normalizing linear RGB values in the range 0.0 to 1.1) different from 0, which is a starting point of a luminance range that is converted to knee at the same ratio of conversion as that of a dynamic range of luminance of the coding target image.

[00199] Post-conversion position information is information indicating a starting point of a luminance range corresponding to a knee-converted luminance range that has an elbow as a starting point in an image after it is converted ( then called a converted image) in conversion corresponding to the DR conversion information. Specifically, the post-conversion position information is a luminance permillage of a converted image corresponding to an elbow when the maximum luminance value of the converted image is set to 1000 permil.

[00200] HDR luminance range information is information indicating a 'permillage' of the maximum luminance value of an HDR image that is a coding target image or a converted image. Furthermore, display luminance information is information indicating an expected brightness (luminance) value of the display unit corresponding to the maximum luminance value of an HDR image. First Example of DR Conversion Information

[00201] Figures 19 and 20 are diagrams illustrating examples of the DR conversion information established in the knee_function_info SEI of Figure 17.

[00202] In the example of Figure 19, an encoding target image is an SDR image, and a user establishes an HDR image that is obtained as a result of knee decompressing 80% to 100% luminance of the SDR image at 80 % to 400%, as a desired converted image. In this case, in the knee_function_info SEI, 800 is set as the pre-conversion position information (input_knee_point), and 200 is set as the post-conversion position information (output_knee_point).

[00203] Furthermore, in the example of Figure 19, the HDR luminance range information (d_range) is 4000, and the display luminance range information (d_range_disp_luminance) is 800 (candela per square meter).

[00204] As in the case of Figure 19, in a case where an encoding target image is an SDR image, and a converted image is an HDR image, an input_knee_point_PER (%) and output_knee_point_PER (%) luminance elbow of a converted image corresponding to the elbow are defined by the following Equation (1).

[00205] Therefore, a decoding device described later recognizes that the elbow input_knee_point_PER and the luminance output_knee_point_PER are 80% according to Equation (1). Furthermore, the decoding device described later recognizes that knee conversion corresponding to the DR conversion information is knee decompression since the pre-conversion position information is equal to or more than the post-conversion position information. . Additionally, the decoding device described later recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information.

[00206] As mentioned above, the decoding device described later knee-decompresses 80% to 100% luminance of the SDR image that is obtained as a result of decoding to 80% to 400%. Therefore, the decoding device can convert the SDR image obtained as a result of decoding into a desired HDR image.

[00207] In the example of Figure 20, a coding target image is an HDR image, and the user establishes an SDR image that is obtained as a result of knee-compressing 80% to 400% luminance of the HDR image at 80 % to 100%, as a desired converted image. In this case, in the knee_function_info SEI, 200 is set as the pre-conversion position information (input_knee_point), and 800 is set as the post-conversion position information (output_knee_point).

[00208] Furthermore, in the example of Figure 20, the HDR luminance range information (d_range) is 4000, and the display luminance range information (d_range_disp_luminance) is 800 (candela per square meter).

[00209] As in the case of Figure 20, in a case where an encoding target image is an HDR image, and a converted image is an SDR image, an input_knee_point_PER (%) and output_knee_point_PER (%) luminance elbow of a converted image corresponding to the elbow are defined by the following Equation (2).

[00210] Therefore, the decoding device described later recognizes that the elbow input_knee_point_PER and output_knee_point_PER of luminance are 80% according to Equation (2). Furthermore, the decoding device described later recognizes that knee conversion corresponding to DR conversion information is knee compression since the pre-conversion position information is less than the post-conversion position information. Additionally, the decoding device described later recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information.

[00211] As mentioned above, the decoding device described later knee-compresses 80% to 400% luminance of the SDR image that is obtained as a result of decoding, to 80% to 100%. Therefore, the decoding device can convert the HDR image obtained as a result of decoding into a desired SDR image. Description of the Encoding Device Process

[00212] Figure 21 is a flowchart illustrating a flow generation process performed by the coding device 70 of Figure 16.

[00213] At step S71 of Figure 21, the conversion unit 73 of the encoding device 70 determines whether or not, for example, an encoding target image is an SDR image in response to an instruction or the like from the user. If a coding target image is determined to be an SDR image in step S71, the process proceeds to step S72.

[00214] In step S72, the conversion unit 73 converts an HDR image that is input from an external device into an SDR image by luminance knee compression of the HDR image, and provides the SDR image to the conversion unit coding 72.

[00215] On the other hand, if it is determined that an encoding target image is not an SDR image in step S71, that is, an encoding target image is an HDR image, the conversion unit 73 provides an HDR image which is input from an external device to the coding unit 72 without change, and the process proceeds to step S73.

[00216] In step S73, the establishment unit 71 establishes an SPS. In step S74, the setting unit 71 sets VUI. In step S75, the setting unit 71 establishes a PPS.

[00217] In step S76, the setting unit 71 sets knee_function_info SEI in response to an instruction or the like from a user. Setting unit 71 provides the sets of parameters including SPS, PPS, VUI, knee_function_info SEI, and the like set to coding unit 72.

[00218] In the step S77, the coding unit 72 encodes an SDR image or an HDR image provided by the conversion unit 73 as a coding target image in the HEVC method. In step S78, the coding unit 72 generates a coded stream of coded data which is obtained as a result of coding and the parameter sets which are provided by the setting unit 71, and transmits the generated coded stream to the transmission unit 13.

[00219] In the step S79, the transmission unit 13 transmits the encoded stream provided from the encoding unit 72 to the decoding device described later, and then ends the process.

[00220] As mentioned above, the encoding device 70 establishes and transmits knee_function_info SEI including DR conversion information, and thus the decoding device described later can convert an encoding target image obtained as a result of decoding into a desired converted image on the basis of DR conversion information. Therefore, it can be said that the encoding device 70 can encode an image such that a decoded image can be converted into a desired converted image during decoding.

[00221] Furthermore, since the DR conversion information is established, the encoding device 70 can generate an encoded stream of an image corresponding to an HDR display and an SDR display just by encoding an SDR image or an image of HDR. Therefore, it is possible to additionally reduce an amount of data from an encoded stream than in a case of encoding both an HDR image and an SDR image. Second Decoding Device Mode Configuration Example

[00222] Figure 22 is a block diagram illustrating a configuration example of a second embodiment of a decoding device that decodes an encoded stream transmitted from the encoding device 70 of Figure 16 and to which the present description is applied.

[00223] Among the constituent elements illustrated in Figure 22, the same constituent elements as the constituent elements of Figure 12 are given the same reference numerals. Repeated description will be omitted as appropriate.

[00224] A configuration of a decoding device 90 of Figure 22 is different from the configuration of the decoding device 50 of Figure 12 since an extraction unit 91, a decoding unit 92, a conversion unit 93, a control unit A display unit 94 and a display unit 95 are provided in place of the extraction unit 52, the decoding unit 53, the conversion unit 54, the display control unit 55 and the display unit 56. The decoding device 90 converts a decoded image into a converted image according to the display unit type 95, and displays the converted image on the display unit 95.

[00225] Specifically, the extracting unit 91 of the decoding device 90 extracts parameter sets and encoded data from an encoded stream that is provided by the receiving unit 51. The extracting unit 91 provides the parameter sets and encoded data for the decoding unit 92. Furthermore, the extracting unit 91 provides knee_function_info SEI among the sets of parameters to the converting unit 93.

[00226] The decoding unit 92 decodes the encoded data provided from the extracting unit 91 in the HEVC method. At this time, the decoding unit 92 also refers to the parameter sets provided from the extracting unit 91, as required. Decoding unit 92 provides a decoded image to conversion unit 93.

[00227] In a case where a dynamic range of luminance corresponding to the display unit 95 is a dynamic range of luminance of the decoded image, the conversion unit 93 provides the decoded image, which is provided by the decoding unit 92, to the unit of display control 94 without change. On the other hand, in a case where a luminance dynamic range corresponding to the display unit 95 is not a luminance dynamic range of the decoded image, the conversion unit 93 converts the decoded image into a converted image by knee conversion on the basis of DR conversion information included in the knee_function_info SEI provided by the extraction unit 91. Furthermore, the conversion unit 93 provides the converted image to the display control unit 94 as a display image.

[00228] Specifically, in a case where the display unit 95 is an HDR display, and the decoded picture is an HDR picture, or in a case where the display unit 95 is an SDR display, and the decoded picture is an SDR image, the conversion unit 93 provides the decoded image to the display control unit 94 unchanged. On the other hand, in a case where the display unit 95 is an SDR display, and the decoded picture is an HDR picture, or in a case where the display unit 95 is an HDR display, and the decoded picture is an SDR image, the conversion unit 93 performs knee conversion on the decoded image on the basis of the DR conversion information to generate a converted image. Furthermore, the conversion unit 93 provides the converted image to the display control unit 94 as a display image.

[00229] The display control unit 94 displays the display image provided by the conversion unit 93 on the display unit 95. Therefore, in a case where the display unit 95 is an HDR display, an HDR image is displayed on the display unit 95, and in a case where the display unit 95 is an SDR display, an SDR image is displayed on the display unit 95. The display unit 95 is an HDR display or an SDR display , and displays a display image provided by the display control unit 94.

Description of the Process in the Decoding Device

[00230] Figure 23 is a flowchart illustrating an image generation process performed by the decoding device 90 of Figure 22.

[00231] In step S91 of Fig. 23, the receiver unit 51 of the decoding device 90 receives an encoded stream transmitted from the encoding device 70 of Fig. 16, and provides the encoded stream to the extraction unit 91.

[00232] At step S92, the extracting unit 91 extracts parameter sets and encoded data from the encoded stream that is provided by the receiving unit 51. The extracting unit 91 provides the parameter sets and encoded data to the decoding unit 92. Furthermore, the extraction unit 91 provides knee_function_info SEI among the parameter sets, to the conversion unit 93.

[00233] In the step S93, the decoding unit 92 decodes the encoded data provided from the extracting unit 91 in the HEVC method. At this time, the decoding unit 92 also refers to the parameter sets provided from the extracting unit 91, as required. Decoding unit 92 provides a decoded image to conversion unit 93.

[00234] In step S94, the conversion unit 93 acquires the DR conversion information from the knee_function_info SEI that is provided by the extraction unit 91.

[00235] At step S95, the conversion unit 93 determines whether or not a luminance dynamic range corresponding to the display unit 95 is a luminance dynamic range of the decoded image. If it is determined that a luminance dynamic range corresponding to the display unit 95 is not a luminance dynamic range of the decoded image, the process proceeds to step S96.

[00236] In the step S96, the conversion unit 93 converts the decoded image provided by the decoding unit 92 into a converted image on the basis of the DR conversion information, and provides the converted image to the display control unit 94 as a display image. Further, the process proceeds to step S97.

[00237] On the other hand, it is determined at step S95 that a luminance dynamic range corresponding to the display unit 95 is a luminance dynamic range of the decoded image, the conversion unit 93 provides the decoded image which is provided by the decoding unit 92, to the display control unit 94 as an unchanged display image. Further, the process proceeds to step S97.

[00238] In step S97, the display control unit 94 displays the display image provided by the conversion unit 93 on the display unit 95, and ends the process.

[00239] As mentioned above, the decoding device 90 converts the decoded image into the converted image on the basis of the DR conversion information, and thus can convert a decoded image to a desired converted image.

[00240] Furthermore, in the second embodiment, one of an SDR image and an HDR image is a coding target image, and the other is a converted image, but an SDR image can be replaced with a desensitized development image of an HDR image in which an expected brightness value of the display unit corresponding to the maximum luminance value is greater than that of the SDR image. Second Example of DR Conversion Information

[00241] Figures 24 and 25 are diagrams illustrating examples of DR conversion information set in knee_function_info SEI in a case where one of a desensitized development image and an HDR image is a coding target image and the other is a coding target image. converted.

[00242] Furthermore, in the examples of Figures 24 and 25, the desensitized development image is an image in which a dynamic range of luminance is 0 to 200%, obtained by performing desensitized development of 1 EV (description value) on an image of HDR. Additionally, an expected brightness value of the display unit corresponding to the maximum luminance value of the desensitized development image is 400 (candela per square meter) higher than 200 (candela per square meter) which is an expected brightness value corresponding to the maximum luminance value in an SDR image.

[00243] Information indicating that a coding target image or a converted image is an image obtained by performing desensitized development on an HDR image, and a dynamic range of luminance of the desensitized development image are set in tone_mapping_info_SEI by establishment unit 71.

[00244] In the example of Figure 24, a coding target image is a desensitized development image, and the user sets an HDR image that is obtained as a result of knee decompressing 160% to 200% luminance of the desensitized development image to 160% to 400%, as a desired converted image. In this case, in the knee_function_info SEI, 800 is set as the pre-conversion position information (input_knee_point), and 400 is set as the post-conversion position information (output_knee_point).

[00245] Furthermore, in the example in Figure 24, the HDR luminance range information (d_range) is 4000, and the display luminance range (d_range_disp_luminance) is 800 (candela per square meter).

[00246] As in the case of Figure 24, in a case where an encoding target image is a desensitized development image, and a converted image is an HDR image, an elbow input_knee_point_PER (%) and luminance output_knee_point_PER (%) of a converted image corresponding to the elbow are defined by Equation (1) above.

[00247] Therefore, the decoding device 90 recognizes that the elbow input_knee_point_PER and the luminance output_knee_point_PER are 160% according to Equation (1). Furthermore, the decoding device 90 recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information. Additionally, the decoding device 90 recognizes that a dynamic range of luminance of the encoding target image is 0 to 200% of the tone_mapping_info_SEI. Furthermore, in a case where the display unit 95 is an HDR display, 160% to 200% luminance of a desensitized development image that is obtained as a result of decoding is knee-decompressed to 160% to 400% so to be displayed as a display image.

[00248] On the other hand, in a case where the display unit 95 is an SDR display, the decoding device 90 displays a desensitized development picture as an unchanged display picture. At this time, an expected brightness value of the display unit corresponding to the maximum luminance value of the desensitized development image is greater than that of an SDR image, and thus the brightness of the display image is insufficient.

[00249] However, recently, an SDR display (hereinafter called a high luminance SDR display) of which the brightness corresponding to the maximum luminance value is relatively high 300 (candela per square meter) or similar has been developed. In a case where the display unit 95 is a high luminance SDR display, the brightness of a display image can be maintained sufficiently even if a desensitized development image is displayed as the display image without change. Furthermore, since a knee compression ratio during generation of a coding target image is lower than in a case where a coding target image is an SDR image, the quality of a display image can be enhanced.

[00250] In the example of Figure 25, a coding target image is an HDR image, and the user establishes a desensitized development image that is obtained as a result of knee-compressing 160% to 400% luminance of the HDR image to 160% to 200%, as a desired converted image. In this case, in the knee_function_info SEI, 400 is set as the pre-conversion position information (input_knee_point), and 800 is set as the post-conversion position information (output_knee_point).

[00251] Furthermore, in the example in Figure 25, the HDR luminance range information (d_range) is 4000, and the display luminance range (d_range_disp_luminance) is 800 (candela per square meter).

[00252] As in the case of Figure 25, in a case where an encoding target image is an HDR image, and a converted image is a desensitized development image, an elbow input_knee_point_PER (%) and luminance output_knee_point_PER (%) of a converted image corresponding to the elbow are defined by Equation (2) above.

[00253] Therefore, the decoding device 90 recognizes that the elbow input_knee_point_PER and the luminance output_knee_point_PER are 160% according to Equation (2). Furthermore, the decoding device 90 recognizes that the maximum luminance value of the encoding target image is 400% of the HDR luminance gamma information. Additionally, the decoding device 90 recognizes that a dynamic range of luminance of the converted image is 0 to 200% of the tone_mapping_info_SEI.

[00254] Furthermore, in a case where the display unit 95 is an SDR display, the decoding device 90 knee-compresses 160% to 400% luminance of an HDR image that is obtained as a result of decoding at 160 % to 200% to display a compressed result as a display image. In this case, as described above, the display image brightness is insufficient. However, in a case where the display unit 95 is a high luminance SDR display, the brightness of a display image can be maintained sufficiently as described above. Also, the quality of a display image can be improved.

[00255] On the other hand, in a case where the display unit 95 is an HDR display, the decoding device 90 displays an HDR image that is obtained as a result of decoding as an unchanged display image.

[00256] Furthermore, the DR conversion information of Fig. 17 can be included in SEI such as tone_mapping_info_SEI other than knee_function_info SEI.

First Example of tone_mapping_info_SEI Syntax

[00257] Figure 26 is a diagram illustrating an example tone_mapping_info_SEI syntax in a case where the DR conversion information from Figure 17 is included in the tone_mapping_info_SEI.

[00258] The tone_mapping_info_SEI is SEI related to luminance conversion. As illustrated in Figure 26, in a case where the DR conversion information from Figure 17 is included in tone_mapping_info_SEI, tone_map_model_id indicating a luminance conversion model is set to, for example, 5. Furthermore, in tone_mapping_info_SEI, position information Pre-conversion information (input_knee_point), post-conversion position information (output_knee_point), HDR luminance range information (d_range), and display luminance information (d_range_disp_luminance) are set in tone_mapping_info_SEI as DR conversion information.

[00259] In addition, HDR luminance range information (d_range) and display luminance information (d_range_disp_luminance) are included in tone_mapping_info_SEI when tone_map_model_id is 4. Therefore, as illustrated in Figure 27, the luminance range information of HDR (d_range) and display luminance information (d_range_disp_luminance) may not be included in tone_mapping_info_SEI. Additionally, only one of the HDR luminance range information (d_range) and the display luminance information (d_range_disp_luminance) can be included.

Second Syntax Example of knee_function_info SEI

[00260] Figure 28 is a diagram illustrating a second syntax example of the knee_function_info SEI established by the establishment unit 71 of Figure 16, and Figure 29 is a diagram illustrating each piece of information established in the knee_function_info SEI of Figure 28.

[00261] A plurality of elbows are set in the knee_function_info SEI of Figure 28. Specifically, in the same way as in the case of Figure 17, a knee conversion ID (knee_function_id) and a knee conversion cancellation flag (knee_function_cancel_flag) are established in the knee_function_info SEI of Figure 28.

[00262] Furthermore, if the knee conversion cancel flag is 0, as illustrated in Figure 28, the DR conversion information is set in the knee_function_info SEI. DR conversion information is the same as in the case of Figure 17, except that a compression flag (compression_flag) and elbow number (num_knee_point_minus1) are included, and pre-conversion position information (input_knee_point) and position information of post-conversion (output_knee_point) are established for each elbow. Description of the same part as in the case of Figure 17 is repeated and so will be omitted as appropriate.

[00263] As illustrated in Figure 29, the compression flag is a flag indicating whether or not the knee conversion is knee compression. In other words, in a case where the number of elbows is one, when the pre-conversion position information (input_knee_point) is equal to or more than the post-conversion position information (output_knee_point), it can be determined that the knee conversion is knee decompression, and when the pre-conversion position information (input_knee_point) is less than the post-conversion position information (output_knee_point), it can be determined that the knee conversion is knee compression.

[00264] However, in a case where there are multiple elbows, it cannot be precisely determined whether the knee conversion is knee decompression or knee compression using the magnitude correlation between the pre-conversion position information and the position information of post-conversion, and thus the compression flag is set. Furthermore, even in a case where the number of elbows is one, the compression flag can be set. The compression flag is set to 1 when knee conversion is knee compression, and is set to 0 when knee conversion is knee decompression.

[00265] The number of elbows is a value obtained by subtracting 1 from the number of elbows. Furthermore, an order i (where i is an integer of 0 or more) in which pre-conversion position information and post-conversion position information of elbows are established is an order in which the pre-conversion position information conversion is reduced. Third Example of DR Conversion Information

[00266] Figures 30 and 31 are diagrams illustrating examples of DR conversion information established in the knee_function_info SEI of Figure 28.

[00267] In the example of Fig. 30, an encoding target image is an SDR image. In addition, the user sets an HDR image that is obtained as a result of respectively converting 0 to 60%, 60% to 80%, 80% to 90%, and 90% to 100% of an SDR image into 0 to 40 %, 40% to 100%, 100% to 180%, and 180% to 400%, as a desired converted image.

[00268] In this case, in knee_function_info SEI, 600 is set as pre-conversion position information (input_knee_point [0]) of the 0-th elbow, and 100 is set as post-conversion position information (output_knee_point [0] ) from that. 800 is set as pre-conversion position information (input_knee_point[1]) of the first elbow, and 250 is set as post-conversion position information (output_knee_point[1]) thereof. 900 is set as pre-conversion position information (input_knee_point[2]) of the second elbow, and 450 is set as post-conversion position information (output_knee_point[2]) thereof.

[00269] Furthermore, in the example in Figure 30, the HDR luminance range information (d_range) is 4000, the display luminance range (d_range_disp_luminance) is 800 (candela per square meter), and the compression signal ( compression_flag) is 0.

[00270] As described above, in a case where an encoding target image is an SDR image, and a converted image is an HDR image, an input_knee_point_PER elbow (%) and output_knee_point_PER luminance (%) of a converted image corresponding to the elbow are defined by Equation (1) above.

[00271] Therefore, the decoding device 90 recognizes that the 0-th to second input_knee_point_PER elbows are respectively 60%, 80%, and 90% according to Equation (1). Furthermore, the decoding device 90 recognizes that the 0th and second luminances output_knee_point_PER are respectively 40%, 100%, and 180%. Additionally, the decoding device 90 recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information.

[00272] In addition, the decoding device 90 respectively converts into knee 0 to 60%, 60% to 80%, 80% to 90%, and 90% to 100% of an SDR image that is obtained as a result of decoding in 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400%, according to a straight line conversion in which the elbows are connected to each other in a set order. Therefore, the decoding device 90 can convert the SDR image that is obtained as a result of decoding into a desired HDR image.

[00273] In the example of Figure 31, an encoding target image is an HDR image. In addition, the user establishes an SDR image that is obtained as a result of converting respectively 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400% of the luminance of an HDR image to 0 to 60%, 60% to 80%, 80% to 90%, and 90% to 100%, as a desired converted image.

[00274] In this case, in knee_function_info SEI, 100 is set as pre-conversion position information (input_knee_point [0]) of the 0-th elbow, and 600 is set as post-conversion position information (output_knee_point [0] ). 250 is set as pre-conversion position information (input_knee_point[1]) of the first elbow, and 800 is set as post-conversion position information (output_knee_point[1]). 450 is set as pre-conversion position information (input_knee_point[2]) of the second elbow, and 900 is set as post-conversion position information (output_knee_point[2]).

[00275] Furthermore, in the example in Figure 31, the HDR luminance range information (d_range) is 4000, the display luminance range (d_range_disp_luminance) is 800 (candela per square meter), and the compression signal ( compression_flag) is 1.

[00276] As described above, in a case where an encoding target image is an HDR image, and a converted image is an SDR image, an input_knee_point_PER elbow (%) and output_knee_point_PER luminance (%) of a converted image corresponding to the elbow are defined by Equation (2) above.

[00277] Therefore, the decoding device 90 recognizes that the 0-th to second input_knee_point_PER elbows are respectively 40%, 100%, and 180% according to Equation (2). Furthermore, the 0th and 2nd output_knee_point_PER luminances (%) are respectively 60%, 80%, and 90%. Furthermore, the decoding device 90 recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information.

[00278] Additionally, the decoding device 90 knee converts 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400% of an HDR image that is obtained as a result of decoding at 0 to 60%, 60% to 80%, 80% to 90%, and 90% to 100% connecting the elbows to each other in a set order. Therefore, the decoding device 90 can convert the HDR image that is obtained as a result of decoding into a desired SDR image.

[00279] As mentioned above, in a case where a plurality of elbows is established, a compression ratio can be established more finely than in a case where a single elbow is established. Therefore, it is possible to perform knee conversion with higher accuracy.

[00280] Furthermore, the DR conversion information of Fig. 28 can be included in SEI such as tone_mapping_info_SEI other than knee_function_info SEI. Second Example of tone_mapping_info_SEI Syntax

[00281] Figure 32 is a diagram illustrating an example of tone_mapping_info_SEI syntax in a case where the DR conversion information from Figure 28 is included in tone_mapping_info_SEI.

[00282] As illustrated in Figure 32, in a case where the DR conversion information from Figure 28 is included in the tone_mapping_info_SEI, the tone_map_model_id is set to, for example, 5. Furthermore, in the tone_mapping_info_SEI, the compression flag (compression_flag (mapping_flag)), HDR luminance range information (d_range), display luminance information (d_range_disp_luminance), an elbow number (num_knee_point_minus1), and preconversion position information (input_knee_point) and post position information -conversion (output_knee_point) of each elbow are set in tone_mapping_info_SEI as DR conversion information.

[00283] Also, just as in the tone_mapping_info_SEI of Figure 27, the HDR luminance range information (d_range) and the display luminance information (d_range_disp_luminance) may not be included in the tone_mapping_info_SEI of Figure 32. Additionally, only one of HDR luminance range information (d_range) and display luminance information (d_range_disp_luminance) may be included.

[00284] Furthermore, the elbow number (num_knee_point_minus1) can be any one of 0, 1, and 2 as illustrated in Figures 33 to 35. In other words, the elbow number (num_knee_point_minus1) can be limited to 2 or less . In this case, as illustrated in Figures 33 to 35, the number of bits of the elbow number (num_knee_point_minus1) included in the knee_function_info SEI or in the tone_mapping_info_SEI is fixed to 2 bits (u(2)).

[00285] As mentioned above, the maximum value of the elbow number (num_knee_point_minus1) is determined, and thus an amount of DR conversion information can be reduced. Therefore, DR conversion information can be transmitted with a small packet as in High Definition Multimedia Interface (HDMI) AVI InfoFrame. Third Syntax Example of knee_function_info SEI

[00286] Figure 36 is a diagram illustrating a third syntax example of the knee_function_info SEI established by the establishment unit 71 of Figure 16, and Figure 37 is a diagram illustrating each piece of information established in the knee_function_info SEI of Figure 36.

[00287] A plurality of elbows and an elbow (hereinafter called a representative elbow) that is used representatively are set out in the knee_function_info SEI of Figure 36.

[00288] Specifically, in the same way as in the case of Figure 17, a knee conversion ID (knee_function_id) and a knee conversion cancellation flag (knee_function_cancel_flag) are set in the knee_function_info SEI of Figure 36.

[00289] Furthermore, if the knee conversion cancel flag is 0, as illustrated in Figure 36, the DR conversion information is set in the knee_function_info SEI. The DR conversion information is the same as in the case of Figure 28, except that representative pre-conversion position information (representative_input_knee_point) and representative post-conversion position information (representative_output_knee_point) are included. Description of the same part as in the case of Figure 28 is repeated and so will be omitted as appropriate.

[00290] As illustrated in Figure 37, the representative pre-conversion position information is information indicating a representative elbow of a coding target image which is an unconverted image in conversion corresponding to the DR conversion information, and is a ' permillage' of the representative elbow when the maximum luminance value of the coding target image is set to 1000 permil.

[00291] Representative pre-conversion position information is information indicating luminance corresponding to a representative elbow of a converted image in conversion corresponding to DR conversion information, and is a luminance permillage corresponding to an elbow when the value maximum luminance of the converted image is set to 1000 permil.

[00292] Furthermore, the representative elbow may be one of elbows corresponding to a plurality of pieces of pre-conversion position information included in the DR conversion information, and it may be an elbow that is completely different from the elbow.

Fourth Example of DR Conversion Information

[00293] Figure 38 is a diagram illustrating an example of DR conversion information established in the knee_function_info SEI of Figure 36.

[00294] In the example of Fig. 38, an encoding target image is an SDR image. In addition, the user sets an HDR image that is obtained as a result of respectively converting 0 to 60%, 60% to 80%, 80% to 90%, and 90% to 100% of an SDR image into 0 to 40 %, 40% to 100%, 100% to 180%, and 180% to 400%, as a desired converted image when the decoding device 90 performs knee conversion with high precision. Additionally, the user sets an HDR image that is obtained by knee decompressing 80% to 100% luminance of an SDR image to 80% to 400% as a desired converted image when the decoding device 90 performs simple knee conversion. with low accuracy.

[00295] In this case, in knee_function_info SEI, the same values as in Figure 30 are set as pre-conversion position information (input_knee_point) and post-conversion position information (output_knee_point) from the 0th to second elbows. In addition, the representative pre-conversion position information (representative_input_knee_point) is 800, and the representative post-conversion position information (representative_output_knee_point) is 200.

[00296] Furthermore, in the example in Figure 38, the HDR luminance range information (d_range) is 4000, the display luminance range (d_range_disp_luminance) is 800 (candela per square meter), and the compression signal ( compression_flag) is 0.

[00297] As illustrated in Figure 38, in a case where the decoding device 90 performs simple knee conversion with low precision, the decoding device 90 recognizes that the representative elbow representative_input_knee_point_PER (%) and luminance representative_output_knee_point_PER (%) of an image converted corresponding to the representative elbow are 80% according to Equation (1) above. Furthermore, the decoding device 90 recognizes that the maximum luminance value of the converted image is 400% of the HDR luminance gamma information. Additionally, the decoding device 90 knee-decompresses 80% to 100% luminance of an SDR image that is obtained as a result of decoding to 80% to 400%. Therefore, the decoding device 90 can convert the SDR image that is obtained as a result of decoding into a desired HDR image.

[00298] On the other hand, in a case where the decoding device 90 performs knee conversion with high precision, the decoding device 90 performs the same process as in Figure 30, and converts an SDR image that is obtained as a result of decoding into a desired HDR image.

[00299] As mentioned above, the representative pre-conversion position information (representative_input_knee_point) and the representative post-conversion position information (representative_output_knee_point) are included in the DR conversion information of Figure 36. Therefore, even in a case where a processing rate or a resource such as a memory capacity cannot be sufficiently ensured in the decoding device 90, knee conversion can be performed on the basis of a representative elbow. Furthermore, since representative pre-conversion position information and representative post-conversion position information are transmitted to decoding device 90, decoding device 90 does not have to generate representative pre-conversion position information. and representative post-conversion position information on the basis of pre-conversion position information and post-conversion position information of a plurality of elbows.

[00300] Furthermore, DR conversion information of Fig. 36 can be included in SEI such as tone_mapping_info_SEI other than knee_function_info SEI. Third Example of tone_mapping_info_SEI Syntax

[00301] Figure 39 is a diagram illustrating an example of tone_mapping_info_SEI syntax in a case where the DR conversion information from Figure 36 is included in tone_mapping_info_SEI.

[00302] As illustrated in Figure 39, in a case where the DR conversion information from Figure 36 is included in tone_mapping_info_SEI, tone_map_model_id is set to, for example, 5. Furthermore, in tone_mapping_info_SEI, a compression flag (compression_flag) , representative pre-conversion position information (representative_input_knee_point), representative post-conversion position information (representative_output_knee_point), HDR luminance range information (d_range), display luminance information (d_range_disp_luminance), an elbow number ( num_knee_point_minus1), and pre-conversion position information (input_knee_point) and post-conversion position information (output_knee_point) of each elbow are set in tone_mapping_info_SEI as DR conversion information.

[00303] Also, just like the tone_mapping_info_SEI in Figure 27, the HDR luminance range information (d_range) and the display luminance information (d_range_disp_luminance) may not be included in the tone_mapping_info_SEI in Figure 39. Additionally, only one of HDR luminance range information (d_range) and display luminance information (d_range_disp_luminance) may be included.

Fourth Example Syntax of knee_function_info SEI

[00304] Figure 40 is a diagram illustrating a fourth syntax example of the knee_function_info SEI established by the establishment unit 71 of Figure 16, and Figure 41 is a diagram illustrating (semantics of) each piece of information established in the knee_function_info SEI of Figure 40 .

[00305] In the knee_function_info SEI of Figure 40, different images of an SDR image can be employed as one of an encoding target image and a converted image.

[00306] Specifically, in the same way as in the case of Figure 17, a knee conversion ID (knee_function_id) and a knee conversion cancellation flag (knee_function_cancel_flag) are set in the knee_function_info SEI of Figure 40.

[00307] Furthermore, if the knee conversion cancel flag is 0, as illustrated in Figure 40, the DR conversion information is set in the knee_function_info SEI. The DR conversion information is the same as in the case of Figure 28, except that the knee conversion persistence flag (knee_function_persistence_flag) is newly included, and the unconverted display gamma information (input_d_range), display luminance information unconverted display (input_disp_luminance), converted display gamma information (output_d_range), and converted display luminance information (output_disp_luminance) are included instead of HDR luminance range information (d_range) and display luminance information (d_range_disp_luminance ). Description of the same part as in the case of Figure 28 is repeated and so will be omitted as appropriate.

[00308] As illustrated in Figure 41 , the knee conversion persistence flag is a flag indicating whether or not the DR conversion information is applied to a plurality of frames that are located continuously. The knee conversion persistence flag is set to 1 when the DR conversion information is applied to a plurality of frames that are located continuously, and it is set to 0 when the DR conversion information is applied to only one frame. The knee conversion persistence flag can also be set in the knee_function_info SEI of Figures 17, 28, 34 and 36.

[00309] Furthermore, the unconverted luminance gamma information is information indicating a 'permillage' of the maximum luminance value of a coding target image which is an unconverted image in conversion corresponding to the DR conversion information, and the Converted luminance gamma information is information indicating a maximum luminance permillage value of a converted image.

[00310] Furthermore, the unconverted display luminance information is information indicating an expected brightness value of the display unit corresponding to the maximum luminance value of an encoding target image, and the converted display luminance information is information indicating an expected display unit brightness value corresponding to the maximum luminance value of a converted image.

Fifth Example of DR Conversion Information

[00311] Figures 42 and 43 are diagrams illustrating examples of DR conversion information established in the knee_function_info SEI of Figure 40.

[00312] In the example of Figure 42, an encoding target image is an HDR image (hereinafter called a 200% HDR image) whose dynamic range is 0 to 200%. Furthermore, the user sets a 400% HDR image that is obtained as a result of respectively converting knee 0 to 120%, 120% to 160%, 160% to 180%, and 180% to 200% luminance of a 200% HDR image at 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400%, as a desired converted image. The 400% HDR image is an HDR image whose dynamic range is 0 to 400%.

[00313] In this case, in knee_function_info SEI, the same values as in Figure 30 are set as pre-conversion position information (input_knee_point) and post-conversion position information (output_knee_point) from the 0th to second elbows. Furthermore, 2000 is set as the unconverted luminance range information (input_d_range), and 4000 is set as the converted luminance range information (output_d_range).

[00314] Additionally, in the example of Figure 42, the unconverted display luminance information (input_disp_luminance) is 400 (candela per square meter), and the converted display luminance information (output_disp_luminance) is 800 (candela per square meter) . The compression flag (compression_flag) is 0.

[00315] As illustrated in Figure 42, in a case where an encoding target image is an image with a dynamic range corresponding to the unconverted luminance gamma information, and a converted image is an image with a dynamic range corresponding to the luminance gamma information, range of converted luminance, an elbow input_knee_point_PER (%) and luminance output_knee_point_PER (%) of a converted image corresponding to the elbow are defined by the following Equation (3).

[00316] Therefore, the decoding device 90 recognizes that the 0-th to second input_knee_point_PER elbows are respectively 120%, 160%, and 180% according to Equation (3). Furthermore, the decoding device 90 recognizes that the 0th and second luminances output_knee_point_PER are respectively 40%, 100%, and 180%. Additionally, the decoding device 90 recognizes that the maximum luminance value of the encoding target image is 200% of the input luminance gamma information, and the maximum luminance value of the converted image is 400% of the input luminance gamma information. exit.

[00317] In addition, the decoding device 90 respectively converts into knee 0 to 120%, 120% to 160%, 160% to 180%, and 180% to 200% of a 200% HDR image that is obtained as decoding results in 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400%, according to a straight line conversion in which the elbows are connected to each other in a set order. Then, the decoding device 90 can convert the 200% HDR image that is obtained as a result of decoding into a desired 400% HDR image.

[00318] In the example of Figure 43, an encoding target image is a 400% HDR image. In addition, the user sets a 200% HDR image that is obtained as a result of respectively converting to knee 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400% luminance of a 400% HDR image, in 0 to 120%, 120% to 160%, 160% to 180%, and 180% to 200% as a desired converted image.

[00319] In this case, in knee_function_info SEI, the same values as in Figure 31 are set as pre-conversion position information (input_knee_point) and post-conversion position information (output_knee_point) from the 0th to second elbows. Furthermore, 4000 is set as the unconverted luminance range information (input_d_range), and 2000 is set as the converted luminance range information (output_d_range).

[00320] Additionally, in the example of Figure 43, the unconverted display luminance information (input_disp_luminance) is 800 (candela per square meter), and the converted display luminance information (output_disp_luminance) is 400 (candela per square meter) . The compression flag (compression_flag) is 1.

[00321] As described above, in a case where an encoding target image is an image with a dynamic range corresponding to unconverted luminance gamma information, and a converted image is an image with a dynamic range corresponding to luminance gamma information converted luminance, an input_knee_point_PER elbow (%) and output_knee_point_PER luminance (%) of a converted image corresponding to the elbow are defined by Equation (3) above.

[00322] Therefore, the decoding device 90 recognizes that the 0-th to second input_knee_point_PER elbows are respectively 40%, 100%, and 180% according to Equation (3). Furthermore, the decoding device 90 recognizes that the 0-th to second luminances output_knee_point_PER (%) are respectively 120%, 160%, and 180%. Additionally, the decoding device 90 recognizes that the maximum luminance value of the encoding target image is 400% of the input luminance gamma information, and the maximum luminance value of the converted image is 200% of the input luminance gamma information. exit.

[00323] In addition, the decoding device 90 converts respectively 0 to 40%, 40% to 100%, 100% to 180%, and 180% to 400% of a 400% HDR image, which is obtained as a result of decoding at 0 to 120%, 120% to 160%, 160% to 180%, and 180% to 200%, connecting the elbows to each other in a set order. Therefore, the decoding device 90 can convert the 400% HDR image that is obtained as a result of decoding into a desired 200% HDR image.

[00324] As mentioned above, according to the DR conversion information of Figure 40, not only conversion between an SDR image and an HDR image, but also conversion between HDR images with different dynamic ranges can be performed as desired by a user at the decoding device 90. A dynamic range of an HDR image can be greater than 0 to 100%, and it can be 0 to 400%, 0 to 800%, 0 to 1300%, and the like. In addition, an expected display brightness value corresponding to the maximum luminance value of an HDR image can be greater than 100 (candela per square meter), and can be 800 (candela per square meter), 4000 (candela per square meter ), 1500 (candela per square meter), and similar.

Decoding Device Operation Description

[00325] Fig. 44 is a diagram illustrating an operation of the decoding device 90 in a case where the knee_function_info SEI of Fig. 40 is set to a plurality.

[00326] In an example of Figure 44, an encoding target image is a 400% HDR image. Also, knee_function_info SEI (then called 800% HDR image knee_function_info SEI) to set a desired converted image to an 800% HDR image whose dynamic range is 0 to 800%, and knee_function_info SEI (then called SDR image knee_function_info SEI) to set a desired converted image to an SDR image, are set. In this case, different knee conversion IDs are given to the 800% HDR image knee_function_info SEI and the SDR image knee_function_info SEI.

[00327] In a case where the display unit 95 is an HDR display that can display an 800% HDR image, the decoding device 90 decompresses into knee luminance a 400% HDR image that is a decoded image on the base of the 800% HDR image knee_function_info SEI, to generate a desired 800% HDR image as a display image.

[00328] On the other hand, in a case where the display unit 95 is an HDR display that can display a 400% HDR image, the decoding device 90 uses a 400% HDR image that is a decoded image as an unchanging display image. Furthermore, in a case where the display unit 95 is an SDR display, the decoding device 90 knee-compresses the luminance of a 400% HDR image which is a decoded image on the basis of the SDR image knee_function_info SEI, to generate a desired SDR image as a display image.

[00329] Furthermore, the DR conversion information of Fig. 40 can be included in SEI as tone_mapping_info_SEI other than knee_function_info SEI.

Fourth Example of tone_mapping_info_SEI Syntax

[00330] Figure 45 is a diagram illustrating an example of tone_mapping_info_SEI syntax in a case where the DR conversion information from Figure 40 is included in tone_mapping_info_SEI.

[00331] As illustrated in Figure 45, in a case where the DR conversion information from Figure 40 is included in tone_mapping_info_SEI, tone_map_model_id is set to, for example, 5. Furthermore, in tone_mapping_info_SEI, a compression flag (compression_flag) , input luminance range information (input_d_range), input display luminance range (input_d_range_disp_luminance), output luminance range information (output_d_range), output display luminance range (output_d_range_disp_luminance), an elbow number ( num_knee_point_minus1), and pre-conversion position information (input_knee_point) and post-conversion position information (output_knee_point) of each elbow are set in tone_mapping_info_SEI as DR conversion information.

[00332] In addition, at least one of the input luminance range information (input_d_range), the input display luminance range (input_d_range_disp_luminance), the output luminance range information (output_d_range), and the luminance range output display (output_d_range_disp_luminance) may not be included in the tone_mapping_info_SEI of Figure 45.

[00333] Furthermore, in the above description, the DR conversion information is arranged in SEI, but it may be arranged in a system layer. Example of Arranging DR Conversion Information in MP4 Box DESCRIPTION of MP4 Box in which DR Conversion Information Is Arranged

[00334] Fig. 46 is a diagram illustrating an MP4 box as a system layer in which DR conversion information is arranged.

[00335] As illustrated in Figure 46, in a case where DR conversion information is arranged in an MP4 box, a tinf box (Tone Mapping Information Box) that stores DR conversion information as ToneMapInfo is defined recently. The tinf box is stored in a track box (track box ) (an stbl box stored in it) or a traf box (trail fragment box).

ToneMapInfo Syntax Example

[00336] Figure 47 is a diagram illustrating an example of ToneMapInfo syntax.

[00337] Figure 47's ToneMapInfo has the same setting as that of Figure 32's tone_mapping_info_SEI, except that padding_value for byte alignment is inserted into it.

[00338] Also, although not illustrated, ToneMapInfo can have the same setting as that of the tone_mapping_info_SEI of Figure 26, 27, 39, or 45, except that padding_value for byte alignment is built into it.

[00339] Furthermore, in the same way as in the second embodiment, the conversion information in the first embodiment can be arranged in a system layer.

[00340] Furthermore, an HDR image desired by a user may be an HDR image that is input to encoding device 70.

[00341] Additionally, in the second embodiment, an HDR image is input to the encoding device 70, but an SDR image can be input thereto. In this case, when an encoding target image is an HDR image, the encoding device 70 converts an SDR image that is input from an external device into an HDR image which is then established as an encoding target image.

[00342] Furthermore, a plurality of elbows is established in the knee_function_info SEI of Figure 40. Therefore, knee conversion of a smoother and more complex function can be defined than in a case where only one elbow is established. As a result, the conversion unit 93 can perform optimal knee conversion.

[00343] However, if the number of elbows increases, an amount of DR conversion information increases. So, for example, in a case where a decoded image and DR conversion information are transmitted with HDMI, an amount of the DR conversion information is equal to or greater than 27 bytes, which is a size of an AVI InfoFrame packet. of HDMI, and thus DR conversion information may not be included in AVI InfoFrame.

[00344] Therefore, in a third embodiment described later, a decoding device performs optimum elbow thinning in a case where an amount of DR conversion information is reduced, such as a case where DR conversion information is transmitted with HDMI.

Third Modality First Example of Semantics

[00345] A first configuration of a third embodiment of an encoding device to which the present description is applied is the same as the configuration of the encoding device 70 of Figure 16, except for the order i of elbows and semantics indicated by the knee_function_info SEI of Figure 40 established by establishment unit 71. Therefore, in the following, only the order i of elbows and semantics indicated by the knee_function_info SEI of Figure 40 will be described.

[00346] In the first configuration of the third embodiment of the coding device to which the present description is applied, the order i of elbows is established in an order in which priorities for representing a desired knee conversion function are highest in the knee_function_info SEI of Figure 40.

[00347] Furthermore, Figure 48 is a diagram illustrating that semantics in the first configuration of the third embodiment of the coding device to which the present description is applied is different from that in the second embodiment.

[00348] As illustrated in Figure 48, in the semantics of Figure 40 in the first configuration of the third modality of the coding device to which the present description is applied, pre-conversion position information (input_knee_point[i]) of an i-th elbow can be equal to or less than the preconversion position information (input_knee_point[i-1]) of an (i-1)th elbow. In other words, the order i (where i is an integer of 0 or more) in which the preconversion position information and the postconversion position information of an elbow are established may not be an order in which the Post-conversion position information is less.

[00349] Also, a knee conversion function (knee function) is a straight line that connects elbows to each other in an order (ascending order) where the pre-conversion position information (input_knee_point) is less.

[00350] Additionally, a decoded image can be knee converted using an approximate knee conversion function. The approximate knee conversion function is a straight line that connects the 0th to Nth (where N is equal to or greater than 0 and equal to or less than num_knee_point_minus1) elbows to each other in an order in which the information of pre-conversion position is less. Since the order i of elbows is set in an order in which a priority for representing a desired knee conversion function is highest, an approximate knee conversion function is closer to a desired knee conversion function as N is bigger. First Configuration Example of a Decoding System Modality

[00351] Figure 49 is a block diagram illustrating a first configuration example of a modality of a decoding system to which the present description is applied and which decodes an encoded stream transmitted from the first configuration of the third modality of the encoding device to the which the present description applies.

[00352] Among constituent elements illustrated in Figure 49, the same constituent elements as the constituent elements of Figures 12 and 22 are given the same reference numerals. Repeated description will be omitted as appropriate.

[00353] A decoding system 110 of Figure 49 includes a decoding device 111 and a display device 112. The decoding device 111 includes a receiving unit 51, an extracting unit 91, a decoding unit 92, a of selection 121 and a transmission unit 122.

[00354] The selection unit 121 of the decoding device 111 acquires knee_function_info SEI between sets of parameters extracted by the extraction unit 91. The selection unit 121 selects DR conversion information from the number (for example, 3) of elbows included in a single HDMI AVI InfoFrame packet in an order in which the i-order is the lowest of the DR conversion information pieces of a plurality of elbows included in the knee_function_info SEI. The selection unit 121 provides the selected elbow DR conversion information to the transmission unit 122.

[00355] The transmission unit 122 arranges the DR conversion information selected by the selection unit 121 into a single HDMI AVI InfoFrame packet, and transmits a result thereof to the display device 112 with HDMI along with a generated decoded image by decoding unit 92.

[00356] The display device 112 includes a receiver unit 131, a conversion unit 93, a display control unit 94 and a display unit 95.

[00357] The receiving unit 131 of the display device 112 receives AVI InfoFrame and the decoded image which are transmitted from the transmitting unit 122 with HDMI. The receiver unit 131 provides the DR conversion information arranged in AVI InfoFrame and the decoded picture to the converter unit 93.

Description of the First Elbow Selection Method

[00358] Figure 50 is a diagram illustrating an example of an elbow and knee conversion function defined by the knee_function_info SEI that is received by the decoding system 110 of Figure 49.

[00359] Also, in the example in Figure 50, an elbow number (number_knee_point_minus1) established in the knee_function_info SEI is 8.

[00360] As illustrated in Figure 50A, among eight elbows set in the knee_function_info SEI, pre-conversion position information (input_knee_point [0]) of the 0-th elbow is 200, and post-conversion position information (output_knee_point [ 0]) of this is 433. In addition, pre-conversion position information (input_knee_point[1]) of the first elbow is 600, and post-conversion position information (output_knee_point[1]) of this is 774, and information of pre-conversion position (input_knee_point[2]) of the second elbow is 100, and post-conversion position information (output_knee_point[2]) of this is 290.

[00361] Additionally, pre-conversion position information (input_knee_point[3]) of the third elbow is 400, and post-conversion position information (output_knee_point[3]) of that is 628, and pre-conversion position information (input_knee_point[4]) of the fourth elbow is 800, and post-conversion position information (output_knee_point[4]) of this is 894.

[00362] In addition, pre-conversion position information (input_knee_point[5]) of fifth elbow is 300, and post-conversion position information (output_knee_point[5]) of this is 540, and pre-conversion position information conversion (input_knee_point[6]) of the sixth elbow is 500, and post-conversion position information (output_knee_point[6]) from it is 705.

[00363] In addition, pre-conversion position information (input_knee_point[7]) of the seventh elbow is 700, and post-conversion position information (output_knee_point[7]) of this is 836, and pre-conversion position information conversion (input_knee_point[8]) of the eighth elbow is 900, and post-conversion position information (output_knee_point[8]) from this is 949.

[00364] In this case, the respective elbows are connected to each other in an order in which the pre-conversion position information is less, and thus a knee conversion function is as illustrated in Figure 50B. In other words, a straight line connecting the elbows to each other in an order of the second, 0th, fifth, third, sixth, first, seventh, fourth, and eighth elbows serves as a knee conversion function. Furthermore, the transverse axis of Fig. 50B expresses luminance of an encoded target image, and the longitudinal axis expresses luminance of a converted image. This is also the same for Figures 51, 52, and 57 to 59 described later.

[00365] In a case where the selection unit 121 selects pieces of DR conversion information of three elbows from the pieces of DR conversion information of elbows defined by the knee_function_info SEI of Figure 50A, an approximate knee conversion function having the selected elbows is as illustrated in Figure 51.

[00366] In other words, in this case, the selection unit 121 selects pieces of DR conversion information from the 0th to second elbows among the pieces of DR conversion information from the 0th to eighth elbows defined by the knee_function_info SEI . Therefore, a knee conversion function having the elbows selected is a straight line that connects the 0th to second elbows to each other in an order in which the preconversion position information is less, that is, in an order of the 2nd, 0th and 1st elbows.

[00367] Meanwhile, in a case where the selection unit 121 selects pieces of DR conversion information of five elbows from among the pieces of DR conversion information of elbows defined by the knee_function_info SEI of Figure 50A, an approximate conversion function kneeling with elbows selected is as illustrated in Figure 52.

[00368] In other words, in this case, the selection unit 121 selects pieces of DR conversion information from the 0th to fourth elbows among the pieces of DR conversion information from the 0th to eighth elbows defined by the knee_function_info SEI . Therefore, a knee conversion function having the elbows selected is a straight line connecting the 0th to fourth elbows to each other in an order in which the preconversion position information is less, that is, in an order of the second, 0th, third, first and fourth elbows.

[00369] The order i of the elbows is established in an order of a priority to represent the function of Fig. 50B, which is a desired function of knee conversion is highest, and pieces of DR conversion information of a predetermined number of elbows are selected from the lowest order i. Therefore, as illustrated in Figures 51 and 52, an approximate knee conversion function is closer to the function in Figure 50B than in a case where other elbows of the same number are selected.

[00370] Furthermore, a greater number of elbows leads to a smoother and more complex function. Therefore, an approximate knee conversion function of Figure 52 in which the number of elbows is five is closer to the knee conversion function of Figure 50B than an approximate knee conversion function of Figure 51 in which the number of elbows it's three.

Description of the Decoding System Process

[00371] Fig. 53 is a flowchart illustrating a decoding process performed by the decoding device 111 of the decoding system 110 of Fig. 49.

[00372] In step S111 of Fig. 53, the receiver unit 51 of the decoding device 111 receives an encoded stream transmitted from the encoding device 70 of Fig. 16, and provides the encoded stream to the extraction unit 91.

[00373] At step S112, the extraction unit 91 extracts parameter sets and coded data from the coded stream that is provided by the receiver unit 51. The extraction unit 91 provides the parameter sets and coded data to the decoding unit 92. Furthermore, extraction unit 91 provides knee_function_info SEI among parameter sets to selection unit 121.

[00374] In step S113, the decoding unit 92 decodes the encoded data provided by the extracting unit 91 in the HEVC method. At this time, the decoding unit 92 also refers to the parameter sets provided from the extracting unit 91, as required. Decoding unit 92 provides the decoded picture to transmission unit 122.

[00375] At step S114, the selection unit 121 selects DR conversion information from the number of elbows included in a single packet of AVI InfoFrame from HDMI in an order in which order i is lowest among pieces of conversion information from DR of a plurality of elbows included in the knee_function_info SEI of the extraction unit 91. The selection unit 121 provides the DR conversion information selected from the elbow to the transmission unit 122.

[00376] At step S115, the transmission unit 122 arranges the DR conversion information selected by the selection unit 121 into a single packet of AVI InfoFrame of HDMI, and transmits a result thereof to the display device 112 with HDMI together with a decoded image generated by the decoding unit 92. Further, the process is terminated.

[00377] Figure 54 is a flowchart illustrating a display process performed by the display device 112 of the decoding system 110.

[00378] In step S131 of Fig. 54, the receiving unit 131 of the display device 112 receives the DR conversion information arranged in AVI InfoFrame and the decoded picture which are transmitted from the transmitting unit 122 with HDMI. The receiver unit 131 provides the DR conversion information and the decoded picture to the conversion unit 93.

[00379] Processes in steps S132 to S134 are the same as processes in steps S95 and S97 of Figure 23, and thus this description will not be repeated.

[00380] As mentioned above, in the first configuration of the third embodiment to which the present description is applied, the DR conversion information of the elbow in which the order is set to an order in which a priority to represent a desired knee conversion is highest is set in the knee_function_info SEI and is transmitted. Therefore, the decoding device 111 selects DR conversion information from the number of elbows included in a single AVI InfoFrame packet in an order in which order i is lowest, and thus can arrange DR conversion information of the elbow indicating a approximate knee conversion function that is closest to a desired knee conversion function in a single AVI InfoFrame package.

Syntax Example of knee_function_info SEI

[00381] A second configuration of the third embodiment of the encoding device to which the present description is applied is the same as the configuration of the encoding device 70 of Figure 16, except for the knee_function_info SEI established by the establishment unit 71 and semantics. So then only the knee_function_info SEI and semantics will be described.

[00382] Fig. 55 is a diagram illustrating an example syntax of knee_function_info SEI established by setting unit 71 in the second configuration of the third embodiment of the coding device to which the present description is applied.

[00383] The knee_function_info SEI of Figure 55 is the same as the knee_function_info SEI of Figure 40, except that an approximate elbow index (approximate_knee_point_index) (priority information) indicating the order i is established in an order in which a priority to represent a function desired knee conversion is higher.

[00384] In the knee_function_info SEI of Figure 55, the i order of elbows is an order in which the preconversion position information is less in the same way as in the case of Figure 40, but the approximate elbow index (approximate_knee_point_index) is recently established. An approximate elbow index value (approximate_knee_point_index) is equal to or less than the elbow number (number_knee_point_minus1).

Second Example of Semantics

[00385] Figure 56 is a diagram illustrating that semantics of Figure 55 are different from that of the second embodiment.

[00386] As illustrated in Figure 56, in the semantics of Figure 55, a decoded image can be converted to knee using an approximate knee conversion function. This approximate knee conversion function is a straight line connecting elbows where the order i is 0-th to N-th (where N is equal to or greater than 0 and equal to or less than num_knee_point_minus1) approximate elbow index (approximate_knee_point_index [0] to approximate_knee_point_index[N]) in an order in which order i is lowest. A j order of approximate elbow indices is an order in which a priority for representing a desired knee conversion function is highest, and thus an approximate knee conversion function is closest to a desired knee conversion function as N it's bigger.

Configuration Example of a Coding System Modality

[00387] A second configuration of a modality of the decoding system to which the present description is applied is the same as the configuration of the decoding system 110 of Fig. 49 , except that the selection by the selection unit 121 is performed not on the basis of order i of elbows, but in order j of approximate elbow indices. Therefore, in the following, only the selection by the selection unit 121 will be described.

Description of the Second Elbow Selection Method

[00388] Figures 57A and 57B are diagrams illustrating an example of an elbow and a knee conversion function defined by the knee_function_info SEI of Figure 55.

[00389] Furthermore, in the example of Figures 57A and 57B, an elbow number (number_knee_point_minus1) established in the knee_function_info SEI is 8 in the same way as in Figures 50A and 50B, and elbows are also equal as in Figures 50A and 50B. However, in the knee_function_info SEI of Figure 55, the order i of elbows is an order in which the pre-conversion position information is less, and is thus different from that of Figures 50A and 50B.

[00390] As illustrated in Figure 57A, among eight elbows set in the knee_function_info SEI, pre-conversion position information (input_knee_point [0]) of the 0-th elbow is 100, and post-conversion position information (output_knee_point [ 0]) of this is 290. In addition, pre-conversion position information (input_knee_point[1]) of the first elbow is 200, and post-conversion position information (output_knee_point[1]) of this is 433, and information of pre-conversion position (input_knee_point[2]) of the second elbow is 300, and post-conversion position information (output_knee_point[2]) of this is 540.

[00391] Additionally, pre-conversion position information (input_knee_point[3]) of the third elbow is 400, and post-conversion position information (output_knee_point[3]) of this is 628, and pre-conversion position information (input_knee_point[4]) of the fourth elbow is 500, and post-conversion position information (output_knee_point[4]) of this is 705.

[00392] In addition, the pre-conversion position information (input_knee_point[5]) of the fifth elbow is 600, and the post-conversion position information (output_knee_point[5]) of this is 774, and the pre-conversion position information -conversion (input_knee_point[6]) of the sixth elbow is 700, and post-conversion position information (output_knee_point[6]) of this is 836.

[00393] In addition, the pre-conversion position information (input_knee_point[7]) of the seventh elbow is 800, and the post-conversion position information (output_knee_point[7]) of this is 894, and the pre-conversion position information -conversion (input_knee_point[8]) of the eighth elbow is 900, and post-conversion position information (output_knee_point[8]) from it is 949.

[00394] In this case, the respective elbows are connected to each other in an order in which the order i is lowest, and thus a knee conversion function is as illustrated in Figure 57B.

[00395] Furthermore, as illustrated in Figure 57A, the approximate elbow indices (approximate_knee_point_index) where the j order is 0 to 8 are 1, 5, 0, 3, 7, 2, 4, 6, and 8 in order .

[00396] In a case where the selection unit 121 selects pieces of DR conversion information of three elbows from among the pieces of DR conversion information of elbows defined by the knee_function_info SEI of Figure 57A, a knee conversion function having the selected elbows is as illustrated in Figure 58.

[00397] In other words, in this case, the selection unit 121 selects pieces of DR conversion information from the elbows where the order i is the 0th to second approximate elbow indices (approximate_knee_point_index) from among the pieces of information from DR conversion from 0th to 8th elbows defined by knee_function_info SEI. In other words, the selection unit 121 selects the pieces of DR conversion information from the first, fifth and 0th elbows. Therefore, a knee conversion function having the elbows selected is a straight line connecting the first, fifth and 0-th elbows to each other in an order which order is lowest, i.e. in an order from 0- th, first and fifth elbows.

[00398] Meanwhile, in a case where the selection unit 121 selects pieces of DR conversion information of five elbows from among the pieces of DR conversion information of elbows defined by the knee_function_info SEI of Fig. 57A, a conversion function of knee with elbows selected is as illustrated in Figure 59.

[00399] In other words, in this case, the selection unit 121 selects pieces of DR conversion information from the elbows where the order i is the 0th to fourth approximate elbow indices (approximate_knee_point_index) from among the pieces of information from DR conversion from 0th to 8th elbows defined by knee_function_info SEI. In other words, the selection unit 121 selects the pieces of DR conversion information from the first, fifth, 0th, third and seventh elbows. Therefore, a knee conversion function having the elbows selected is a straight line that connects the first, fifth, 0-th, third and seventh elbows to each other in an order in which order i is lowest, that is, in an order of 0th, first, third, fifth and seventh elbows.

[00400] The order j of the approximate elbow indices is established in a priority order to represent the function of Figure 57B, which is a desired function of knee conversion is higher, and pieces of information of conversion of DR of elbows with a predetermined number of i-order approximate elbow indices are selected from the lowest order j. Therefore, as illustrated in Figures 58 and 59, an approximate knee conversion function is closer to the function in Figure 57B than in a case where other elbows of the same number are selected.

[00401] Furthermore, a larger number of elbows leads to a smoother and more complex function. Therefore, an approximate knee conversion function of Figure 59 in which the number of elbows is five is closer to the knee conversion function of Figure 57B than an approximate knee conversion function of Figure 58 in which the number of elbows it's three.

[00402] Furthermore, as illustrated in Figure 60, the approximate elbow index (approximate_knee_point_index) can be established in approximate_knee_function_info SEI different from knee_function_info SEI.

[00403] In this case, an approximate knee conversion ID (approximate_knee_function_id) and an approximate knee conversion cancel flag (approximate_knee_function_cancel_flag) are set in the approximate_knee_function_info SEI.

[00404] The approximate knee conversion ID is a unique ID for the purpose of knee conversion using an approximate function. In addition, the approximate knee conversion override flag is a flag illustrating whether or not persistence of the previous approximate_knee_function_info SEI is overridden. The approximate knee conversion override flag is set to 1 when indicating that persistence of previous approximate_knee_function_info SEI is off, and is set to 0 when persistence is not off.

[00405] In a case where the approximate knee conversion override flag is 0, a reference knee conversion ID (ref_knee_function_id) is set in the approximate_knee_function_info SEI. The reference knee conversion ID is a knee_function_info SEI knee conversion ID including DR information of an elbow indicating a knee conversion function that is approximated using an approximate elbow index from the approximate_knee_function_info SEI.

[00406] In addition, an approximate elbow index number (num_approximate_knee_point_indices_minus1) which is a value obtained by subtracting 1 from the approximate elbow index number, and an approximate elbow index (approximate_knee_point_index) are established.

[00407] As mentioned above, also in a case where the approximate elbow index (approximate_knee_point_index) is established in the approximate_knee_function_info SEI, semantics are the same as the semantics described in Figure 56.

[00408] Furthermore, in the above description, only the knee_function_info SEI including DR information of an elbow indicating a knee conversion function is established, but knee_function_info SEI including DR information of an elbow indicating an approximate knee conversion function can be established. In this case, for example, DR information of an elbow indicating a knee conversion function is set to knee_function_info SEI where a knee conversion ID is 0, and DR information of an elbow indicating an approximate knee conversion function is set to knee_function_info SEI where a knee conversion ID is 1. Additionally, in a case where DR information is transmitted with HDMI, the decoding device deploys the DR information included in the knee_function_info SEI where the knee conversion ID is 1, in a single AVI InfoFrame package, and transmits the DR information.

[00409] In addition, a unique ID is set in predetermined brightness as the unconverted display luminance information (input_disp_luminance) and the converted luminance gamma information (output_d_range), and thus it is possible to reduce an amount of DR information. In this case, for example, 0 might be assigned 400 candela per square meter, and 1 might be assigned 800 candela per square meter, as an ID. A correspondence relationship between an ID and named brightness with the ID is established in common to an encoding side and a display side, and thus the display side can recognize the brightness of the ID.

[00410] In the third embodiment, an elbow is selected in an order in which priorities for representing a desired knee conversion function are highest, but an elbow can be selected in other orders.

[00411] Furthermore, in the third embodiment, the number of elbows selected is the number that can be included in a single AVI InfoFrame package, but is not limited to that. For example, in a case where decoding device 111 has a function of display device 112, the number of elbows selected may be the number of elbows corresponding to the knee conversion that can be processed by the conversion unit 93, or the like.

Fourth Modality Basis of the Fourth Modality

[00412] As illustrated in Figure 61, in a cathode ray tube (CRT) used in a CRT display, an input electrical signal and display luminance have no proportional relationship, and it is necessary to introduce a higher electrical signal to in order to display high luminance. Therefore, if an electrical signal that is proportional to the luminance of an image is input to the CRT display as illustrated in Figure 62, the display luminance is lower than the original luminance of the image as illustrated in Figure 63. In order to display an image with the original luminance of the image, as illustrated in Figure 64, it is necessary to convert the luminance of an image into an electrical signal using a function having a characteristic contrary to that of the function of Figure 61.

[00413] In addition, in Figures 61 and 63, the transverse axis expresses a value obtained by normalizing an input electrical signal when a value of the input electrical signal to display with the maximum luminance on the CRT display is set to 1, and the Longitudinal axis expresses a value obtained by normalizing the display luminance when the maximum display luminance value of the CRT display is set to 1. In Figures 62 and 64, the transverse axis expresses a value obtained by normalizing the luminance of a viewed display image when the maximum luminance value of a target display image is set to 1, and the longitudinal axis expresses a value obtained by normalizing an electrical signal when a value of the electrical signal corresponding to the maximum luminance value of a target display image is set to 1.

[00414] A function to convert an electrical input signal into display luminance as illustrated in Figure 61 is called an electro-optical transfer function (EOTF), and a function to convert the luminance of an image into an electrical signal as illustrated in Figure 64 is called an electrical-optical transfer function (OETF).

[00415] Other displays such as a light-emitting diode (LED) panel have different characteristics from the characteristics of the CRT display. However, in order not to change procedures of generating an input electrical signal depending on displays, processes using EOTF and OETF are also performed in the same way as on CRT display in a case of performing display with other displays.

[00416] Figure 65 is a diagram illustrating an example of a process flow until an image is displayed from image capture.

[00417] Furthermore, in the example in Figure 65, an electrical signal is a 10-bit code value (0 to 1023), and the OETF and EOFT are defined in BT.709.

[00418] As illustrated in Figure 65, when an image is captured by a camera or similar, a photoelectric conversion process of converting luminance (light) into an electrical signal (code value) using the OETF is performed on the captured image. Then, the electrical signal is encoded, and the electrically encoded signal is decoded. Furthermore, an electro-optical conversion process of converting an electrical signal to luminance using EOTF is performed on the decoded electrical signal.

[00419] Meanwhile, the human visual sense has a characteristic of being sensitive to a luminance difference to low luminance and being insensitive to a luminance difference to high luminance. Therefore, as illustrated in Figure 65, the OETF of BT.709 is a function in which more code values are assigned to a low luminance part than a high luminance part. As a result, subjectively sufficient image quality is perceived.

[00420] In a case where the maximum luminance of an image is about 100 candela per square meter, satisfactory code values can be assigned to a low luminance part using the OETF of BT.709. However, the maximum luminance of displays has recently tended to increase, and is expected to accelerate in the future. If the maximum luminance of an image increases accordingly, code values to be assigned to a low luminance part are insufficient in the OETF of BT.709, and thus satisfactory image quality cannot be obtained.

[00421] Therefore, it is considered that a new OETF for use in an HDR image in which a ratio of code values assigned to a low luminance part is increased is generated, and thus satisfactory image quality is obtained in a HDR image. HDR. But in this case, in order to perform a photoelectric conversion process and an electro-optical conversion process, it is necessary to prepare an OETF and an EOTF for an HDR image and an OETF and an EOTF for an SDR image.

[00422] On the other hand, in a case where electro-optical conversion is performed on an SDR image using an OETF to an HDR image, grayscale expression of luminance is coarse.

[00423] For example, as illustrated in Figure 66, in a case where photoelectric conversion is performed on an SDR image using an OETF of BT.709 for an SDR image having the maximum luminance of 100 candela per square meter, the luminance of the SDR image is expressed in codes from 1024 including 0 to 1023. In contrast, as illustrated in Figure 67, in a case where photoelectric conversion is performed on an SDR image using an OETF to an HDR image having the luminance maximum of 400 candela per square meter, the luminance of the SDR image is expressed, for example, in 502 code values including 0 to 501.

[00424] Therefore, an OETF and an EOTF are preferably variable in order to assign sufficient code values to a low luminance part in both an HDR image having high maximum luminance and an SDR image having low maximum luminance. Therefore, in the fourth embodiment, knee conversion is performed before the OETF of BT.709 and after the EOTF of BT.709, and thus sufficient code values can be assigned to a low luminance part. Overview of the Photoelectric Conversion Process in the Fourth Mode

[00425] Figure 68 is a diagram illustrating an overview of a photoelectric conversion process in the fourth embodiment.

[00426] As illustrated in the left part of Figure 68, in the fourth embodiment, first, predetermined knee conversion is performed on luminance (input luminance) of a captured image. In an example of Figure 68, by knee conversion, 10% of a low luminance part of the input luminance is converted to 90% of a low luminance part of the input luminance, and 90% of a high luminance part of the input luminance. input is converted to 10% of the high luminance part of the input luminance. Therefore, there is a generation of the input luminance in which more values are assigned to the low luminance part than to the high luminance part.

[00427] Next, as illustrated in the central part of Figure 68, a photoelectric conversion process using the OETF of BT.709 is performed on the input luminance in order to generate a code value of a predetermined number of bits (10 bits in the example of Figure 68). As described above, since, in the input luminance, more values are assigned to the low luminance part than to the high luminance part, as illustrated in the right part of Figure 68, more values are assigned to code values converted from the luminance of input due to the lower luminance part of the input luminance than in the OETF of BT.709. In the example of Figure 68, 10% of the low luminance part of the input luminance is assigned the 94% code values.

[00428] As mentioned above, in the fourth embodiment, an extension of assigning code values to a low luminance part (dark part) and an extension of assigning code values to a high luminance part (luminous part) are adjusted using a knee conversion function as a parameter.

[00429] Furthermore, information about a knee conversion elbow performed on the input luminance is set in the knee_function_info SEI of Fig. 40 and is transmitted to a decoding side.

Overview of the Electro-Optical Conversion Process in the Fourth Mode

[00430] Figure 69 is a diagram illustrating an overview of an electro-optical conversion process in the fourth mode.

[00431] As illustrated in the left part of Figure 69, in the fourth embodiment, first, an electro-optical conversion process using the EOTF of BT.709 is performed on code values of a decoded image in order to generate luminance (luminance of exit). Next, as illustrated in the middle part of Figure 69, predetermined knee conversion is performed on the output luminance. In an example of Figure 68, by knee conversion, 90% of a low luminance part of the output luminance is converted to 10% of a low luminance part of the output luminance, and 10% of a high luminance part of the output luminance. output luminance is converted to 90% of a high luminance part of the output luminance.

[00432] Therefore, as illustrated in the right part of Figure 69, code values in which more values are named due to the low luminance part of the input luminance than in the EOTF of BT.709 can be converted into the same output luminance as the input luminance corresponding to the code values.

[00433] As mentioned above, in the fourth embodiment, code values in which a naming span for a low luminance part (dark part) and a naming span for a high luminance part (bright part) are set are converted into luminance using a knee conversion function as a parameter.

[00434] Furthermore, information about a knee conversion elbow performed on the output luminance is determined on the basis of information set in the knee_function_info SEI or similar transmitted from an encoding side.

Fourth Encoding Device Type Configuration Example

[00435] Figure 70 is a block diagram illustrating a configuration example of the fourth embodiment of an encoding device to which the present description is applied.

[00436] Among constituent elements illustrated in Figure 70, the same constituent elements as the constituent elements of Figure 6 or 16 are given the same reference numerals. Repeated description will be omitted as appropriate.

[00437] A configuration of an encoding device 150 of Figure 70 is different from the configuration of Figure 16 in that a quantization unit 151 is provided instead of the conversion unit 73. The encoding device 150 performs a photoelectric conversion process in a captured image that is input from an external device in order to perform encoding.

[00438] Specifically, the quantization unit 151 of the coding device 150 converts the luminance of the captured image that is input from the external device into knee. Information about a knee conversion elbow is set in knee_function_info SEI by setting unit 71. The quantization unit 151 performs a photoelectric conversion process using the OETF of BT.709 on the knee converted luminance in order to generate a code value . The quantization unit 151 provides the generated code value to the coding unit 72 as a coding target picture.

Description of the Process in the Encoding Device

[00439] Figure 71 is a flowchart illustrating a flow generation process performed by the coding device 150 of Figure 70.

[00440] In step S150 of Figure 71, the quantization unit 151 of the coding device 150 converts the luminance of a captured image that is input from an external device into knee. At step S152, the quantization unit 151 performs a photoelectric conversion process using the EOTF of BT.709 on the knee-converted luminance in order to generate a code value. The quantization unit 151 provides the generated code value to the coding unit 72 as a coding target picture.

[00441] Processes in steps S152 to S154 are the same as processes in steps S73 to S75 of Figure 21, and thus description of this will be omitted.

[00442] In step S155, the setting unit 71 sets knee_function_info SEI including information about an elbow of knee conversion performed due to the process in step S150. Setting unit 71 provides sets of parameters such as SPS, PPS, VUI and knee_function_info SEI set to coding unit 72.

[00443] In step S156, the coding unit 72 encodes the coding target picture which is provided by the conversion unit 73 in the HEVC method. Processes at steps S157 and S158 are the same as processes at steps S78 and S79 of Figure 21, and thus description thereof will be omitted.

[00444] As mentioned above, the encoding device 150 performs knee conversion before the OETF of BT.709, and thus can perform a suitable photoelectric conversion process for both an SDR image and an HDR image using the OETF of BT.709.

Fourth Decoding Device Mode Configuration Example

[00445] Fig. 72 is a block diagram illustrating an example configuration of the fourth embodiment of a decoding device to which the present description is applied and which decodes an encoded stream transmitted from the encoding device 150 of Fig. 70.

[00446] Among constituent elements illustrated in Figure 72, the same constituent elements as the constituent elements of Figure 12 or 22 are given the same reference numerals. Repeated description will be omitted as appropriate.

[00447] A configuration of a decoding device 170 of Fig. 72 is different from the configuration of the decoding device 90 of Fig. 22 in that a conversion unit 171 is provided instead of the conversion unit 93. The decoding device 170 decodes a encoded stream, and performs an electro-optical conversion process on a decoded image that is obtained as a result thereof.

[00448] Specifically, the conversion unit 171 of the decoding device 170 performs an electro-optical conversion process using the EOTF of BT.709 into a code value as a decoded picture provided by the decoding unit 92, so as to generate luminance. The conversion unit 171 performs knee conversion on the luminance on the basis of knee_function_info SEI of the extraction unit 91. The conversion unit 171 provides luminance which is obtained as a result of the knee conversion to the display control unit 94 as a display image .

Description of the Decoding Device Process

[00449] Figure 73 is a flowchart illustrating an image generation process performed by the decoding device 170 of Figure 72.

[00450] Processes in steps S171 to S173 of Figure 73 are the same as processes in steps S91 to S93 of Figure 23, and thus description of this will be omitted.

[00451] At step S174, the conversion unit 171 of the decoding device 170 performs an electro-optical conversion process using the EOTF of BT.709 into a code value as a decoded picture provided by the decoding unit 92 in order to generate luminance.

[00452] In step S175, the conversion unit 171 performs knee conversion on the luminance generated on the basis of knee_function_info SEI of the extraction unit 91. The conversion unit 171 provides luminance that is obtained as a result of the knee conversion to the control unit display 94 as a display image.

[00453] In step S176, the display control unit 94 displays the display image provided by the conversion unit 93 on the display unit 95, and ends the process.

[00454] As mentioned above, the decoding device 170 performs knee conversion after the EOTF of BT.709, and thus can perform a satisfactory electro-optical conversion process for both an SDR image and an HDR image using the EOTF of BT.709.

[00455] In addition, the maximum luminance of an encoding target image can be included in an encoded stream together with encoded data and can be transmitted to the decoding device 170 from the encoding device 150, and can be determined in advance as a value common to encoding device 150 and decoding device 170. Additionally, knee_function_info SEI can be set for each item of maximum luminance of an encoding target image.

[00456] Furthermore, in the fourth embodiment, the knee_function_info SEI of the first to third embodiments can be set. In this case, the decoding side performs knee conversion using DR conversion information, and thus it is possible to perform conversion on an image that is suitable for various luminance displays.

[00457] Furthermore, the decoding device 170 in the fourth embodiment can be divided into a decoding device and a display device in the same manner as in the third embodiment.

[00458] Additionally, in the fourth embodiment, an extension of assigning code values to a low luminance part and an extension of assigning code values to a high luminance part are adjusted using a knee conversion function as a parameter, but can be adjusted using functions other than the knee conversion function as a parameter.

[00459] Furthermore, the present description can be applied to the stroke method.

Fifth Modality Description of the Computer to which Present Description is Applied

[00460] The above described series of processes can be performed by hardware or software. When the above-described series of processes are performed by software, programs constituting the software are installed on a computer. Here, the computer includes a computer incorporated in dedicated hardware, or a general-purpose personal computer or the like that can perform various types of functions by installing various types of programs.

[00461] Figure 74 is a block diagram illustrating an example hardware configuration of a computer that executes the series of processes described above according to a program.

[00462] In the computer, a central processing unit (CPU) 201, a read-only memory (ROM) 202 and a random access memory (RAM) 203 are connected to each other by a bus 204.

[00463] The bus 204 is also connected to an input and output interface 205. The input and output interface 205 is connected to an input unit 206, an output unit 207, a storage unit 208, a communication unit 209 and a disk drive 210.

[00464] The input unit 206 includes a keyboard, a mouse, a microphone, and the like. Output unit 207 includes a display, a speaker, and the like. Storage unit 208 includes a hard disk, non-volatile memory, or the like. The communication unit 209 includes a network interface or the like. Disk drive 210 drives a removable medium 211 such as a magnetic disk, an optical disk, a magneto-optical disk, or the like.

[00465] In the computer configured in this way, the CPU 201 executes the series of processes described above, for example, loading the program stored in the storage unit 208 to the RAM 203 through the input and output interface 205 and the bus 204 and executing the program .

[00466] The program executed by the computer (CPU 201) can be recorded on the removable medium 211, for example, as a packet medium, and can be provided. In addition, the program may be provided over a wired or wireless transmission medium such as a local area network, the Internet, or a digital satellite broadcast.

[00467] On the computer, the program can be installed in the storage unit 208 through the input and output interface 205 by installing the removable medium 211 in the disk unit 210. In addition, the program can be received by the communication unit 209 through a medium of wired or wireless transmission and can be installed in the storage unit 208. Additionally, the program can be installed in the ROM 202 or storage unit 208 in advance.

[00468] Furthermore, the program executed by the computer can be a program that executes processes in a series of time according to the order described in the present specification, and can be a program that executes processes in parallel or at a necessary timing such as when accessed.

Sixth Modality Application to Multi-View Image Encoding and Multi-View Image Decoding

[00469] The above-described series of processes can be applied to multi-view image encoding and multi-view image decoding. Fig. 75 is a diagram illustrating an example of a multi-view image encoding method.

[00470] As illustrated in Figure 75, multi-view images include images to a plurality of views. The plurality of views of multi-view images include a basic view in which encoding/decoding is performed using only one image its own view, and a non-basic view in which encoding/decoding is performed using images and other views. The non-basic view can use a basic view image, and it can use other non-basic view images.

[00471] In a case of coding/decoding multi-view images as in Fig. 75, each view image is coded/decoded, and the method described above of the first embodiment can be applied for coding/decoding each view. In this way, a decoded image can be converted into a desired image with a different dynamic range.

[00472] Furthermore, in the encoding/decoding of each view, the flag or parameter used in the method of the first modality can be shared. More specifically, for example, the syntax element or similar of the knee_function_info SEI can be shared in the encoding/decoding of each view. Of course, necessary information other than these elements can be shared in the encoding/decoding of each view.

[00473] In this way, it is possible to minimize the transmission of redundant information and thus reduce the amount of transmitted information (bit rate) (ie, it is possible to minimize a reduction in coding efficiency). Multi-view Image Coding Device

[00474] Fig. 76 is a diagram illustrating a multi-view image coding device that performs the multi-view image coding described above. As illustrated in Fig. 76, the multi-view image coding device 600 includes a coding unit 601, a coding unit 602 and a multiplexer 603.

[00475] The coding unit 601 encodes a basic vision image so as to generate a basic vision image encoded stream. The coding unit 602 encodes a non-basic vision image so as to generate a non-basic vision image coded stream. The multiplexer 603 multiplexes the coded basic view picture stream generated in the coding unit 601 and the coded non-basic view picture stream generated in the coding unit 602 to generate a coded multi-view picture stream.

[00476] The coding device 10 (Figure 6) is applicable to the coding unit 601 and the coding unit 602 of the multi-view image coding device 600. In other words, in the coding of each view, an image can be encoded so that a decoded image can be converted into a desired image with a different dynamic range during decoding. Furthermore, the coding unit 601 and the coding unit 602 can perform coding (that is, a flag or a parameter can be shared) mutually using the same flags or parameters (e.g., a syntax element or the like relating to a image processing), and thus it is possible to minimize a reduction in coding efficiency.

Multi-vision Image Decoding Device

[00477] Fig. 77 is a diagram illustrating a multi-view image decoding device that performs the multi-view image decoding described above. As illustrated in Fig. 77 , the multi-view image decoding device 610 includes a demultiplexer 611, a decoding unit 612 and a decoding unit 613.

[00478] The demultiplexer 611 demultiplexes the multi-view image encoded stream in which the basic vision image encoded stream and the non-basic vision image encoded stream are multiplexed, so as to extract the vision image encoded stream basic and non-basic vision image coded stream. Decoding unit 612 decodes the encoded base view image stream extracted by demultiplexer 611 to obtain a base view image. Decoding unit 613 decodes the encoded non-basic vision image stream extracted by demultiplexer 611 to obtain a non-basic vision image.

[00479] The decoding device 50 (Figure 12) is applicable to the decoding unit 612 and the decoding unit 613 of the multi-view image decoding device 610. In other words, in the decoding of each view, a decoded image can be converted into a desired image with a different dynamic range. Furthermore, the decoding unit 612 and the decoding unit 613 can perform encoding (that is, a flag or a parameter can be shared) mutually using the same flags or parameters (e.g., a syntax element or the like relating to a image processing), and thus it is possible to minimize a reduction in coding efficiency.

Seventh Modality Application to Layer Image Encoding and Layer Image Decoding

[00480] The above-described series of processes can be applied to layer image encoding and layer image decoding. Fig. 78 illustrates an example of a layer image encoding method.

[00481] Layer image coding (scalable coding) is to generate a plurality of layers of an image and encode each layer so that image data has a scalable function with respect to a predetermined parameter. Layer image decoding (scalable decoding) is decoding corresponding to layer image encoding.

[00482] As illustrated in Figure 78, in layering an image, a single image is divided into a plurality of images (layers) with a predetermined parameter having a scalable function as a reference. In other words, layered images (layer images) include images of a plurality of layers in which predetermined parameter values are different from each other. A plurality of layers of layer images include a basic layer in which encoding/decoding is performed using only an image from its own layer, and a non-basic layer (also called an enhancement layer) in which encoding/decoding is performed using images from its own layer. other layers. The non-basic layer can use a basic layer image, and it can use other non-basic layer images.

[00483] Generally, the non-basic layer is formed by its own image and data (difference data) into a difference image with images from other layers. For example, in a case where a single image is generated as two layers including a basic layer and a non-basic layer (also called an enhancement layer), an image with lower quality than that of an original image is obtained using only data of the basic layer, and thus data from the basic layer and data from the non-basic layer are combined together in order to obtain the original image (i.e. high quality image).

[00484] An image is formed in layers as mentioned above, and thus various quality images can be obtained easily depending on circumstances. For example, image compression information of only a basic layer is transmitted to a terminal having low processing performance, such as a mobile phone, so that a moving image of which spatial and temporal resolution is low or image quality is poor. image is reproduced, and image compression information of an enhancement layer as well as a basic layer is transmitted to a terminal with high processing performance, such as a television set or a personal computer, so that a moving image of the which spatial and temporal resolution is high or image quality is high is reproduced. In this way, image compression information can be transmitted from a server depending on a terminal or network performance without performing a transcoding process.

[00485] A layer image as in the example of Fig. 78 is encoded/decoded, one image of each layer is encoded/decoded, the method described above of the first embodiment can be applied to the encoding/decoding of each layer. In this way, a decoded image can be converted into a desired image with a different dynamic range.

[00486] Furthermore, in the encoding/decoding of each layer, the flag or parameter used in the method of the first modality can be shared. More specifically, for example, the syntax element or similar of the knee_function_info SEI can be shared in the encoding/decoding of each layer. Of course, necessary information other than these elements can be shared in the encoding/decoding of each layer.

[00487] In this way, it is possible to minimize transmission of redundant information and thus reduce amount of transmitted information (bit rate) (ie, it is possible to minimize a reduction in coding efficiency). Gradable Parameters

[00488] In such layer image encoding and layer image decoding (scalable encoding and scalable decoding), a parameter having a scalable function is arbitrary. For example, a spatial resolution as illustrated in Figure 79 can be a parameter (spatial grading capability). In a case of spatial grading capability, a resolution of an image is different for each layer. In other words, in this case, as illustrated in Figure 79, each frame is generated as two layers including a basic layer of which a spatial resolution is lower than that of an original image, and an enhancement layer that allows for a spatial resolution original be obtained by combination with the basic layer. Of course, the number of layers is an example, and any number of layers can be generated.

[00489] Furthermore, as a parameter giving such scaling capability, for example, a temporal resolution can be employed (temporal scaling capability) as illustrated in Figure 80. In a case of temporal scaling capability, a frame rate it is different for each layer. In other words, in this case, as illustrated in Figure 80, each frame is generated as two layers including a basic layer of which a frame rate is lower than that of an original moving image, and an enhancement layer that allows the an original frame rate is achieved by combining with the basic layer. Of course, the number of layers is an example, and any number of layers can be generated.

[00490] Additionally, as a parameter giving such scaling capability, for example, a signal-to-noise ratio (SNR) can be employed (SNR scaling capability). In a case of SNR grading capability, an SNR is different for each tier. In other words, in this case, as illustrated in Figure 81, each frame is generated as two layers including a base layer of which an SNR is lower than that of an original image, and an enhancement layer that allows an original SNR to be obtained by combination with the basic layer. Of course, the number of layers is an example, and any number of layers can be generated.

[00491] Parameters that give grading capability can use parameters other than the examples described above. For example, as a parameter giving scaling capability, a bit depth can be used (bit depth scaling capability). In a case of bit depth scaling capability, a bit depth is different for each layer. In this case, for example, a basic layer is formed by an 8-bit image, and an enhancement layer is added to this so that a 10-bit image can be obtained.

[00492] Also, as a parameter that gives scaling capability, a chroma format can be used (chroma scaling capability). In a case of chroma grading capability, a chroma shape is different for each layer. In this case, for example, a basic layer is formed by a component image with a 4:2:0 aspect ratio, and an enhancement layer is added to this so that a component image with a 4:2:2 aspect ratio can be be obtained.

[00493] Additionally, as a parameter giving scaling capability, a dynamic range of luminance can be used (DR scaling capability). In a case of DR grading capability, a dynamic range of luminance is different for each layer. In this case, for example, a basic layer is formed by an SDR image, and an enhancement layer is added to this so that an HDR image can be obtained.

[00494] In a case of applying the above-described series of processes to the dynamic range grading capability, for example, information relating to knee decompression from an SDR image to an HDR image is established in an encoded stream of an image base layer as DR conversion information. Furthermore, information relating to knee compression of a dynamic range of luminance of an HDR image is laid down in an encoded stream of an enhancement layer image as DR conversion information.

[00495] In addition, a decoding device that can decode only a coded stream of a basic layer image and includes an HDR display, converts an SDR image that is a decoded image into an HDR image on the basis of the information of DR conversion, and sets the HDR image as a display image. On the other hand, a decoding device that can also decode an encoded stream of an enhancement layer image and includes an HDR display that can display an HDR image with a low dynamic range knee-compresses a luminance dynamic range of an HDR image which is a decoded image on the basis of DR conversion information, and sets a result thereof as a display image.

[00496] Additionally, information about decompression of a dynamic range of luminance of an HDR image can be set in an encoded stream of an enhancement layer image as DR conversion information. In this case, a decoding device, which can also decode an encoded stream of an enhancement layer image and includes an HDR display that can display an HDR image with a high dynamic range, knee-decompresses a luminance dynamic range of an HDR image which is a decoded image on the basis of DR conversion information, and sets a result thereof as a display image.

[00497] As mentioned above, the DR conversion information is laid out in an encoded stream of a basic layer image or an enhancement layer image, and thus it is possible to display an image that is more satisfactory for display performance.

Layer Image Coding Device

[00498] Fig. 82 is a diagram illustrating a layered image encoding device that performs the layered image encoding described above. As illustrated in Fig. 82 , the layered picture coding device 620 includes a coding unit 621, a coding unit 622 and a multiplexer 623.

[00499] The coding unit 621 encodes a base layer image so as to generate a base layer image encoded stream. Encoder unit 622 encodes a non-basic layer image to generate a non-basic layer image encoded stream. The multiplexer 623 multiplexes the coded base layer picture stream generated in the coding unit 621 and the coded non-basic layer picture stream generated in the code unit 622 so as to generate a coded layer picture stream.

[00500] The coding device 10 (Figure 6) is applicable to the coding unit 621 and the coding unit 622 of the layered image coding device 620. In other words, in the coding of each layer, an image can be encoded so that a decoded image can be converted into a desired image with a different dynamic range during decoding. Furthermore, the coding unit 621 and the coding unit 622 can perform control or the like of an intraprediction filter process (that is, a flag or a parameter can be shared) using the mutually same flags or parameters (e.g. example, a syntax element or similar relating to an image process), and thus it is possible to minimize a reduction in coding efficiency.

Layer Image Decoding Device

[00501] Fig. 83 is a diagram illustrating a layer picture decoding device that performs the layer picture decoding described above. As illustrated in Fig. 83 , layer picture decoding device 630 includes a demultiplexer 631, a decoding unit 632 and a decoding unit 633.

[00502] The demultiplexer 631 demultiplexes the layer picture coded stream in which the basic layer picture coded stream and the non-basic layer picture coded stream are multiplexed, so as to extract the basic layer picture coded stream and the non-basic layer image encoded stream. Decoding unit 632 decodes the encoded base layer image stream extracted by demultiplexer 631 to obtain a base layer image. The decoding unit 633 decodes the encoded non-basic layer picture stream extracted by the demultiplexer 631 to obtain a non-basic layer picture.

[00503] The decoding device 50 (Figure 12) is applicable to the decoding unit 632 and the coding unit 633 of the layer image decoding device 630. In other words, in the decoding of each layer, a decoded image can be converted into a desired image with a different dynamic range. Furthermore, the decoding unit 612 and the decoding unit 613 can perform encoding (that is, a flag or a parameter can be shared) using the mutually same flags or parameters (e.g., a syntax element or the like relating to a image processing), and thus it is possible to minimize a reduction in coding efficiency.

Eighth Modality Television Set Configuration Example

[00504] Figure 84 exemplifies a television set to which the present technology is applied. The television set 900 includes an antenna 901, a tuner 902, a demultiplexer 903, a decoder 904, a video signal processing unit 905, a display unit 906, an audio signal processing unit 907, a loudspeaker - speaker 908 and an external interface unit 909. Furthermore, the television set 900 includes a control unit 910, a user interface 911, and the like.

[00505] The tuner 902 selects a desired channel from a broadcast signal that is received by the antenna 901, demodulates the selected channel, and produces an encoded bit stream that is obtained by demodulation, to the demultiplexer 903.

[00506] The demultiplexer 903 extracts a video or audio packet from a program that is a view objective of the encoded bit stream, and outputs the data in the extracted packet to the decoder 904. Furthermore, the demultiplexer 903 provides a packet of data such as electronic program guide (EPG) to the control unit 910. Additionally, the demultiplexer or the like may perform descrambling when the encoded stream is scrambled.

[00507] The decoder 904 decodes the packet, and outputs video data and audio data generated by decoding to the video signal processing unit 905 and the audio signal processing unit 907, respectively.

[00508] The video signal processing unit 905 performs noise removal or a video process or the like as per user inputs to the video data. The video signal processing unit 905 generates video data of a program that is displayed on the display unit 906, or image data or the like by an application-based process that is provided over a network. Furthermore, the video signal processing unit 905 generates video data for displaying a menu screen such as item selection, and superimposes the video data over the video data of a program. The video signal processing unit 905 generates an excitation signal on the basis of the video data generated in this way, so as to generate the display unit 906.

[00509] The display unit 906 excites a display device (for example, a liquid crystal display element) on the basis of the excitation signal from the video signal processing unit 905 in order to display a video of a program or similar.

[00510] The audio signal processing unit 907 performs a process such as de-noising the audio data, and performs D/A conversion or amplification on the processed audio data which is then provided to the speaker 908, thereby medium producing sounds.

[00511] The external interface unit 909 is an interface for connecting to an external device or to the network, and transmits and receives data such as video data or audio data.

[00512] The control unit 901 is connected to the user interface unit 911. The user interface unit 911 is constituted by an operation switch, a remote control signal receiving portion, and the like, and provides a signal of operation corresponding to the operation of a user to the control unit 910.

[00513] The control unit 910 is formed using a central processing unit (CPU), memories, and the like. The memories store a program executed by the CPU, a variety of data that is needed by the CPU running a process, EPG data, data acquired over the network, and the like. The program stored in the memories is read and executed by the CPU, for example when the television set 900 is started. The CPU runs the program, and thus controls each unit so that the television set 900 performs an operation in response to a user's operation.

[00514] In addition, the television set 900 is provided with a bus 912 that connects the tuner 902, the demultiplexer 903, the video signal processing unit 905, the audio signal processing unit 907, the external interface 909 and control unit 910 to each other.

[00515] In the television set having the configuration, a function of the decoding device (decoding method) of the present request is provided in the decoder 904. For this reason, it is possible to convert a decoded image into a desired image with a different dynamic range .

Ninth Modality Mobile Phone Configuration Example

[00516] Figure 85 exemplifies a schematic configuration of a mobile phone to which the present description is applied. The mobile telephone 920 includes a communication unit 922, an audio codec 923, a camera unit 926, an image processing unit 927, a multiplexer/demultiplexer 928, a recording/playback unit 929, a display unit 930 and a control unit 931. These constituent elements are connected to each other by a bus 933.

[00517] Furthermore, the communication unit 922 is connected to an antenna 921, and the audio codec 923 is connected to a speaker 924 and a microphone 925. Additionally, the control unit 931 is connected to a operation 932.

[00518] The mobile phone 920 performs various operations such as transmitting and receiving audio signals, transmitting and receiving e-mails or image data, capturing an image, and recording data in various modes of operation such as a speech and a data communication mode.

[00519] In speech mode, an audio signal generated by the microphone 925 undergoes conversion into audio data or data compression in the audio codec 923, and is then provided to the communication unit 922. The communication unit 922 performs a process modulation or a frequency conversion process on audio data in order to generate a broadcast signal. Additionally, communication unit 922 transmits the transmission signal to antenna 921 in order to transmit the transmission signal to a base station (not shown). Furthermore, communication unit 922 performs amplification, a frequency conversion process, and a demodulation process on a signal that is received by antenna 921, and provides the generated audio data to audio codec 923. audio 923 performs data decompression on the audio data or converts the audio data into an analog audio signal, and outputs the generated audio signal to speaker 924.

[00520] Additionally, in the data communication mode, in a case of transmitting a mail, the control unit 931 receives input text data using the operation unit 932, and displays the input text on the display unit 930. Furthermore, the control unit 931 generates mail data in response to an instruction made by the user using the operation unit 932, and provides the generated mail data to the communication unit 922. The communication unit 922 performs a process of modulation or a frequency conversion process on the mail data, and transmits the generated transmission signal from the antenna 921. Additionally, the communication unit 922 performs amplification, a frequency conversion process, and a demodulation process on a signal that is received by antenna 921 so as to retrieve mail data. Mail data is provided to display unit 930, and thus mail content is displayed.

[00521] Furthermore, the mobile telephone 920 can store the received mail data on a recording medium using the recording/playback unit 929. The recording medium is any rewritable recording medium. For example, the recording medium is a semiconductor memory such as RAM or built-in flash memory, or a removable medium such as a hard disk, magnetic disk, magneto-optical disk, optical disk, bus memory universal serial port (USB), or a memory card.

[00522] In a case where image data is transmitted in the data communication mode, image data generated by the camera unit 926 is provided to the image processing unit 927. The image processing unit 927 performs an encoding process into the image data in order to generate encoded data.

[00523] Additionally, the multiplexer/demultiplexer 928 multiplexes the image stream that was generated by the image processing unit 927 and the audio data that is provided by the audio codec 923, and provides the multiplexed data to the communication unit 922 The communication unit 922 performs a modulation process or a frequency conversion process on the multiplexed data, and transmits an acquired transmission signal to the antenna 921. frequency conversion, and a demodulation process on a signal that is received by antenna 921 in order to recover multiplexed data. The multiplexed data is provided to multiplexer/demultiplexer 928. Multiplexer/demultiplexer 928 demultiplexes the multiplexed data, and provides encoded data to image processing unit 927 and audio data to audio codec 923. Image processing unit 927 decodes the encoded data to generate image data. Image data is provided to display unit 930 to enable display of the received image. Audio codec 923 converts the audio data into an analog audio signal which is then provided to speaker 924 to produce a received sound.

[00524] In the mobile phone apparatus having the configuration, functions of the encoding device and the decoding device (the encoding method and the decoding method) of the present application are provided in the image processing unit 927. For this reason, an image can be encoded such that a decoded image can be converted into a desired image with a different dynamic range during decoding. Furthermore, it is possible to convert a decoded image into a desired image with a different dynamic range. Tenth Modality

Recording/Playback Device Configuration Example

[00525] Figure 86 exemplifies a schematic configuration of a recording/reproduction apparatus to which the present technology is applied. Recording/playback apparatus 940 records, for example, audio data and video data of a received broadcast program onto a recording medium, and provides the recorded data to a user at a time in response to a user instruction. Furthermore, recording/playback apparatus 940 can acquire, for example, audio data and image data from other apparatus, and can record the data onto the recording medium. Additionally, recording/playback apparatus 940 encodes and outputs the audio data or video data recorded onto the recording medium so that image display or sound output can be performed on a monitor device.

[00526] The recording/playback apparatus 940 includes a tuner 941, an external interface unit 942, an encoder 943, a hard disk drive (HDD) 944, a disk drive 945, a selector 946, a decoder 947, a screen display (OSD) unit 948, a control unit 949 and a user interface unit 950.

[00527] Tuner 941 selects a desired channel from a broadcast signal that is received by an antenna (not shown). Furthermore, tuner 941 produces an encoded bit stream which is obtained by demodulating the received signal from the desired channel to selector 946.

[00528] The external interface unit 942 includes any one of an IEEE1394 interface, a network interface, a USB interface, a flash memory interface, or the like. The external interface unit 942 is an interface that is connected to an external device, a network, a memory card, or the like, and receives data such as video data or audio data to be recorded.

[00529] The encoder 943 encodes video data or audio data in a predetermined method in a case where the video data and audio data provided from the external interface unit 942 are not encoded, and produces an encoded bit stream for the 946 selector.

[00530] The HDD unit 944 records content data such as video and sound, various programs, and other data on a built-in hard disk, and reads the data from the hard disk when the video and sound are played back.

[00531] Disc drive 945 records and plays data to and from an optical disc that is installed therein. The optical disc can be, for example, a DVD disc (DVD-Video, DVD-RAM, DVD-R, DVD-RW, DVD+R, DVD+RW, or similar), a Blu-ray disc (brand registered), or similar.

[00532] When a video and sound are recorded, the selector 946 selects an encoded bitstream that is input from the tuner 941 or the encoder 943, and outputs the selected encoded bitstream to the HDD unit 944 or the disk 945. Further, when a video and sound are played, selector 946 produces an encoded bitstream that is output from HDD unit 944 or disk unit 945 to decoder 947.

[00533] The decoder 947 decodes the encoded bit stream. Additionally, decoder 947 provides video data generated by the decoding process to OSD unit 948. Additionally, decoder 947 outputs audio data generated by the decoding process.

[00534] The OSD unit 948 generates video data to display a menu screen such as item selection, and superimposes and outputs the video data on top of video data that is output from the decoder 947.

[00535] The control unit 949 is connected to the user interface unit 950. The user interface unit 950 consists of an operation switch, a remote control signal receiving portion, and the like, and provides a signal of operation corresponding to the operation of a user to the control unit 949.

[00536] The control unit 949 is formed using a central processing unit (CPU), memories, and the like. The memories store a program executed by the CPU, a variety of data that is needed by the CPU running a process, EPG data, data acquired over the network, and the like. The program stored in the memories is read and executed by the CPU at a predetermined timing, for example, when recording/playback apparatus 940 is started. The CPU executes the program, and thus controls each unit so that the recording/playback apparatus 940 performs an operation in response to a user's operation.

[00537] In the recording/reproduction apparatus having the configuration, a function of the decoding device (decoding method) of the present request is provided in the decoder 947. For this reason, it is possible to convert a decoded image into a desired image with a gamma different dynamics.

Eleventh Modality Image Formation Device Configuration Example

[00538] Figure 87 exemplifies a schematic configuration of an image formation apparatus to which the present technology is applied. Image forming apparatus 960 captures an image of a subject, and displays the subject image on a display unit or records the image onto a recording medium as image data.

[00539] The image forming apparatus 960 includes an optical block 961, an image forming unit 962, a camera signal processing unit 963, an image data processing unit 964, a display unit 965, an external interface unit 966, a memory unit 967, a media unit 968, an OSD unit 969 and a control unit 970. Furthermore, the control unit 970 is connected to a user interface 971. Additionally, the image data processing unit 964, the external interface unit 966, the memory unit 967, the media unit 968, the OSD unit 969, the control unit 970, and the like are connected to each other by a bus 972.

[00540] The optical block 961 includes a focusing lens, a diaphragm mechanism, and the like. The optical block 961 forms an optical image of a subject on an imaging surface of the imaging unit 962. The imaging unit 962 includes an image sensor such as a CCD or CMOS, and generates a signal corresponding to the optical image by photoelectric conversion, and provides the electrical signal to the camera signal processing unit 963.

[00541] The camera signal processing unit 963 performs various camera signal processes, such as knee correction, gamma correction, and color correction, on the image signal that is input from the image forming unit 962. camera signal processing unit 963 provides the image data having undergone camera signal processes to the image data processing unit 964.

[00542] The image data processing unit 964 encodes the image data that is provided by the camera signal processing unit 963. The image data processing unit 964 provides encoded data generated by the encoding process to the image data processing unit 964. external interface 966 or to the drive means 968. Additionally, the image data processing unit 964 decodes the encoded data that is provided from the external interface unit 966 or the medium unit 968. Furthermore, the data processing unit The image data processing unit 964 provides image data generated by the decoding process to the display unit 965. Furthermore, the image data processing unit 964 provides image data that is provided from the camera signal processing unit 963 to the image processing unit 964. display 965, or overlays display data that is acquired from OSD unit 969 over image data that is then output to display unit 965.

[00543] The OSD unit 969 generates and outputs display data such as a menu screen formed by symbols, characters, or figures, or an icon, to the image data processing unit 964.

[00544] The external interface unit 966 is formed, for example, by a USB input and output terminal, and is connected to a printer when an image is printed. In addition, the external interface unit 966 is connected to a disk drive as needed. A removable medium such as a magnetic disk or an optical disk is installed in the disk drive as appropriate, and a computing program read from the removable medium is installed therein as necessary. Additionally, external interface unit 966 includes a network interface that is connected to a predetermined network such as a LAN or the Internet. Control unit 970 can read encoded data from media unit 968, for example in response to an instruction from user interface 971, and can provide the encoded data to other apparatus that are connected thereto over the network from the interface unit. 966. Furthermore, the control unit 970 can acquire coded data or image that is provided from other apparatus over the network, by the external interface unit 966, and can provide the data to the image data processing unit 964.

[00545] A recording medium driven by the media drive 968 can be any readable and recordable removable medium such as a magnetic disk, a magneto-optical disk, an optical disk, or a semiconductor memory. Furthermore, the recording medium can be any type of removable medium, it can be a tape device, it can be a disk, and it can be a memory card. Of course, a contactless integrated circuit (CI) card or similar can be used.

[00546] Additionally, the medium unit and a recording medium may be formed integrally to be constituted by a non-portable storage unit such as a built-in hard disk drive or a solid state drive (SSD).

[00547] The control unit 970 is formed using a CPU. Memory unit 967 stores a program executed by control unit 970, a variety of data that is needed in control unit 970 executing a process, and the like. The program stored in memory unit 967 is read and executed by control unit 970 at a predetermined timing, for example when imaging apparatus 960 is started. The control unit 970 runs the program, and thus controls each unit so that the image forming apparatus 960 performs an operation responsive to a user's operation.

[00548] In the image forming apparatus having the configuration, functions of the encoding device and the decoding device (the encoding method and the decoding method) of the present application are provided in the image data processing unit 964. For this reason, an image can be encoded so that a decoded image can be converted into a desired image with a different dynamic range during decoding. Furthermore, it is possible to convert a decoded image into a desired image with a different dynamic range.

Gradable Coding Application Examples First System

[00549] Next, a description will be made of a specific example of using scalable encoded data (encoded layer) that is scalable encoded. Scalable coding is used, for example, to select data to be transmitted as in an example illustrated in Figure 88.

[00550] In a data transmission system 1000 illustrated in Figure 88, a delivery server 1002 reads the scalable coded data stored in the scalable coded data storage unit 1001, and delivers the scalable coded data to terminal devices such as a computer personal 1004, an AV device 1005, a tablet device 1006 and a mobile phone 1007 over a network 1003.

[00551] At this time, the delivery server 1002 selects and transmits encoded data with appropriate quality on the basis of terminal apparatus performances, communication circumstances, or the like. If the delivery server 1002 unnecessarily transmits high quality data, it cannot be said that a high quality image is obtained at the terminal apparatus, and there is a concern that delay or overflow may occur. In addition, there is a concern that high quality data may unnecessarily occupy communication bandwidth, and may unnecessarily increase a load on the terminal apparatus. Conversely, if the delivery server 1002 unnecessarily transmits low quality data, there is a concern that an image of sufficient image quality cannot be obtained at the terminal apparatus. For this reason, the delivery server 1002 reads and transmits encoded data with a quality (layer) that is satisfactory for the performances of the terminal apparatuses or the communication circumstances of the scalable encoded data storage unit 1001.

[00552] Here, it is assumed that the scalable encoded data storage unit 1001 stores scalable encoded data (BL+EL) 1011 that is scalable encoded. The scalable encoded data (BL+EL) 1011 is encoded data including both a basic layer and an enhancement layer, and is data that allows obtaining both a basic layer image and an enhancement layer image by decoding.

[00553] The delivery server 1002 selects an appropriate layer on the basis of a performance of a terminal apparatus to which data is transmitted or communication circumstances, and reads data from the layer. For example, the delivery server 1002 reads the high quality encoded scalable (BL+EL) encoded data 1011 from the scalable encoded data storage unit 1001, and transmits the data as-is to the personal computer 1004 or storage device. 1006 tablet having a high processing performance. In contrast, for example, to the AV apparatus 1005 or the mobile phone 1007 having a low processing performance, the delivery server 1002 extracts base layer data from the scalable encoded data (BL+EL) 1011, and transmits the data as scalable (BL) encoded data 1012 which is the same content data as the scalable (BL+EL) encoded data 1011 in terms of content, but has lower quality than the scalable (BL+EL) encoded data 1011

[00554] As mentioned above, since an amount of data can be adjusted easily using the scalable encoded data, it is possible to minimize the occurrence of delay or overflow or to minimize an unnecessary increase in a load on a terminal apparatus or a communication medium. Furthermore, redundancy between layers is reduced in the scalable encoded data (BL+EL) 1011, and thus an amount of data thereof can be reduced further than in a case where encoded data from each layer is used as separate data. Therefore, a storage region of the scalable encoded data storage unit 1001 can be used more efficiently.

[00555] Furthermore, various devices such as the personal computer 1004 to the mobile phone 1007 can be employed as terminal devices and thus hardware performances of the terminal devices are different depending on the devices. Additionally, there are various applications that are run by the terminal devices, and thus there are also various software performances thereof. Furthermore, all communication line networks including a wired network, a wireless network, or both networks such as, for example, the Internet or a local area network (LAN) can be employed as network 1003, which is a means of communication, and there are various performances of data transmission. Furthermore, there is concern that data transmission performance may vary depending on other circumstances of communication or the like.

[00556] Therefore, before starting the data transmission, the delivery server 1002 can perform communication with a terminal apparatus that is a data transmission destination, in order to obtain information regarding the performances of the terminal apparatus such as a performance of terminal apparatus hardware and a performance of an application (software) executed by the terminal apparatus, and information relating to communication circumstances such as available network bandwidth 1003. Furthermore, the delivery server 1002 may select an appropriate layer in the basis of the information obtained here.

[00557] Additionally, the extraction of a layer can be performed by the terminal device. For example, personal computer 1004 can decode transmitted scalable encoded data (BL+EL) 1011 so as to display a basic layer image and display an enhancement layer image. Further, for example, the personal computer 1004 can extract the base layer scalable (BL) encoded data 1012 from the transmitted scalable encoded data (BL+EL) 1011 in order to store the data, transmit the data to other devices, or decode the data to display a basic layer image.

[00558] Of course, the number of scalable encoded data memory units 1001, the number of delivery servers 1002, the number of networks 1003, and the number of terminal appliances are all arbitrary. Furthermore, in the above description, a description has been made of an example in which the delivery server 1002 transmits data to the terminal apparatus, but a usage example is not limited thereto. The data transmission system 1000 is applicable to any system as long as the system selects and transmits an appropriate layer on the basis of a terminal apparatus performance, communication circumstances, or the like when encoded data is scalably encoded and transmitted to the terminal device.

Second System

[00559] Scalable coding is used, for example, for transmission using a plurality of media as in an example illustrated in Figure 89.

[00560] In a data transmission system 1100 illustrated in Figure 89 , a broadcast station 1101 transmits base layer (BL) scalable encoded data 1121 using a terrestrial broadcast 1111. Furthermore, the broadcast station 1101 transmits (e.g. , packages, and transmits) scalable enhancement layer (EL) encoded data 1122 over any network 1112 formed by a wired network, a wireless network, or both networks.

[00561] A terminal apparatus 1102 has a function of receiving the terrestrial broadcast 1111 that is broadcast by the broadcasting station 1101, and receives the base layer (BL) scalable encoded data 1121 that is transmitted by the terrestrial broadcast 1111. Terminal apparatus 1102 further has a communication function of performing communication using network 1112, and receives the enhancement layer (EL) scalable encoded data 1122 that is transmitted over network 1112.

[00562] The terminal apparatus 1102 can decode the base layer (BL) scalable encoded data 1121 that is acquired by terrestrial broadcasting 1111, for example, in response to a user instruction, so as to obtain a base layer picture, store the image, and transmit the image to other devices.

[00563] Furthermore, for example, in response to an instruction from a user, the terminal apparatus 1102 may combine the base layer (BL) scalable coded data 1121 that is acquired by the terrestrial broadcasting 1111 with the non-layer scalable coded data base layer (EL) 1122 that are acquired by the network 1112 to obtain scalable encoded data (BL+EL), and can decode the data to obtain a base layer image, store the image, and transmit the image to other devices .

[00564] As mentioned above, scalable encoded data can be transmitted over a communication medium that is different for each layer, for example. In this case, a load can be distributed, and thus it is possible to minimize the occurrence of delay or overflow.

[00565] In addition, a communication medium used for transmission can be selected for each layer depending on circumstances. For example, the base layer (BL) scalable encoded data 1121 having a relatively large amount of data can be transmitted over a communication medium having a wide bandwidth, and the enhancement layer (EL) scalable encoded data 1122 having a relatively small amount of data can be transmitted over a communication medium having a narrow bandwidth. Also, for example, a communication means for transmitting the enhancement layer (EL) scalable encoded data 1122 can be switched between the network 1112 and the terrestrial broadcast 1111 depending on an available bandwidth of the network 1112. it is also the same for data from any layer.

[00566] The control is performed as mentioned above, and thus it is possible to additionally minimize an increase in a load in data transmission.

[00567] Of course, the number of layers is arbitrary, and the number of media used for transmission is also arbitrary. Additionally, the number of terminal apparatus 1102 serving as a data transmission destination is also arbitrary. Furthermore, in the above description, the description has been made of broadcasting from the broadcasting station 1101 as an example, but a usage example is not limited to this. The data transmission system 1100 is applicable to any system as long as the system divides encoded data that is scalably encoded into a plurality of data items in the layer unit and transmits the data items over a plurality of lines.

Third System

[00568] Scalable coding is used, for example, to store coded data as in an example illustrated in Figure 90.

[00569] In an image forming system 1200 illustrated in Figure 90, an image forming apparatus 1201 scalably encodes image data that is obtained by viewing a subject 1211, and provides resulting data to an encoded data storage device scalable 1202 as scalable encoded data (BL+EL) 1221.

[00570] The scalable coded data storage device 1202 stores the scalable coded data (BL+EL) 1221 which is provided by the image forming apparatus 1201, with quality based on circumstances. For example, in a normal time case, the scalable encoded data storage device 1202 extracts base layer data from the scalable encoded data (BL+EL) 1221, and stores the data as scalable base layer encoded data (BL) 1222 having a small amount of data with low quality. In contrast, for example, in a case of notification time, the scalable coded data storage device 1202 stores the scalable coded data (BL+EL) 1221 having a large amount of data with high quality as is.

[00571] Therefore, since the scalable coded data storage device 1202 can preserve a high quality image as needed only, it is possible to minimize an increase in an amount of data while minimizing a reduction in the value of an image due to deterioration of image quality, and thus improve the efficiency of using a storage region.

[00572] For example, imaging apparatus 1201 is assumed to be a surveillance camera. In a case (a case of normal weather) where a monitoring target (e.g. an offender) is not reflected in a captured image, there is a high probability that content of the captured image may not be important, and thus a reduction in a amount of data is prioritized, and image data (scalable encoded data) is stored at low quality. In contrast, in a case (a notification timing case) where a monitoring objective is reflected in a captured image such as theme 1211, there is a high probability that content of the captured image may be important, and thus image quality is prioritized. , and image data (scalable encoded data) is stored in high quality.

[00573] Furthermore, the normal time and the notification time can be determined, for example, by the scalable coded data storage device 1202 analyzing an image. Additionally, the normal time and the notification time can be determined, for example, by the image forming apparatus 1201, and a determination result can be transmitted to the scalable coded data storage device 1202.

[00574] In addition, a criterion for determining the normal time and the notification time is arbitrary, and content of a captured image that is used as a determining criterion is arbitrary. Of course, conditions other than the content of a captured image can be used as a determining criterion. For example, the normal time and the notification time can be changed on the basis of the magnitude, a waveform, or the like of a recorded sound, and can be changed, for example, for every predetermined time interval, or by an instruction external such as an instruction from a user.

[00575] Furthermore, in the above description, an example of changing two states including normal time and notification time has been described, but the number of states is arbitrary, and, for example, three or more states such as normal time , the light notification time, the notification time, the big notification time, can be changed. Here, an upper bound number of changed states depends on the number of scalable encoded data layers.

[00576] Furthermore, the imaging apparatus 1201 can determine the number of scalable coded layers on the basis of a state. For example, in a normal time case, the imaging apparatus 1201 can generate the base layer (BL) scalable encoded data 1222 having a small amount of data with low quality, and can provide the data to the data storage device. scalable encoded data 1202. Additionally, for example, in a case of notification time, the imaging apparatus 1201 can generate the basic layer and non-basic layer (BL+EL) scalable encoded data 1221 having a large amount of data with high quality, and can provide the data to the scalable encoded data storage device 1202.

[00577] In the above description, the description was made of the monitoring camera as an example, but use of the 1200 image formation system is arbitrary and is not limited to a monitoring camera.

Twelfth Modality Another examples

[00578] In the above description, examples of devices or systems to which the present technology is applied have been described, but the present technology is not limited to this, and can be realized by all configurations mounted on a device forming the device or system , for example, a processor as a large-scale system integration (LSI) or similar, a module using a plurality of processors, a unit using a plurality of modules, an apparatus in which other functions are added to the unit, and the like (a configuration of a part of an apparatus).

Video Device Configuration Example

[00579] With reference to Figure 91, description will be made of an example in which the present technology is performed by an apparatus. Figure 91 illustrates an example of a schematic configuration of a video device to which the present technology is applied.

[00580] Multi-functioning of an electronic apparatus has recently progressed, and thus there are many cases where, when a partial configuration is sold or provided in the development or manufacture thereof, not only is a configuration having a single function realized, but also an apparatus having a plurality of functions by combining a plurality of configurations having related functions is implemented.

[00581] A video apparatus 1300 illustrated in Figure 91 has a multifunctional configuration, and is one in which a device having a function relating to encoding or decoding (one or both of encoding or decoding may be used) of an image is combined with a device having other functions related to the function.

[00582] As illustrated in Figure 91, the video apparatus 1300 includes a group of modules such as a video module 1311, an external memory 1312, a power management module 1313 and a front end module 1314, and devices having related functions such as connectivity 1321, camera 1322 and sensor 1323.

[00583] Module is a component having a unified function by collecting several mutually related component functions. A specific physical configuration of the module is arbitrary, and, for example, a plurality of processors having each function, electronic circuit elements such as resistors and capacitors, other devices, and the like can be arranged on a wiring board and integrally formed. Furthermore, a module can be combined with other modules, processors, or the like, to form a new module.

[00584] In a case of the example of Figure 91, the video module 1311 is a combination of configurations having functions related to image processing, and includes an application processor, a video processor, a broadband modem 1333 and a 1334 RF module.

[00585] The processor is one in which configurations having predetermined functions are integrated into a semiconductor chip using a system on a chip (SoC), and there may be a processor that is called, for example, large-scale system integration (LSI ). Configurations having predetermined functions may be logic circuitry (hardware configuration), may be a CPU, ROM, RAM, and the like, and programs (software configuration) executed using the configurations, and may be a combination of both. from that. For example, the process includes a logic circuit, a CPU, a ROM, a RAM, and the like, some functions can be performed by the logic circuit (hardware configuration), and other functions can be performed by the program (software configuration) executed by the CPU.

[00586] Application processor 1331 of Figure 91 is a processor that runs an application related to image processing. The application executed by the application processor 1331 may perform a calculation process in order to perform a predetermined function, and may also control constituent elements inside and outside the video module 1311, such as the video processor 1332.

[00587] The video processor 1332 is a processor having a function related to encoding/decoding (one or both thereof) of an image.

[00588] The 1333 broadband modem is a processor (or a module) that performs a process related to broadband communication over wires or wireless (or both thereof) that is performed over a broadband line such as the Internet or a public telephone line. For example, broadband modem 1333 digitally modulates data to be transmitted (digital signal) for conversion to an analog signal, or demodulates a received analog signal for conversion to data (digital signal). For example, broadband modem 1333 can digitally modulate/demodulate any information such as image data processed by video processor 1332, a stream in which the image data is encoded, an application program, or setup data.

[00589] The 1334 RF module is a module that performs frequency conversion, modulation/demodulation, amplification, filtering, and the like on a radio frequency (RF) signal that is transmitted and received by an antenna. For example, RF module 1334 performs frequency conversion or the like on a baseband signal generated by broadband modem 1333 in order to generate an RF signal. Also, for example, RF module 1334 performs frequency conversion or the like on an RF signal that is received by front end module 1314, so as to generate a baseband signal.

[00590] Additionally, in Figure 91, as indicated by a dotted line 1341, the application processor 1331 and the video processor 1332 can be integrally formed to configure a single processor.

[00591] The external memory 1312 is a module that is provided outside the video module 1311 and includes a storage device used by the video module 1311. The external memory storage device 1312 can be implemented in any physical configuration, but it is generally used to store a large volume of data such as frame unit image data, and is thus preferably implemented by a large capacity semiconductor memory which is relatively inexpensive, such as dynamic random access memory (DRAM).

[00592] The power management module 1313 manages and controls the power that is provided to the video module 1311 (each constituent element in the video module 1311).

[00593] The front end module 1314 is a module that provides a front end function (a circuit at one end transmitting and receiving one side of the antenna) for the RF module 1334. As illustrated in Figure 91, the module front end 1314 includes, for example, an antenna portion 1351, a filter 1352 and an amplification portion 1353.

[00594] The antenna portion 1351 includes an antenna and peripheral constituent elements that transmit and receive a wireless signal. The antenna portion 1351 transmits a signal that is provided by the amplification portion 1353 as a wireless signal, and provides the received wireless signal to the filter 1352 as an electrical signal (RF signal). The filter 1352 performs a filter process on the received RF signal that is received by the antenna portion 1351, and provides a processed RF signal to the RF module 1334. The amplification portion 1353 amplifies the RF signal provided by the RF module 1334, and provides the amplified signal to the antenna portion 1351.

[00595] The 1321 connectivity is a module having a function related to connection to an external device. A physical configuration of 1321 connectivity is arbitrary. For example, connectivity 1321 includes a constituent element having a communication function different from a communication standard supported by broadband modem 1333, an external input and output terminal, and the like.

[00596] For example, 1321 connectivity may include a module having a communication function conforming to a wireless communication standard such as Bluetooth (trademark) or IEEE 802.11 (e.g., Wireless Fidelity (Wi-Fi, trademark) registered), near-field communication (NFC), or Infrared Data Association (IrDA)), an antenna that transmits and receives a signal conforming to the standard, and the like. Also, for example, the 1321 connectivity may include a module having a communication function conforming to a wired communication standard such as Universal Serial Bus (USB) or High Definition Multimedia Interface (HDMI) (trademark), or a terminal conforming to the standard. Additionally, for example, connectivity 1321 may have other functions of transmitting data (signal) at an analog input and output terminal or the like.

[00597] In addition, connectivity 1321 may include a device from a data (signal) transmission destination. For example, connectivity 1321 may include a disk drive (including not only a removable media drive, but also a hard drive, solid state drive (SSD), and network attached storage (NSA)) that performs read or writing data to or from a recording medium such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory. Additionally, connectivity 1321 may include an image or sound output device (a monitor, a speaker, or the like).

[00598] The camera 1322 is a module having a function of capturing an image of a subject, and acquiring image data from the subject. Image data acquired by camera 1322 capturing an image of the subject is provided, for example, to video processor 1332, and is encoded.

[00599] The sensor 1323 is a module having any sensor function, such as an audio sensor, an ultrasonic sensor, an optical sensor, an illuminance sensor, an infrared sensor, an image sensor, an rotation, an angle sensor, an angular velocity sensor, a velocity sensor, an acceleration sensor, a tilt sensor, a magnetic ID sensor, an impact sensor, or a temperature sensor. Data detected by sensor 1323 is provided, for example, to application processor 1331, and is used by an application or the like.

[00600] In the above description, a configuration described as a module can be realized as a processor, and conversely, a configuration described as a processor can be realized as a module.

[00601] In the video apparatus 1300 having the configuration described above, the present description is applicable to the video processor 1332 as described later. Therefore, the video apparatus 1300 can be implemented as an apparatus to which present technology is applied.

Video Processor Configuration Example

[00602] Figure 92 illustrates an example of a schematic configuration of the video processor 1332 (Figure 91) to which the present technology is applied.

[00603] In an example case of Fig. 92, the video processor 1332 has a function of receiving a video signal and an audio signal and encoding the signals in a predetermined method, and a function of decoding encoded video data and data audio signal in order to reproduce a video signal and an audio signal.

[00604] As illustrated in Figure 92, the video processor 1332 includes a video input processing portion 1401, a first image enlargement/reduction portion 1402, a second image enlargement/reduction portion 403, a video output processing 1404, a frame memory 1405, and a control portion of memory 1406. In addition, the video processor 1332 includes an encoding/decoding machine 1407, video elementary stream (ES) buffers 1408A, and 1408B, and audio IO buffers 1409A and 1409B. Additionally, the video processor 1332 includes an audio encoder 1410, an audio decoder 1411, a multiplexer (MUX) 1412, a demultiplexer (DMUX) 1413, and a stream buffer 1414.

[00605] The video input processing portion 1401 acquires a video signal that is input from, for example, connectivity 1321 (Figure 91) or the like, and converts the video signal into digital image data. The first image enlargement/reduction portion 1402 performs format conversion or an image enlargement or reduction process on the image data. The second image enlargement/reduction portion 1403 performs an image enlargement or reduction process as per a format at a destination of a video which is produced by the video output processing portion 1404 on the image data, or performs the same conversion format or image enlargement or reduction process as in the first image enlargement/reduction portion 1402 in the image data. The video output processing portion 1404 performs format conversion, conversion to an analog signal, or the like on the image data, and outputs a signal converted to, for example, connectivity 1321 (Figure 91) or the like as a video signal. video played.

[00606] The frame memory 1405 is a memory for image data, shared by the video input processing portion 1401, the first image enlargement/reduction portion 1402, the second image enlargement/reduction portion 1403, the video output process portion 1404, and by the encoding/decoding machine 1407. The frame memory 1405 is implemented by a semiconductor memory such as a DRAM.

[00607] The memory control portion 1406 receives a synchronization signal from the encoding/decoding machine 1407, and controls write/read access to the frame memory 1405 according to a program for accessing the frame memory 1405, written in an access administration table 1406A. The access management table 1406A is updated by the memory control portion 1406 as per processes performed by the encoding/decoding machine 1407, the first image enlargement/reduction portion 1402, the second image enlargement/reduction portion 1403, and similar.

[00608] The encoding/decoding machine 1407 performs an encoding process on image data, and a decoding process on a video stream which is data encoded from image data. For example, encoding/decoding machine 1407 encodes image data read from frame memory 1405, and sequentially writes the encoded image data to video ES buffer 1408A as a video stream. Also, for example, video streams are read sequentially from video IO buffer 1408B in order to be decoded, and are sequentially written to frame memory 1405 as picture data. Encoding/decoding machine 1407 uses frame memory 1405 as a work area in encoding or decoding. Additionally, the encoder/decoder machine 1407 outputs a timing signal to the memory control portion 1406, for example, at a timing of starting a process in each macroblock.

[00609] The video ES buffer 1408A temporarily stores a video stream generated by the encoding/decoding machine 1407, and provides the temporarily stored video stream to the multiplexer (MUX) 1412. The video ES buffer 1408B temporarily stores a demultiplexer (DMUX) provided video stream 1413, and provides the temporarily stored video stream to encoding/decoding machine 1407.

[00610] The audio ES buffer 1409A temporarily stores an audio stream generated by the audio encoder 1410, and provides the temporarily stored audio stream to the multiplexer (MUX) 1412. The audio ES buffer 1409B temporarily stores a stream demultiplexer (DMUX) provided audio stream 1413, and provides the temporarily stored audio stream to audio decoder 1411.

[00611] The audio encoder 1410, for example, digitally converts an audio signal that is input, for example, from connectivity 1321 (Figure 91) or similar, and encodes the converted audio signal in a predetermined method such as a method MPEG audio code or AudioCode number 3 (AC3). Audio encoder 1410 sequentially writes an audio stream that is encoded audio signal data to audio IO buffer 1409A. The audio decoder 1411 decodes an audio stream provided from the audio IE buffer 1409B to perform conversion to an analog signal, or the like, and provides the analog signal to, for example, connectivity 1321 (Figure 91) or the like as a reproduced audio signal.

[00612] The multiplexer (MUX) 1412 multiplexes the video stream and the audio stream. A method of multiplexing (that is, a bit stream format generated by multiplexing) is arbitrary. Furthermore, during multiplexing, the multiplexer (MUX) 1412 may add predetermined header information to the bit stream. In other words, the multiplexer (MUX) 1412 can convert a stream format by multiplexing. For example, the multiplexer (MUX) 1412 multiplexes the video stream and the audio stream so as to perform conversion into a transport stream which is bit stream with a broadcast format. Additionally, for example, the multiplexer (MUX) 1412 multiplexes the video stream and the audio stream to perform conversion into data (file data) with a recording file format.

[00613] The demultiplexer (DMUX) 1413 demultiplexes the bit stream in which a video stream and an audio stream are multiplexed, in a method corresponding to multiplexing by the multiplexer (MUX) 1412. In other words, the demultiplexer (DMUX) 1413 extracts a video stream and an audio stream from the bitstream that is read from the stream buffer 1414 (separates the video stream and the audio stream therefrom). That is, the demultiplexer (DMUX) 1413 can convert a stream format by demultiplexing (inverse conversion of the conversion at the multiplexer (MUX) 1412). For example, demultiplexer (DMUX) 1413 may acquire a transport stream that is provided by, say, connectivity 1321 or broadband modem 1333 (Figure 91), by stream buffer 1414, and demultiplexes the transport stream from so as to perform conversion on a video stream and an audio stream. Further, for example, demultiplexer (DMUX) 1413 may acquire file data that is read from various recording media, e.g., connectivity 1321 (Figure 91), via stream buffer 1414, and demultiplexes the transport stream of so as to perform conversion on a video stream and an audio stream.

[00614] Stream buffer 1414 temporarily stores a bit stream. For example, stream buffer 1414 temporarily stores a transport stream provided by multiplexer (MUX) 1412, and provides the stored transport stream to, for example, connectivity 1321 or broadband modem 1333 (Figure 91) to a predetermined timing, or on the basis of a request or similar from an external device.

[00615] In addition, for example, the stream buffer 1414 temporarily stores file data provided by the multiplexer (MUX) 1412, and provides the temporarily stored file data for, for example, connectivity 1321 (Figure 91) in order to recording the archive data onto various recording media at a predetermined timing, or on demand basis or the like from an external device.

[00616] Additionally, the stream buffer 1414 temporarily stores a transport stream that is acquired, for example, by connectivity 1321 or by the broadband modem 1333 (Figure 91), and provides the temporarily stored transport stream to the demultiplexer (DMUX ) 1413 at a predetermined timing, or on the basis of a request or similar from an external device.

[00617] In addition, the stream buffer 1414 temporarily stores file data that is read from various recording media in the connectivity 1321 (Figure 91) or the like, and provides the transport stream stores temporarily to the demultiplexer (DMUX) 1413 at a predetermined timing, or on the basis of a request or similar from an external device.

[00618] In the following, an example of an operation of the 1332 video processor having the configuration will be described. For example, a video signal that is input to video processor 1332 from connectivity 1321 (Figure 91) or similar is converted into digital image data in a predetermined scheme such as a Y/Cb/Cr 4:2:2 scheme by the video input processing portion 1401, and is sequentially written to the frame memory 1405. The digital image data is read at the first image enlargement/reduction portion 1402 or the second image enlargement/reduction portion 1403, and undergo format conversion and an enlargement or reduction process in a predetermined scheme such as a Y/Cb/Cr 4:2:0 scheme in order to be written to frame memory 1405 again. The image data is encoded by encoding/decoding machine 1407 and is then written to video IO buffer 1408A as a video stream.

[00619] Furthermore, an audio signal that is input to the video processor 1332 from the connectivity 1321 (Figure 91) or the like is encoded by the audio encoder 1410, and is written to the audio ES buffer 1409A as an audio stream .

[00620] The video stream from the video IO buffer 1408A and the audio stream from the audio IO buffer 1409A are read to the multiplexer (MUX) 1412 to be multiplexed and converted into a transport stream, file data, or similar. The transport stream generated by multiplexer (MUX) 1412 is temporarily stored in stream buffer 1414, and is then delivered to an external network, for example, by connectivity 1321 or by broadband modem 1333 (Figure 91). Furthermore, file data generated by multiplexer (MUX) 1412 is temporarily stored in stream buffer 1414, and is then output to, for example, connectivity 1321 (Fig. 91) in order to be recorded on various recording media.

[00621] Additionally, a transport stream that is input to the video processor 1332 from an external network, for example, via connectivity 1321 or broadband modem 1333 (Figure 91) is temporarily stored in the stream buffer 1414, and is then demultiplexed by demultiplexer (DMUX) 1413. Also, for example, file data that is read from various recording media, for example, in connectivity 1321 (Figure 91) and is input to video processor 1332 is temporarily stored in buffer of stream 1414, and are then demultiplexed by demultiplexer (DMUX) 1413. In other words, the transport stream or file data that is input to video processor 1332 is separated into a video stream and an audio stream by the demultiplexer (DMUX) 1413.

[00622] The audio stream is provided to the audio decoder 1411 by the audio IO buffer 1409B in order to be decoded and reproduced as an audio signal. Furthermore, the video stream that is written to the video ES buffer 1408B is then sequentially read by the encoding/decoding machine 1407 in order to be decoded and written to the frame memory 1405. The decoded image data undergoes a process enlargement or reduction in the second image enlargement/reduction portion 1403 in order to be written to the frame memory 1405. Additionally, the decoded image data is read to the video output processing portion 1404 in order to undergo format conversion in a predetermined scheme such as a Y/Cb/Cr 4:2:2 scheme and further undergo conversion to an analog signal, and thus a video signal is reproduced and produced.

[00623] In a case where the present technology is applied to the video processor 1332 having the configuration, the present description related to each embodiment described above can be applied to the encoding/decoding machine 1407. In other words, for example, the machine encoding/decoding device 1407 may have the function of the encoding device or the decoding device related to the first embodiment. Therefore, the video processor 1332 can achieve the same effects as the effects described with reference to Figures 6 to 13.

[00624] Furthermore, in the coding/decoding machine 1407, the present technology (that is, the function of the image coding device or the image decoding device related to each modality described above) can be realized through hardware such as a logic circuit, can be realized through software such as an embedded program, and can be realized by both of these.

Another example of Video Processor Configuration

[00625] Figure 93 illustrates another schematic configuration example of the video processor 1332 (Figure 91) to which the present technology is applied. In an example case of Fig. 93 , video processor 1332 has a function of encoding and decoding video data in a predetermined method.

[00626] More specifically, as illustrated in Figure 93, the video processor 1332 includes a control portion 1511, a display interface 1512, a display machine 1513, an image processing machine 1514 and an internal memory 1515. Additionally, video processor 1332 includes a codec machine 1516, a memory interface 1517, a multiplexer/demultiplexer (MUX DEMUX) 1518, a network interface 1519, and a video interface 1520.

[00627] The control portion 1511 controls an operation of each processing portion of the video processor 1332, such as the display interface 1512, the display machine 1513, the image processing machine 1514 and the codec machine 1516.

[00628] As illustrated in Figure 93, the control portion 1511 includes, for example, a main CPU 1531, a sub-CPU 1532 and a system controller 1533. The main CPU 1531 executes a program or the like to control an operation of each process portion of the video processor 1332. The main CPU 1531 generates a control signal according to the program or the like, and provides the control signal for each processing portion (that is, it controls an operation of each processing portion). ). Sub-CPU 1532 assists main CPU 1531. For example, sub-CPU 1532 executes a child process, a subroutine, or the like of a program executed by main CPU 1531. System controller 1533 controls the operations of the main CPU. Main CPU 1531 and sub-CPU 1532 designating a program that is to be executed by main CPU 1531 and sub-CPU 1532.

[00629] The display interface 1512 produces image data, for example, for connectivity 1321 (Figure 91) under the control of the control portion 1511. For example, the display interface 1512 converts digital image data into an analog signal and outputs the analog signal to a display device or the like from connectivity 1321 ( Fig. 91 ), or outputs the digital image data to the display device as is.

[00630] The display machine 1513 performs various conversion processes such as format conversion, size conversion and color series conversion into image data, so as to be satisfactory for a hardware specification of a display device or the like which displays an image, under the control of control portion 1511.

[00631] The image processing machine 1514 performs a predetermined image process such as a filter process to improve the image quality on the image data under the control of the control portion 1511.

[00632] The internal memory 1515 is a memory that is shared by the display machine 1513, the image processing machine 1514 and the codec machine 1516, and is provided in the video processor 1332. The internal memory 1515 is used to transmit and receiving data between, for example, display machine 1513, image processing machine 1514 and codec machine 1516. For example, internal memory 1515 stores data provided from display machine 1513, image processing machine 1514, or codec machine 1516, and provides the data to display machine 1513, image processing machine 1514, or codec machine 1516 as needed (e.g., in response to a request). The internal memory 1515 can be realized by any storage device, but is generally often used to store a small volume of data such as a block unit image data or a parameter, and is thus preferably implemented by a semiconductor memory having a relatively small capacity (for example, compared to external memory 1312), but has a high response speed, such as static random access memory (SRAM).

[00633] The codec machine 1516 performs a process relating to encoding or decoding image data. An encoding or decoding method supported by the codec machine 1516 is arbitrary, and the number of it can be one, and it can be many. For example, the codec machine 1516 can have codec functions of a plurality of encoding/decoding methods, and can perform encoding of image data or decoding of encoded data in a method selected from among the methods.

[00634] In the example illustrated in Fig. 93, the codec machine 1516 includes, for example, MPEG-2 Video 1541, AVC/H.264 1542, HEVC/H.265 1543, HEVC/H.265 (Gradable) 1544 , HEVC/H.265 (Multi-view) 1545 and MPEG-DASH 1551, as functional blocks of codec-related processes.

[00635] MPEG-2 Video 1541 is a functional block that encodes or decodes image data in MPEG-2 method. AVC/H.264 1542 is a functional block that encodes or decodes image data in the AVC method. HEVC/H.265 1543 is a functional block that encodes or decodes image data in the HEVC method. The HEVC/H.265 (Gradable) 1544 is a function block that scalably encodes or decodes image data in the HEVC method. HEVC/H.265 (Multi-view) 1545 is a function block that multi-view encodes or multi-view decodes image data in the HEVC method.

[00636] The MPEG-DASH 1551 is a functional block that transmits and receives image data in the MPEG Dynamic Adaptive Stream Transmission method via HTTP (MPEG-DASH). MPEG-DASH is a technique of performing streaming of a video using Hyper-Text Transfer Protocol (HTTP), it has one of features in which appropriate data is selected in the segment unit from a plurality of encoded data items that are prepared in advance and have resolutions or similar different from each other, and are transmitted. MPEG-DASH 1551 performs generation of a stream conforming to a standard, stream transmission control, or the like, and uses MPEG-2 Video 1541 described above, or HEVC/H.265 (Multiview) 1545 to encoding/decoding image data.

[00637] The memory interface 1517 is an interface for use in the external memory 1312. Data provided by the image processing machine 1514 or the codec machine 1516 is provided to the external memory 1312 by the memory interface 1517. In addition, data read of external memory 1312 are provided to video processor 1332 (image processing machine 1514 or codec machine 1516) via memory interface 1517.

[00638] The multiplexer/demultiplexer (MUX DEMUX) 1518 multiplexes or demultiplexes various data items relating to an image, such as bitstream encoded data, image data, and a video signal. A multiplexing and demultiplexing method is arbitrary. For example, during multiplexing, the multiplexer/demultiplexer (MUX DEMUX) 1518 can not only collect a plurality of data items into a single data item, but can also add predetermined or similar header information to the data. Furthermore, during demultiplexing, the multiplexer/demultiplexer (MUX DEMUX) 1518 can not only divide a single data item into a plurality of a plurality of data items, but also can add predetermined or similar header information to each data item. Divided. In other words, the multiplexer/demultiplexer (MUX DEMUX) 1518 can convert a data format by multiplexing and demultiplexing. For example, multiplexer/demultiplexer (MUX DEMUX) 1518 multiplexes a bit stream in order to perform conversion on a transport stream that is a bit stream with a broadcast format or data (file data) with a file format. recording. Of course, inverse conversion of this can be performed by demultiplexing.

[00639] The network interface 1519 is a dedicated interface, for example, for broadband modem 1333 or connectivity 1321 (Figure 91). Video interface 1520 is a dedicated interface, for example for connectivity 1321 or camera 1322 (Figure 91).

[00640] In the following, an example of an operation of the video processor 1332 will be described. For example, when a transport stream is received from an external network, for example via connectivity 1321 or broadband modem 1333 (Fig. 91), the transport stream is provided to the multiplexer/demultiplexer (MUX DEMUX) 1518 via the interface codec machine 1519 so as to be demultiplexed, and is then decoded by the codec machine 1516. Image data that is obtained by encoding in the codec machine 1516 undergoes a predetermined image processing, for example, by the image processing machine 1514 of to undergo predetermined conversion, and are then provided for, for example, connectivity 1321 (Figure 91) by display interface 1512, and an image thereof is displayed on a monitor. Further, for example, the image data obtained by coding in the codec machine 1516 is decoded again by the codec machine 1516 so as to be multiplexed by the multiplexer/demultiplexer (MUX DEMUX) 1518 and converted into file data, and is then produced for, for example, connectivity 1321 (Figure 91) by the video interface 1520 in order to be recorded on various recording media.

[00641] Additionally, for example, encoded data file data which is encoded picture data and is read from a recording medium (not illustrated) via connectivity 1321 (Figure 91) is provided to multiplexer/demultiplexer (MUX DEMUX) 1518 through the video interface 1520, and are then decoded by the codec machine 1516. The image data obtained by decoding in the codec machine 1516 undergoes a predetermined image process by the image processing machine 1514 so as to undergo predetermined conversion by the codec machine 1516. display 1513, and are then provided for, for example, connectivity 1321 (Figure 91) by display interface 1512, and an image thereof is displayed on the monitor. Further, for example, the image data obtained by decoding in the codec machine 1516 is encoded again by the codec machine 1516 in order to be multiplexed by the multiplexer/demultiplexer (MUX DEMUX) 1518 and converted into a transport stream, and they are then produced for, for example, connectivity 1321 or broadband modem 1333 (Figure 91) by network interface 1519 in order to be provided to other appliances (not shown).

[00642] Additionally, transmission and reception of image data or other data between the respective processing portions of the video processor 1332 are performed using, for example, the internal memory 1515 or the external memory 1312. Furthermore, the administration module power supply 1313 controls the provision of power to, for example, control portion 1511.

[00643] If the present technology is applied to the video processor 1332 having the configuration, the present technology related to each embodiment described above can be applied to the codec machine 1516. In other words, for example, the codec machine 1516 can include a functional block for realizing the coding device or the decoding device related to the first embodiment. Furthermore, for example, if the codec engine 1516 includes the functional block described above, the video processor 1332 can achieve the same effects as the effects described with reference to Figures 6 to 13.

[00644] Furthermore, in the codec machine 1516, the present technology (that is, the function of the image coding device or the image decoding device related to each modality described above) can be realized through hardware such as a logic circuit, can be performed by software such as an embedded program, and can be performed by both of these.

[00645] As mentioned above, the two exemplary configurations of the video processor 1332 have been described, but the video processor 1332 can have any configuration, and it can have different configurations of the two exemplary configurations. Furthermore, the video processor 1332 can be configured by a single semiconductor chip, and it can be configured by a plurality of semiconductor chips. For example, a three-dimensional stacked LSI in which a plurality of semiconductors are stacked can be used. Additionally, video processor 1332 may be implemented by a plurality of LSIs.

Appliance Application Examples

[00646] The video apparatus 1300 can be incorporated into various apparatus that process image data. For example, video apparatus 1300 may be incorporated in television apparatus 900 (Figure 84), mobile telephone 920 (Figure 85), recording/playback apparatus 940 (Figure 86), imaging apparatus 960 ( Figure 87), and similar. The video apparatus 1300 is incorporated in the apparatus, and thus the apparatus can achieve the same effects as the effects described with reference to Figures 6 to 13.

[00647] Furthermore, the video apparatus 1300 can be incorporated, for example, in the terminal apparatuses such as the personal computer 1004, the AV apparatus 1005, the tablet device 1006 and the mobile phone 1007 of the data transmission system 1000 of Fig. 88, the broadcasting station 1101 and the terminal apparatus 1102 of the data transmission system 1100 of Fig. 89, the imaging apparatus 1201 and the scalable coded data storage device 1202 of the imaging system 1200 of Fig. 90, and the like. The video apparatus 1300 is incorporated in the apparatus, and thus the apparatus can achieve the same effects as the effects described with reference to Figures 6 to 13.

[00648] Furthermore, even if only some of the configurations described above of the video apparatus 1300 include the video processor 1332, the configurations can be implemented as configurations to which the present technology is applied. For example, only video processor 1332 can be implemented as a video processor to which present technology is applied. Furthermore, for example, as described above, the processor, video module 1311, or the like indicated by the dotted line 1341 may be implemented as a processor, a module, or the like to which the present technology is applied. Additionally, a combination of the video module 1311, the external memory 1312, the power management module 1313 and the front end module 1314 can be implemented as the display unit 1361 to which the present technology is applied. Any configuration can achieve the same effects as the effects described with reference to Figures 6 to 13.

[00649] In other words, any configuration including the video processor 1332 can be incorporated into various devices that process image data in the same way as the video device 1300. For example, the video processor 1332, the processor indicated by the line dotted line 1341, video module 1311, or display unit 1361 may be incorporated into television set 900 (Figure 84), mobile telephone 920 (Figure 85), recording/playback apparatus 940 (Figure 86), image forming apparatus 960 (Figure 87), in the terminal apparatuses such as the personal computer 1004, the AV apparatus 1005, the tablet device 1006, and the mobile telephone 1007 of the data transmission system 1000 of Figure 88, the broadcasting station 1101 and the terminal apparatus 1102 of the data transmission system 1100 of Fig. 89, the imaging apparatus 1201 and the scalable coded data storage device 1202 of the imaging system 1200 of Fig. 90, and the like . Any of the configurations to which the present technology is applied are incorporated in the apparatus, and thus the apparatus can achieve the same effects as the effects described with reference to Figures 6 to 13 in the same manner as in the video apparatus 1300.

[00650] Furthermore, in the present specification, description has been made of an example in which various pieces of information such as conversion information, DR conversion information, and an approximate elbow index are multiplexed into encoded data, and are transmitted from one encoding side to one decoding side. However, a method of transmitting the information is not limited to this example. For example, the information can be transmitted or recorded as separate data associated with encoded data without being multiplexed into the encoded data. Here, the term "associated" indicates that a picture (which may be a part of the picture, such as a slice or a block) included in the bit stream is made to be linked with information corresponding to the picture during decoding. In other words, the information can be transmitted on a different transmission path than the encoded data. Furthermore, the information may be recorded on a recording medium (or a different recording area of the same recording medium) different from that of the encoded data. Additionally, the encoded information and data may be associated with each other in any unit such as a plurality of frames, a single frame, or a portion of a frame.

[00651] Furthermore, in the present specification, the system indicates a set of a plurality of constituent elements (devices, modules (components), or the like), and it does not matter whether or not all the constituent elements are located on the same roof. Therefore, a plurality of devices that are stored in separate covers and are connected to each other by a network, a single device in which a plurality of modules are stored in a single cover, are all one system.

[00652] The effects described in the present specification are only an example and are not limited, and there may be other effects.

[00653] Furthermore, embodiments of the present description are not limited to the above-described embodiments, and may have various modifications within the scope without departing from the spirit of the present description.

[00654] For example, the present description may have a cloud computing configuration in which a single function is distributed to a plurality of devices over a network and are processed cooperatively with each other.

[00655] Additionally, each step described in the previous flowchart can be performed by a single device, and can also be performed by a plurality of devices in a distribution manner.

[00656] Furthermore, in a case where a plurality of processes are included in a single step, the plurality of processes included in a single step can be performed by a single device, and can also be performed by a plurality of devices in a manner of distribution.

[00657] The present description can have the following configurations. (1) A decoding device including: circuitry configured to receive coded data and conversion information, the coded data belonging to a picture having luminance in a first dynamic range, and the conversion information belonging to a dynamic range conversion of luminance image of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function. (2) The decoding device according to the above (1), in which the conversion uses an elbow. (3) The decoding device according to the above (1) or (2), wherein the conversion uses the knee function to map the dynamic range of the image luminance from the first dynamic range to the second dynamic range, and the function knee is defined by the elbow. (4) The decoding device according to any of the foregoing (1) to (3), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee function objective in the first dynamic range and post-conversion information indicating a luminance range in the second dynamic range that corresponds to the luminance range that is the knee function target in the first dynamic range. (5) The decoding device according to any of the foregoing (1) to (4), wherein the pre-conversion information indicates the luminance range that is converted by knee function to the same conversion ratio as a conversion range of the first dynamic range. (6) The decoding device according to any of the above (1) to (5), wherein the conversion uses the knee function that is defined by a plurality of elbows. (7) The decoding device according to any of the above (1) to (6), wherein the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. (8) The decoding device according to any of the above (1) to (7), wherein the conversion uses the knee function mapping the dynamic range of the image luminance from the first dynamic range to the second dynamic range, and a plurality of adjacent segments of the first luminance dynamic range is mapped to a corresponding plurality of adjacent segments of the second luminance dynamic range based on boundaries between adjacent segments defined by a plurality of elbows. (9) The decoding device according to any of the above (1) to (8), wherein the conversion uses the knee function mapping the dynamic range of the image luminance from the first dynamic range to the second dynamic range to a first ratio conversion ratio for a point defined by the elbow and a second conversion ratio for the point defined by the elbow. (10) The decoding device according to any of the above (1) to (9), wherein the knee function is specified by a SEI message. (11) The decoding device according to any of the above (1) to (10), wherein the SEI message includes an establishment of a knee_function_id. (12) A decoding method of making a decoding device perform: receiving coded data and conversion information, the coded data belonging to a picture having luminance in a first dynamic range and the conversion information belonging to a dynamic range conversion of image luminance of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function. (13) The decoding method according to the above (12), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee function objective in the first dynamic range and post-conversion information conversion indicating a luminance range in the second dynamic range that corresponds to the luminance range that is the knee function target in the first dynamic range. (14) The decoding method according to the above (12) or (13), wherein the pre-conversion information indicates the luminance gamma which is converted through knee function to the same conversion ratio as a gamma first dynamic range conversion. (15) The decoding method according to any of the above (12) to (14), wherein the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. (16) The decoding method according to any of the above (12) to (15), wherein the conversion uses the knee function by mapping the dynamic range of the image luminance from the first dynamic range to the second dynamic range to a first relation conversion ratio for a point defined by the elbow and a second conversion ratio for the point defined by the elbow. (17) An encoding device including: circuitry configured to establish conversion information pertaining to a dynamic range conversion of a luminance of an image of a first dynamic range into a second dynamic range; and encoding the image having luminance in the first dynamic range to generate encoded data, wherein the conversion uses a knee function. (18) The coding device according to the above (17), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee function objective in the first dynamic range and post-conversion information conversion indicating a luminance range in the second dynamic range that corresponds to the luminance range that is the knee function target in the first dynamic range. (19) The coding device according to the above (17) or (18), wherein the pre-conversion information indicates the luminance range which is converted through knee function to the same conversion ratio as a gamma first dynamic range conversion. (20) The encoding device according to any of the above (17) to (19), wherein the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. (21) The coding device according to any of the foregoing (17) to (20), wherein the conversion uses the knee function mapping the dynamic range of the image luminance of the first dynamic range into the second dynamic range to a first relation conversion ratio for a point defined by the elbow and a second conversion ratio for the point defined by the elbow. (22) A non-transient computer-readable medium having stored thereon coded data and conversion information, the coded data belonging to an image having luminance in a first dynamic range and the conversion information belonging to a dynamic range conversion of the luminance of the image of the first dynamic range into a second dynamic range, wherein a decoding device decodes encoded data, generates the image based on the decoded data, and converts the dynamic range based on the conversion information including an elbow. (23) The non-transient computer-readable medium according to the above (22), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee function objective in the first dynamic range and information of post-conversion indicating a luminance range in the second dynamic range that corresponds to the luminance range that is the knee function objective in the first dynamic range. (24) The non-transient computer-readable medium according to the above (22) or (23), wherein the pre-conversion information indicates the range of luminance that is converted via knee function at the same conversion ratio as a gamma conversion of the first dynamic range. (25) The non-transitory computer-readable medium according to any of the above (22) to (24), wherein the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. (26) The non-transient computer-readable medium according to any of the above (22) to (25), wherein the conversion uses the knee function mapping the dynamic range of the image luminance from the first dynamic range to the second dynamic range to a first conversion ratio for a point defined by the elbow and a second conversion ratio for the point defined by the elbow. (27) A decoding device including an extraction unit that extracts encoded data and conversion information from an encoded stream including the encoded data of a first image which is an image having luminance in a first dynamic range and conversion information relating to the converting a dynamic range of the image's luminance from the first dynamic range into a second dynamic range; and a decoding unit that decodes the encoded data extracted by the extraction unit to generate the first image. (28) The decoding device according to the above (27), further including a conversion unit that converts the first image that is generated by the decoding unit into a second image that is the image having luminance in the second dynamic range at the base conversion information by the extraction unit. (29) The decoding device according to the above (27) or (28), wherein the conversion is performed by knee converting the luminance of the first image. (30) The decoding device according to any one of the foregoing (27) to (29), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee conversion target in the first range dynamics and post-conversion information indicating a luminance range in the second dynamic range, corresponding to the range. (31) The decoding device according to any one of the foregoing (27) to (30), wherein the pre-conversion information indicates a luminance range which is knee-converted at the same conversion ratio as a conversion gamma of the first dynamic range, and wherein the conversion information includes a plurality of pairs of the pre-conversion information and the post-conversion information. (32) The decoding device according to any one of the above (27) to (31), further including a selection unit that selects a predetermined number of pairs from among the plurality of pairs included in the conversion information that is extracted by the unit extraction, in an order in which the pairs are included in the conversion information. (33) The decoding device according to any one of the foregoing (27) to (31), further including a selection unit that selects a predetermined number of pairs from among the plurality of pairs included in the conversion information in the information base of priority indicating an order in which a priority of the pair is highest in which the extraction unit extracts the priority information included in the encoded stream. (34) The decoding device according to any one of the above (27) to (33), further including a transmission unit that transmits the predetermined number of pairs selected by the selection unit. (35) The decoding device according to any one of the above (27) to (34), wherein the conversion information includes at least one of a maximum luminance value of the first picture and a maximum luminance value of the second picture . (36) The decoding device according to any one of the foregoing (27) to (35) wherein the conversion information includes one of an expected brightness value of a display unit displaying at least the first image and a value expected brightness of a display unit displaying the second image. (37) A decoding method of having a decoding device perform extracting coded data and conversion information from a coded stream including the coded data of a first picture which is a picture having luminance in a first dynamic range and the conversion information which is information relating to the conversion of a dynamic range of image luminance from the first dynamic range to a second dynamic range; and decoding the encoded data to generate the first image. (38) An encoding device including a setting unit which sets conversion information which is information relating to converting a luminance dynamic range of an image from a first dynamic range to a second dynamic range; a coding unit that encodes a first image which is the image having luminance in the first dynamic range to generate encoded data; and a transmission unit that transmits an encoded stream including the conversion information established by the setting unit and the first picture encoded data generated by the encoding unit. (39) The coding device according to the above (38), wherein the conversion is performed by knee-converting the luminance of the first image. (40) The coding device according to the above (38) or (39), wherein the conversion information includes pre-conversion information indicating a luminance range that is a knee conversion target in the first dynamic range and post-conversion information indicating a range of luminance in the second dynamic range, corresponding to the range. (41) The coding device according to any one of the foregoing (38) to (40), wherein the pre-conversion information indicates a luminance range which is knee-converted at the same conversion ratio as a conversion range of the first dynamic range, and wherein the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. (42) The encoding device according to any one of the above (38) to (41), wherein the conversion information includes the plurality of pairs of pre-conversion information and post-conversion information in an order in which a priority is higher. (43) The coding device according to any one of the above (38) to (42), wherein the transmission unit transmits priority information indicating an order in which a priority of the pair is highest. (44) The coding device according to any one of the above (38) to (43), wherein the conversion information includes at least one of a maximum luminance value of the first picture and a maximum luminance value of the second picture . (45) The encoding device according to any one of the foregoing (38) to (44), wherein the conversion information includes one of an expected brightness value of a display unit displaying at least the first image and a expected brightness value of a display unit that displays the second image. (46) An encoding method of making an encoding device perform downscaling information which is information relating to converting a luminance dynamic range of an image from a first dynamic range to a second dynamic range; encoding a first image which is the image having luminance in the first dynamic range to generate encoded data; and transmitting an encoded stream including the established conversion information and the generated encoded data of the first image.

[00658] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors so far as they are within the scope of the appended claims or the equivalents thereof. List of Reference Signals Encoding device Establishment unit Encoding unit Transmission unit Conversion unit Decoding device Extraction unit Decoding unit Conversion unit Encoding device Establishment unit Encoding unit Decoding device Extraction unit Decoding unit Conversion unit Decoding system Decoding device Display device Selecting unit Transmitting unit

Claims (14)

1. Decoding device (50, 90, 111), characterized in that it comprises: circuitry configured to: receive encoded data and conversion information, the encoded data belonging to an image having luminance in a first dynamic range, and the information conversion pertaining to a dynamic range conversion of the image luminance of the first dynamic range into a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function, and the conversion information includes conversion persistence information that indicates whether or not the conversion information is applied to a plurality of continuous images. 2. Decoding device (50, 90, 111) according to claim 1, characterized in that the conversion uses a knee. 3. Decoding device (50, 90, 111) according to claim 2, characterized in that the conversion uses the knee function to map the dynamic range of the luminance of the image of the first dynamic range into the second dynamic range, and the Knee function is defined by the knee. 4. Decoding device (50, 90, 111) according to claim 3, characterized in that the conversion information includes pre-conversion information indicating a luminance range that is a knee function objective in the first dynamic range and post-conversion information indicating a luminance range in the second dynamic range that corresponds to the luminance range that is the knee function target in the first dynamic range. 5. Decoding device (50, 90, 111) according to claim 4, characterized in that the pre-conversion information indicates the luminance range that is converted through the knee function to the same conversion ratio as a conversion range of the first dynamic range. 6. Decoding device (50, 90, 111) according to claim 1, characterized in that the conversion uses the knee function that is defined by a plurality of knees. 7. Decoding device (50, 90, 111) according to claim 6, characterized in that the conversion information includes a plurality of pairs of pre-conversion information and post-conversion information. 8. Decoding device (50, 90, 111) according to claim 1, characterized in that the conversion uses the knee function mapping the dynamic range of the luminance of the image of the first dynamic range into the second dynamic range, and a plurality of adjacent segments of the first luminance dynamic range is mapped to a corresponding plurality of adjacent segments of the second luminance dynamic range based on boundaries between adjacent segments defined by a plurality of knees. 9. Decoding device (50, 90, 111) according to claim 3, characterized in that the conversion uses the knee function mapping the dynamic range of the luminance of the image of the first dynamic range into the second dynamic range to a first ratio conversion ratio for a knee point and a second knee point conversion ratio. 10. Decoding device (50, 90, 111) according to claim 1, characterized in that the knee function is specified by an SEI message. 11. Decoding device (50, 90, 111) according to claim 10, characterized in that the SEI message includes an establishment of a knee_function_id. 12. Decoding method, characterized in that it is for making a decoding device (50, 90, 111) perform: receiving coded data and conversion information, the coded data belonging to a picture having luminance in a first dynamic range and the conversion information pertaining to a dynamic range conversion of the image's luminance from the first dynamic range to a second dynamic range; and decoding the received encoded data to generate the image, wherein the conversion uses a knee function, and the conversion information includes persistence information that indicates whether or not the conversion information is applied to a plurality of continuous images. 13. Coding device (10, 70), characterized in that it comprises: circuitry configured to: establish conversion information pertaining to a dynamic range conversion of an image luminance of a first dynamic range into a second dynamic range ; and encoding the image having luminance in the first dynamic range to generate encoded data, wherein the conversion uses a knee function. 14. Non-transient computer-readable media characterized by the fact that it has computer-readable instructions stored therein that, when read by a computer, cause the computer to execute the method as defined in claim 12.