JP2019118151A - Transmission device, transmission method, reception device, and reception method - Google Patents

Abstract

To prevent the occurrence of image disturbance on a reception side in a case where plural types of transmission video data of different dynamic ranges are mixed and transmitted.SOLUTION: A transmission device transmits a container of a predetermined format containing a first component stream having, as component data, transmission video data obtained by switching plural types of transmission video data and a predetermined number of second component streams having other component data. Dynamic range information of component data belonging to each component stream is inserted to each component stream.SELECTED DRAWING: Figure 2

Description

  The present technology relates to a transmitting device, a transmitting method, a receiving device and a receiving method, and more particularly to a transmitting device that transmits another stream having graphics data, subtitle data, etc. together with a video stream.

  Usually, transmission video data of a dynamic range and transmission video data of a high dynamic range may be mixed and transmitted. Hereinafter, the dynamic range is usually referred to as "SDR" and the high dynamic range is referred to as "HDR" as appropriate. In this case, the normal dynamic range transmission video data is obtained by applying the normal dynamic range photoelectric conversion to the normal dynamic range video data, and the high dynamic range transmission video data has a high dynamic range to the high dynamic range video data. It is obtained by applying photoelectric conversion. For example, Non-Patent Document 1 describes a HDR photoelectric conversion characteristic (new gamma characteristic) including a compatible region with a conventional photoelectric conversion characteristic (gamma characteristic) in consideration of reception by a conventional receiver.

  The switching of the transmission video data of the normal dynamic range and the transmission video data of the high dynamic range may occur, for example, at the timing of program switching or CM insertion. When such switching is performed, it is necessary to switch the electro-optical conversion characteristics on the receiving side, but image distortion may occur due to the switching, or display mute may be performed to hide the image disturbance.

  As an example in which the distortion is noticeable, there is a graphic display by so-called "d-button" operation, which exists as one of broadcast services. In this case, graphics are superimposed across programs and CMs, but when the image by the video data displayed in the small window is switched from SDR to HDR or HDR to SDR, the color and brightness in the graphics display are It happens to change.

Tim Borer, “Non-Linear Opto-Electrical Transfer Functions for High Dynamic Range Television”, Research & Development White Paper WHP 283, July 2014

  An object of the present technology is to prevent occurrence of distortion on the receiving side well in the case where a plurality of types of transmission video data having different dynamic ranges are mixed and transmitted.

The concept of this technology is
A container of a predetermined format including a predetermined number of second component streams having other component data is transmitted together with the first component stream having transmission video data obtained by switching plural types of transmission video data as component data The transmitter to
A transmitting apparatus is provided with an information insertion unit that inserts dynamic range information of component data of each component stream into each of the component streams.

  In the present technology, a predetermined number of second component streams having other component data together with a first component stream having transmission video data obtained by switching transmission video data of a plurality of types by the transmission unit as component data A container of a predetermined format is sent, including For example, the predetermined number of second component streams may be configured to include a data broadcast stream and / or a subtitle stream. The information insertion unit inserts dynamic range information of component data of each component stream into each component stream.

  As described above, in the present technology, dynamic range information of component data of each component stream is inserted into each component stream. Therefore, on the receiving side, it is possible to obtain output data by combining each component data after performing luminance mapping processing to match display performance based on the respective dynamic range information.

  In this case, since the characteristics of electro-optical conversion to be applied to the output data can be fixed, it is possible to prevent the occurrence of distortion due to the switching of the electro-optical conversion characteristics. For example, when graphics are displayed together with an image by video data, even if the image by video data is switched from SDR to HDR or from HDR to SDR, there is no change in color or brightness in graphics display. Further, in this case, since the luminance mapping process is performed on each component data so as to match the display performance, it is possible to always display the display by each component data in an appropriate luminance state.

  In the present technology, for example, the information insertion unit may further insert color gamut information of component data of each component stream into each component stream. In this case, it is possible to obtain output data by combining each component data after performing color gamut conversion so as to match display performance based on the respective color gamut information on the receiving side, so that display by each component data is always performed. It becomes possible to display in an appropriate color state.

  Further, in the present technology, for example, identification information indicating the type of transmission video data possessed by the first component stream included in the container is switched from the timing earlier by a predetermined amount of time than the switching timing to the layer of the container. The information insertion unit may further be inserted to indicate the type of later transmission video data. In this case, on the reception side, it becomes possible to switch the type of transmission video data from timing earlier than the switching timing by a predetermined amount of time or more and to recognize the type of transmission video data after switching.

Also, the other concept of this technology is
Receiving a container of a predetermined format including a predetermined number of second component streams having other component data, together with a first component stream having transmission video data obtained by switching between plural types of transmission video data as component data Equipped with a receiver to
Dynamic range information of the component data of each component stream is inserted in each of the above component streams,
The system further comprises a processing unit that decodes each of the component streams to obtain a plurality of component data and combines the obtained plurality of component data to obtain output data.
The above processing unit
The present invention is provided in a receiving apparatus for obtaining the output data by combining each component data described above with luminance mapping processing so as to match display performance based on the respective dynamic range information.

  In the present technology, a predetermined number of second component streams having other component data as well as a first component stream having transmission video data obtained by switching a plurality of types of transmission video data as component data by the reception unit A container of a predetermined format is received, including Dynamic range information of component data of each component stream is inserted in each component stream.

  The processing unit decodes each component stream to obtain a plurality of component data, and combines the plurality of component data to obtain output data. In the processing unit, each component data is subjected to luminance mapping processing so as to match display performance based on the respective dynamic range information, and then synthesized to obtain output data.

  As described above, in the present technology, each component data is subjected to luminance mapping processing so as to match display performance based on the respective dynamic range information, and then combined to obtain output data. Therefore, it is possible to fix the characteristics of electro-optical conversion to be applied to the output data, and to prevent the occurrence of distortion due to the switching of the electro-optical conversion characteristics. In addition, it is possible to always display the display by each component data in an appropriate luminance state.

  Further, in the present technology, for example, color gamut information of component data possessed by each component stream is further inserted into each component stream, and the processing unit displays each component data based on the respective color gamut information. It may be combined to obtain output data after being subjected to gamut conversion processing to match performance. In this case, the display by each component data can be always displayed in an appropriate color state.

  According to the present technology, in the case where a plurality of types of transmission video data having different dynamic ranges are mixed and transmitted, the occurrence of distortion on the receiving side can be favorably prevented. The effects described in the present specification are merely examples and are not limited, and additional effects may be present.

It is a block diagram showing an example of composition of a transmitting and receiving system as an embodiment. It is a block diagram which shows the structural example of a service transmission system. It is a figure for demonstrating a photoelectric conversion characteristic. It is a figure for demonstrating the relationship between the switching timing of transmission video data, and the insertion timing of the identification information for identifying the transmission video data after replacement | exchange. It is a figure which shows the structural example of a HDR * video descriptor. It is a figure which shows the content of the main information in the structural example of a HDR * video descriptor. It is a figure which shows the structural example of a HDR * subtitle * descriptor. It is a figure which shows the structural example of the transport stream of MPEG-2 TS. It is a figure which shows the structural example of the transport stream of MMT. It is a block diagram which shows the structural example of a service receiver. It is a figure which shows the outline | summary of the luminance mapping process in, when display performance is HDR. It is a block diagram showing an example of composition of a picture composition processing part in case display performance is HDR and a wide color gamut. It is a figure for demonstrating the structure of a brightness | luminance mapping part. It is a figure for demonstrating the brightness | luminance mapping part in case display performance is HDR and input transmission video data is SDR transmission video data. It is a figure for demonstrating a brightness | luminance mapping part in case display performance is HDR and input transmission video data is HDR transmission video data. It is a figure for demonstrating a brightness | luminance mapping part in case display performance is SDR and input transmission video data is HDR transmission video data. It is a figure which shows the example of the graphics display by "d button" operation which exists as one of broadcast services.

Hereinafter, modes for carrying out the invention (hereinafter referred to as “embodiments”) will be described. The description will be made in the following order.
1. Embodiment 2. Modified example

<1. Embodiment>
[Example configuration of transmission / reception system]
FIG. 1 shows a configuration example of a transmission / reception system 10 as an embodiment. The transmission / reception system 10 is configured of a service transmission system 100 and a service receiver 200. The service transmission system 100 generates a transport stream (multiplexed stream) of MPEG-2 TS (MPEG-2 Transport Stream) or MMT (MPEG Media Transport) as a container, and this transport stream is broadcast waves or nets. Put it in a packet and send it.

  In this transport stream, a first component stream (video stream) having transmission video data obtained by switching transmission video data of a plurality of types as component data, and a predetermined number of second having another component data Component stream of The predetermined number of second component streams include, for example, data service streams (data broadcast streams) and / or subtitle streams, and in this embodiment, data broadcast streams and subtitle streams are included. The data service stream has, for example, graphics data, image data, etc. as component data. The subtitle stream has subtitle data as component data.

  Dynamic range information of component data of each component stream is inserted into each component stream. Also, color gamut information of component data possessed by each component stream is inserted into each component stream. Also, identification information indicating the type of transmission video data possessed by the first component stream included in the transport stream is the type of transmission video data after switching from a timing earlier than the switching timing by a predetermined time amount or more. Inserted as shown.

  The service receiver 200 receives the above-described transport stream (a transport stream of MPEG-2 TS or MMT) transmitted from the service transmission system 100. The service receiver 200 decodes each component stream to obtain a plurality of component data, and combines the obtained plurality of component data to obtain output data.

  In this case, each component data is subjected to luminance mapping processing so as to match display performance based on the respective dynamic range information and then synthesized to obtain output data. Furthermore, in this embodiment, each component data is subjected to color gamut conversion processing so as to match display performance based on the respective color gamut information, and then combined to obtain output data.

  The service receiver 200 performs electro-optical conversion (electro-optical conversion characteristics are fixed) on the output data to obtain display image data, and displays an image based on the display image data.

"Configuration example of service transmission system"
FIG. 2 shows a configuration example of the service transmission system 100. The service transmission system 100 includes a control unit 101, a video encoder 102, a data service encoder 103, a still image encoder 104, a subtitle encoder 105, a container encoder 106, and a transmission unit 107.

  The control unit 101 includes a CPU (Central Processing Unit), and controls the operation of each unit of the service transmission system 100 based on a control program. The video encoder 102 performs coding such as MPEG4-AVC or HEVC on input transmission video data to obtain coded video data, and a video stream as a component stream including the coded video data. Generate VS. The video stream VS includes transmission video data as component data.

  The input transmission video data is obtained by switching between a plurality of types of transmission video data. The plurality of types of transmission video data include, for example, transmission video data of a normal dynamic range and transmission video data of a high dynamic range. Here, the transmission video data of the normal dynamic range is obtained by applying the normal dynamic range photoelectric conversion to the normal dynamic range video data. In addition, high dynamic range transmission video data is obtained by applying high dynamic range photoelectric conversion to high dynamic range video data.

  FIG. 3 shows an example of so-called photoelectric conversion characteristics representing non-linear luminance code value characteristics, which are used when converting the luminance of linear light in physical space into a transmission space of a finite band. In this figure, the horizontal axis indicates the input luminance level, and the vertical axis indicates the transmission code value. Curve a shows an example of SDR photoelectric conversion characteristics applied to normal dynamic range video data having an input luminance level of 0 to 100%. A curve b1 indicates an example of HDR photoelectric conversion characteristics applied to high dynamic range video data having an input luminance level of 0 to N * 100% (an example compatible with SDR photoelectric conversion characteristics). In the case of this example, the input luminance level up to the compatibility limit matches the SDR photoelectric conversion characteristic. When the input luminance level is at the compatibility limit value, the transmission code value is at the compatibility level.

  A curve b2 indicates an example of the HDR photoelectric conversion characteristic applied to high dynamic range video data having an input luminance level of 0 to N * 100% (an example having no compatibility with the SDR photoelectric conversion characteristic). Furthermore, a curve b3 indicates an example of the HDR photoelectric conversion characteristic applied to high dynamic range video data with an input luminance level of 0 to M * 100% (an example having no compatibility with the SDR photoelectric conversion characteristic). Here, N and M each are a number larger than 1, and M <N. Although M <N in this example, the relationship between the maximum brightness of b2 and b3 may be MMN, including the general case.

  Returning to FIG. 2, the video encoder 102 receives dynamic range information and color gamut information of the input transmission video data. The video encoder 102 inserts this dynamic range information and gamut information into the video stream VS. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data.

  At this time, the video encoder 102 includes information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic possessed by the transmission video data in the region of VUI (video usability information) of the SPS NAL unit of the access unit (AU), Meta information such as color gamut information of transmission video data and information indicating a reference level is inserted. In addition, the video encoder 102 also includes meta information such as information (transfer function) indicating the electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic possessed by the transmission video data in the “SEIs” portion of the access unit (AU), and reference level information. Insert a SEI message with a (SEI message).

  Here, the reason that the information indicating the electro-optical conversion characteristic is added to the SEI message is that SPS NAL is compatible with the SDR photoelectric conversion characteristic when the HDR photoelectric conversion characteristic is compatible with the SDR photoelectric conversion characteristic even if the transmission video data is HDR transmission video data. Since the information indicating the electro-optical conversion characteristic (gamma characteristic) corresponding to the SDR photoelectric conversion characteristic is inserted in the VUI of the unit so that the conventional SDR compatible receiver can be identified, the video received by the HDR compatible receiver is HDR In order to be able to identify that it is, it is because the information which shows the electro-optical conversion characteristic corresponding to a HDR photoelectric conversion characteristic in places other than VUI is needed.

  In addition, when the transmission video data V1 is SDR transmission video data, the SEI message includes information on the reference level in the VUI of the SPS NAL unit with the electro-optical conversion characteristic (gamma characteristic) corresponding to the SDR photoelectric conversion characteristic. This is because the information shown is inserted, but there is no specification for inserting a reference level.

  In this case, for example, “BT. 709-5 Transfer Function (SDR)”, “10 bit BT. 2020 Transfer Function (SDR)”, “SMPTE 2084 Transfer Function (HDR 1)” according to information (transfer function) indicating the electro-optical conversion characteristic. The electro-optical conversion characteristics such as “HDR (HDR2)” are shown. Note that “HDR (HDR2)” is not a characteristic that supports “Human Visual System”, but is a conversion characteristic that partially has the same characteristics as the conventional gamma characteristic. The color gamut information indicates a color gamut such as "BT. 709-5", "BT. 2020", or "SMPTE 428 or XYZ".

  The still picture encoder 104 subjects the input image data to, for example, JPEG coding to obtain coded video data. Dynamic range information and color gamut information of image data are input to the still image encoder 104. The still picture encoder 104 inserts this dynamic range information and color gamut information into the encoded data. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the image data.

  The still image encoder 104, for information (transfer function) indicating the electro-optical conversion characteristic, for example, the value of the gamma tag (Gamma tag) defined by the Exif (Exchangeable image file format) standard defined by the JPEG standard. Value) is used. Currently, "16 (Gamma = BT. 709-5 Transfer Function (SDR))" is defined, but other values are "10 bit BT. 2020 Transfer Function (SDR)", "SMPTE 2084 Transfer Function (HDR 1) "HDR (HDR2)" etc. are defined and used.

  The still picture encoder 104 uses, for example, the value (Value) of a color space tag (ColorSpace tag) defined by the Exif standard defined by the JPEG standard, for color gamut information. Currently, “1 (sRGB = BT.709-5)” is defined, but “BT.2020”, “SMPTE 428 or XYZ”, etc. are defined and used as other values.

  The data service encoder 103 performs encoding processing on input graphics data and further encoded data input from the still picture encoder 104 to generate a data service stream DS as a component stream. The data service stream DS includes image data and graphics data as component data.

  The data service encoder 103 receives dynamic range information and color gamut information of graphics data. The data service encoder 103 inserts this dynamic range information and color gamut information into the data service stream DS. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the graphics data.

  The data service encoder 103 extends and defines, for example, dynamic range information “D_range” as information (transfer function) indicating an electro-optical conversion characteristic, “BT. 709-5 Transfer Function (SDR)”, “10 bit BT. 2020 They indicate Transfer Function (SDR), SMPTE 2084 Transfer Function (HDR1), and HDR (HDR2). Also, with respect to color gamut information, the data service encoder 103 uses, for example, the item “gfx.color_management.mode” to “BT.709-5”, “BT.2020”, “SMPTE 428 or XYZ”, etc. Indicates the color gamut of

  The subtitle encoder 105 subjects the input subtitle data to encoding processing to generate a subtitle stream SS as a component stream. Subtitle data is included in the subtitle stream SS as component data. Although the detailed description is omitted, the subtitle stream SS includes subtitle text information such as TTML (Timed Text Markup Language) or subtitle bitmap data.

  The subtitle encoder 105 receives dynamic range information and color gamut information of subtitle data. The subtitle encoder 105 inserts this dynamic range information and color gamut information into the subtitle stream SS.

  When the subtitle stream SS includes TTML as subtitle text information, the subtitle encoder 105 uses, for example, an element of metadata (metadata) present in the header of the TTML structure to identify a color gamut related to subtitle data. Whether to insert information and dynamic range information, or to insert color gamut identification information and dynamic range information related to subtitle data using elements of a styling extension (styling extension) present in the header of the TTML structure Alternatively, a segment including color gamut identification information and dynamic range information related to subtitle data is inserted into the subtitle stream SS.

  On the other hand, when the subtitle stream SS includes subtitle bitmap data, the subtitle encoder 105 inserts, for example, a segment including color gamut identification information and dynamic range information related to the subtitle data into the subtitle stream SS.

  In this case, for example, “BT. 709-5 Transfer Function (SDR)”, “10 bit BT. 2020 Transfer Function (SDR)”, “SMPTE 2084 Transfer Function (HDR 1)” according to information (transfer function) indicating the electro-optical conversion characteristic. The electro-optical conversion characteristics such as “HDR (HDR2)” are shown. Note that "HDR (HDR2)" is not a PQ curve but a so-called hybrid gamma. The color gamut information indicates a color gamut such as "BT. 709-5", "BT. 2020", or "SMPTE 428 or XYZ".

  The container encoder 106 is a transport stream (MPEG-2 TS or the like) including the video stream VS generated by the video encoder 102, the data service stream DS generated by the data service encoder 103, and the subtitle stream SS generated by the subtitle encoder 105. Generate MMT Transport Stream). The transmitting unit 107 transmits the transport stream on broadcast waves or net packets and transmits the transport stream to the service receiver 200.

  At this time, the container encoder 106 causes the transport stream to carry identification information indicating the type of transmission video data possessed by the video stream VS contained in the transport stream by a predetermined time or more before the switching timing of the type of transmission video data. It inserts so that the kind of transmission video data after switching from timing may be shown. By managing the insertion of the identification information in this manner, the receiving side is notified of the dynamic switching of the transmission video data.

FIG. 4 shows identifications for identifying switching timing Sn (S0, S1, S2,...) Of SDR transmission video data (SDR service) and HDR transmission video data (HDR service) and transmission video data after switching. The relation of the information insertion timing Tn (T0, T1, T2,...) Is shown. The timing Tn is set to be earlier than the timing Sn by at least t (predetermined amount of time) so as to satisfy the following equation (1). In addition, the example of illustration has shown the case where it is Sn-Tn = t (however, t is a positive value).
Sn-Tn t t (1)

  The container encoder 109 inserts an HDR video descriptor (HDR_vido_descriptor) that is newly defined, for example, in correspondence to the video stream VS. For example, when the transport stream is a transport stream of MPEG-2 TS, this descriptor is subordinate to a program map table (PMT: Program Map Table) or an event information table (EIT: Event Information Table) Is inserted under In addition, when the transport stream is an MMT transport stream, this descriptor is inserted under MP table (MPT: MMT Package Table) or under event information table (EIT: Event Information Table). Ru.

  FIG. 5 shows a structural example (Syntax) of the HDR video descriptor, and FIG. 6 shows contents (Semantics) of main information in the structural example. An 8-bit field of "descriptor_tag" indicates the type of descriptor, and here indicates that it is an HDR video descriptor. The 8-bit field of “descriptor_length” indicates the length (size) of the descriptor, and indicates the number of subsequent bytes as the length of the descriptor.

  The 1-bit flag information of “HDR_SDR_flag” indicates whether the target stream is an HDR stream or an SDR stream. "1" indicates that this is an HDR stream, and "0" indicates that this is an SDR stream. The 1-bit flag information of “video_characteristics_info_flag” indicates whether or not there is characteristic information. "1" indicates that there is characteristic information, and "0" indicates that there is no characteristic information.

  When “video_characteristics_info_flag” is “1”, 8-bit fields “transferfunction”, “color_space” and “referencelevel” are present. The 8-bit field of "transferfunction" indicates an electro-optical conversion characteristic (EOTF characteristic). That is, this field shows an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data. For example, "1" indicates "BT. 709-5 Transfer Function (SDR)", "14" indicates "10 bit BT. 2020 Transfer Function (SDR)", and "16" indicates "SMPTE 2084 Transfer Function (HDR 1)". And “25” indicates “HDR (HDR2)”. Although “HDR (HDR2)” indicates the HDR light-to-light conversion characteristics, it is considered not to be a PQ curve but to have characteristics partially compatible with or close to conventional gamma characteristics and luminance / transmission characteristics. It is a thing.

  An 8-bit field of "color_space" indicates a color space. For example, "1" indicates "BT. 709-5", "9" indicates "BT. 2020", and "10" indicates "SMPTE 428 or XYZ".

  The 8-bit field "referencelevel" indicates a reference level (reference level). In this case, as the reference level, a value in which the relative range normalized to the maximum "1" is specified by the value of 0 to 100 is described. At the receiver, this value divided by 100 is recognized as a normalized relative reference level. The 8-bit field of "content_peak_luminance" indicates the relative value (expressed in%) of the luminance corresponding to the peak value of the transmission code included in the image. This relative value is useful, for example, to control a knee curve described later.

  Also, the container encoder 106 uses the transport stream to identify the type of subtitle data possessed by the subtitle stream SS contained in the transport stream, that is, the identification information indicating whether it is SDR data or HDR data, as the timing for switching the type of subtitle data. Further, it is inserted so as to indicate the type of subtitle data after switching from a timing earlier than a predetermined amount of time. By managing the insertion of identification information in this manner, the receiving side is notified of dynamic switching of subtitle data.

  The container encoder 109 inserts, for example, an HDR subtitle subtitle descriptor (HDR_subtitle_descriptor) that is newly defined, in association with the subtitle stream SS. This descriptor is inserted under the program map table (PMT: Program Map Table), for example, when the transport stream is a transport stream of MPEG-2 TS. Also, when the transport stream is a transport stream of MMT, this descriptor is inserted under the MP table (MPT: MMT Package Table).

  FIG. 7 shows an exemplary structure (Syntax) of the HDR subtitle descriptor. The 8-bit field of “descriptor_tag” indicates the type of descriptor, and in this case, indicates that it is an HDR subtitle descriptor. The 8-bit field of “descriptor_length” indicates the length (size) of the descriptor, and indicates the number of subsequent bytes as the length of the descriptor.

  The 1-bit flag information of “HDR_SDR_flag” indicates whether the target stream is an HDR stream or an SDR stream. "1" indicates that this is an HDR stream, and "0" indicates that this is an SDR stream. The 1-bit flag information of “subtitle_characteristics_info_flag” indicates whether or not there is characteristic information. "1" indicates that there is characteristic information, and "0" indicates that there is no characteristic information. When “subtitle_characteristics_info_flag” is “1”, 8-bit fields “transferfunction”, “color_space” and “referencelevel” are present.

  The 8-bit field of "transferfunction" indicates an electro-optical conversion characteristic (EOTF characteristic). That is, this field shows an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data. For example, "1" indicates "BT. 709-5 Transfer Function (SDR)", "14" indicates "10 bit BT. 2020 Transfer Function (SDR)", and "16" indicates "SMPTE 2084 Transfer Function (HDR 1)". And “25” indicates “HDR (HDR2)”. Although “HDR (HDR2)” indicates the HDR light-to-light conversion characteristics, it is considered not to be a PQ curve but to have characteristics partially compatible with or close to conventional gamma characteristics and luminance / transmission characteristics. It is a thing.

  An 8-bit field of "color_space" indicates a color space. For example, "1" indicates "BT. 709-5", "9" indicates "BT. 2020", and "10" indicates "SMPTE 428 or XYZ". The 8-bit field "referencelevel" indicates a reference level (reference level). In this case, as the reference level, a value in which the relative range normalized to the maximum "1" is specified by the value of 0 to 100 is described. At the receiver, this value divided by 100 is recognized as a normalized relative reference level.

  FIG. 8 shows an example of the structure of a transport stream of MPEG-2 TS. In this structural example, there are a PES packet "Video PES" of the video stream VS identified by PID1, a PES packet "Subtitle PES" of the subtitle stream SS identified by PID 2, and the data is transmitted by the carousel method. There is a data service stream DS. Although the subtitle stream SS may be transmitted by the carousel system as well as the data service, as described above, as with the data service, the contents of the subtitle stream SS are not changed thereby.

  Also, the transport stream TS includes a program map table (PMT: Program Map Table) as PSI (Program Specific Information). PSI is information that describes to which program each elementary stream included in the transport stream belongs. In PMT, there is a program loop (Program loop) that describes information related to the entire program.

  In PMT, there is an elementary stream loop having information related to each elementary stream. In this structural example, there are a video elementary stream loop (Video ES loop) corresponding to the video stream VS, and a subtitle / elementary stream loop (Subtitle ES loop) corresponding to the subtitle stream SS.

  In the video elementary stream loop, information such as stream type and PID (packet identifier) is arranged corresponding to the video stream VS, and a descriptor describing the information related to the video stream VS is also arranged. Ru. The HDR video descriptor (see FIG. 5) described above is arranged as one of the descriptors. A structure in which the HDR video descriptor is arranged under an event information table (EIT) as shown by a broken line is also conceivable.

  Further, in the subtitle, elementary stream and loop, information such as stream type and PID (packet identifier) is arranged corresponding to the subtitle stream SS, and a descriptor that describes the information related to the video stream VS is also included. Be placed. The HDR subtitle descriptor (see FIG. 7) described above is arranged as one of the descriptors.

  FIG. 9 shows an example of the structure of the MMT transport stream. In the MMT transport stream, when the packet type is “MPU”, the MPU packet “MPU video” of the video stream VS identified by ID 1 and the MPU packet “MPU subtitle” of the subtitle stream SS identified by ID 2 Is placed. Also, if the packet type is “non-timed packet”, the data service stream DS is arranged in the transport stream of this MMT.

  Also, if the packet type is “message”, various message packets are arranged in the transport stream of MMT. One of the message packets is a PA (Packet Access) message packet. The PA message packet contains a table such as MPT.

  In the MPT, information such as asset type (Asset_type) and packet ID (Packet_id) is placed corresponding to the video stream VS as an asset, and a descriptor describing information related to the video stream VS is also placed Ru. The HDR video descriptor (see FIG. 5) described above is arranged as one of the descriptors. A structure in which the HDR video descriptor is arranged under an event information table (EIT) as shown by a broken line is also conceivable.

  Also, in the MPT, information such as asset type (Asset_type), packet ID (Packet_id), etc. is placed corresponding to the subtitle stream SS as an asset, and a descriptor that describes information related to the subtitle stream SS is also Be placed. The HDR subtitle descriptor (see FIG. 7) described above is arranged as one of the descriptors.

  The operation of the service transmission system 100 shown in FIG. 2 will be briefly described. Transmission video data is input to the video encode 102, and dynamic range information and color gamut information of the transmission video data are input. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data.

  The transmission video data thus input is obtained by switching between a plurality of types of transmission video data. For a plurality of types of transmission video data, for example, a normal dynamic range transmission video data obtained by applying a normal dynamic range photoelectric conversion to a normal dynamic range video data and a high dynamic range photoelectric conversion to high dynamic range video data And includes transmission video data of high dynamic range obtained by applying.

  The video encoder 102 applies coding such as MPEG4-AVC or HEVC to the transmission video data to obtain coded video data, and a video stream VS as a component stream including the coded video data. Is generated. The video stream VS includes transmission video data as component data.

  In addition, when the video stream VS is thus generated, the video encoder 102 inserts dynamic range information and color gamut information into the video stream VS. In this case, the information (transfer function) indicating the electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic possessed by the transmission video data in the area of video usability information (VUI) of the SPS NAL unit of the access unit (AU), the color of the transmission video data Meta information such as area information and information indicating a reference level is inserted. Also, in this case, the “SEIs” portion of the access unit (AU) has meta information such as information (transfer function) indicating the electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic possessed by the transmission video data and information at the reference level. The SEI message (SEI message) is inserted.

  Also, while the image data is input to the still image encoder 104, dynamic range information and color gamut information of the image data are input. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data.

  The still picture encoder 104 performs, for example, JPEG coding on the image data to obtain coded video data. At this time, dynamic range information and color gamut information are inserted into the encoded data. In this case, for information (transfer function) indicating the electro-optical conversion characteristic, for example, the value (Value) of the gamma tag (Gamma tag) defined in the Exif (Exchangeable image file format) standard defined in the JPEG standard It is inserted using. In addition, color gamut information is inserted using, for example, the value (Value) of a color space tag (ColorSpace tag) defined by the Exif standard defined by the JPEG standard.

  Further, the graphics data is input to the data service encoder 103, and the dynamic range information and the color gamut information of the graphics data are also input. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data. Further, the encoded data obtained by the still picture encoder 104 is input to the data service encoder 103.

  The data service encoder 103 performs encoding processing on graphics data and further encoded data input from the still picture encoder 104 to generate a data service stream DS as a component stream. The data service stream DS includes image data and graphics data as component data.

  Also, when the data service stream DS is generated as described above, the data service encoder 103 inserts dynamic range information and color gamut information into the data service stream DS. In this case, the information (transfer function) indicating the electro-optical conversion characteristic is inserted, for example, by extending and defining the dynamic range information “D_range”. Also, color gamut information is inserted, for example, using the item “gfx.color_management.mode”.

  Also, subtitle data is input to the subtitle encoder 105, and dynamic range information and color gamut information of the subtitle data are input. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data.

  The subtitle encoder 105 performs encoding processing on subtitle data to generate a subtitle stream SS as a component stream. The subtitle stream SS includes subtitle data (subtitle text information such as TTML, or subtitle bitmap data) as component data.

  Also, when the subtitle stream SS is thus generated, the subtitle encoder 105 inserts dynamic range information and color gamut information into the subtitle stream SS.

  Here, when the subtitle stream SS includes TTML as subtitle text information, for example, color gamut identification information and dynamic concerning subtitle data using elements of metadata (metadata) present in the header of the TTML structure Range information is inserted. Also, when the subtitle stream SS includes subtitle bitmap data, for example, a segment including color gamut identification information and dynamic range information related to subtitle data is inserted into the subtitle stream SS.

  The video stream VS generated by the video encoder 102, the data service stream DS generated by the data service encoder 103, and the subtitle stream SS generated by the subtitle encoder 105 are supplied to the container encoder 106. The container encoder 106 generates a transport stream (a transport stream of MPEG-2 TS or MMT) including each stream.

  Also, when the transport stream is generated in the container encoder 102 in this way, identification information indicating the type of transmission video data possessed by the video stream VS contained in the transport stream is the timing at which the video stream VS is switched. Further, it is inserted so as to indicate the type of transmission video data after switching from a timing earlier by a predetermined amount of time or more. Specifically, an HDR video descriptor (see FIG. 5) is inserted corresponding to the video stream VS. Also, in the container encoder 102, an HDR subtitle descriptor (see FIG. 7) is further inserted into this transport stream in correspondence to the subtitle stream SS.

  The transport stream generated by the container encoder 106 is supplied to the transmitting unit 107. The transport stream is transmitted by the transmitter 107 to the service receiver 200 in a broadcast wave or net packet.

"Example of service receiver configuration"
FIG. 10 shows a configuration example of the service receiver 200. The service receiver 200 includes a control unit 201, a receiving unit 202, a container decoder 203, a video decoder 204, a data service decoder 205, a still image decoder 206, a subtitle decoder 207, an OSD unit 208, and a screen. A composition processing unit 209 and a monitor 210 are included.

  The control unit 201 includes a CPU (Central Processing Unit), and controls the operation of each unit of the service receiver 200 based on a control program. The receiving unit 202 receives a transport stream (a transport stream of MPEG-2 TS or MMT) as a container transmitted from the service transmission system 100 (see FIG. 2) on broadcast waves or net packets. The container decoder 203 extracts the video stream VS, the data service stream DS and the subtitle stream SS from the transport stream.

  In addition, the container decoder 203 extracts various information inserted in the transport stream, and sends the information to the control unit 201. This information also includes the HDR video descriptor (see FIG. 5) and the HDR subtitle descriptor (see FIG. 7) in which the identification information of the transmission video data described above is described.

  The control unit 201 recognizes whether the transmission video data included in the video stream Vs is SDR transmission video data or HDR transmission video data based on the description of the HDR video descriptor. As described above, the identification information of the type of transmission video data is transport as it indicates the type of transmission video data after switching from the timing earlier than the switching timing of the type of transmission video data by a predetermined time amount or more. It is inserted in the stream.

  The control unit 201 also recognizes the type of subtitle data possessed by the subtitle stream SS, that is, whether it is SDR data or HDR data, based on the description of the HDR / subtitle / descriptor. As described above, the identification information of the type of subtitle data is in the transport stream so as to indicate the type of transmission video data after switching from the timing earlier than the timing of switching the type of subtitle data by a predetermined time amount or more. It is inserted.

  The video decoder 204 decodes the video stream VS extracted by the container decoder 203 to obtain transmission video data and also obtain dynamic range information and color gamut information of the transmission video data. Here, the dynamic range information is information (transfer function) indicating an electro-optical conversion characteristic corresponding to the photoelectric conversion characteristic of the transmission video data.

  The data service decoder 205 decodes the data service stream DS extracted by the container decoder 203 to obtain graphics data (bit map data), and dynamic range information and color gamut information of the graphics data. And further obtain encoded data relating to the image data. The still image decoder 206 decodes the encoded data obtained by the data service decoder 205 to obtain image data, and obtains dynamic range information and color gamut information of the image data.

  The subtitle decoder 207 subjects the subtitle stream SS extracted by the container decoder 203 to decoding processing to obtain subtitle data (bit map data) and also acquires dynamic range information and color gamut information of the subtitle data. The OSD unit 208 outputs graphics data (bit map data) for OSD (On-screen display), and outputs dynamic range information and color gamut information of the graphics data.

  The screen synthesis processing unit 209 can transmit video data obtained by the video decoder 204, graphics data obtained by the data service decoder 205, image data obtained by the still image decoder 206, and subtitle data obtained by the subtitle decoder 207. The CPU 210 combines the graphics data obtained by the OSD unit 208 to generate display image data corresponding to the display performance of the monitor 210. The monitor 210 has display performance such as HDR and wide color gamut, or SDR and normal color gamut, and displays an image based on display image data.

  The screen combining processing unit 209 combines each data after performing brightness mapping processing so as to match display performance based on the dynamic range information of each data. The screen combining processing unit 209 combines each data after performing color gamut conversion processing so as to match display performance based on the color gamut information of each data.

  FIG. 11 shows an outline of the luminance mapping process when the display performance is HDR. Regarding transmission video data and image data, when dynamic range information indicates HDR, luminance mapping processing is performed so that the maximum value of the data bit expression range corresponds to the maximum brightness level, and dynamic range information indicates SDR. The luminance mapping process is performed so that the maximum value of the data bit expression range corresponds to the brightness reference level.

  In addition, with regard to graphics data and subtitle data, when dynamic range information indicates HDR, that is, when there is a glitter component, brightness mapping processing is performed so that the maximum value of the data bit expression range corresponds to the brightness maximum level. When the dynamic range information indicates SDR, that is, when there is no glitter component, brightness mapping processing is performed so that the maximum value of the data bit expression range corresponds to the brightness reference level.

  In this case, as the brightness reference level, for example, transmission video data, brightness reference level (reference level) set corresponding to image data (see FIG. 5) can be used, for example, graphics data, subtitle data It is also possible to use the brightness reference level (see FIG. 7) set corresponding to. Also, in this case, for transmission video data and image data, transmission video data and brightness reference level set corresponding to the image data are used, and for graphics data and subtitle data, graphics data, A brightness reference level (reference level) set corresponding to subtitle data can also be used. The brightness reference level may be 100 nits (100% brightness), but is not limited to the brightness. For example, the brightness reference level is preset to 200 nits (200% luminance) or 300 nits (300% luminance).

  FIG. 12 shows a configuration example of the screen combining processing unit 209 in the case where the display performance is HDR and in the wide color gamut. The screen combining processing unit 209 includes color gamut conversion units 211 a, 211 b, 211 c, and 211 d, luminance mapping units 212 a, 212 b, 212 c, and 212 d, a combining unit 213, and an HDR electro-optical conversion unit 214.

  The transmission video data supplied from the video decoder 204 is supplied to a series circuit of the color conversion unit 211a and the luminance mapping unit 212a. The color gamut converter 211a converts the color gamut of the transmission video data into a wide color gamut that matches the display performance of the display based on the color gamut information. For example, when the color gamut of transmission video data is "BT.709-5 = sRGB" and the color gamut that matches display performance is "BT.2020 = ITUR 2020", the color gamut of transmission video data is " It is converted from BT.709-5 "to" BT.2020 ". When the color gamut of the transmission video data is the same as the wide color gamut that matches the display performance, the color gamut conversion unit 212a outputs the input data as it is without substantially doing anything.

  The luminance mapping unit 212a performs luminance mapping on the transmission video data based on the dynamic range information so as to meet the display performance of the high dynamic range. As shown in FIG. 13, the luminance mapping unit 212 a is configured by a series circuit of an electro-optical conversion unit (EOTF unit) 221 and a photoelectric conversion unit (OETF unit) 222.

  The electro-optical conversion unit (EOTF unit) 221 converts the input transmission video data into linear light space characteristics from the photoelectric conversion characteristics (OETF characteristics) applied to the transmission video data. . The photoelectric conversion unit (OETF unit) 222 subjects the output data of the electro-optical conversion unit 221 to photoelectric conversion based on photoelectric conversion characteristics (OETF characteristics) opposite to the electro-optical conversion characteristics (EOTF characteristics) in the HDR electro-optical conversion unit 214 .

  Here, the case where the input transmission video data is SDR transmission video data will be described. In this case, the luminance mapping unit 212a converts the SDR transmission video data into HDR transmission video data by performing luminance mapping processing. In this case, as shown in FIG. 14A, the luminance mapping unit 212a is configured by a series circuit of the SDR electro-optical conversion unit 231 and the HDR photoelectric conversion unit 232, and the conversion is performed from the SDR bit space based on the brightness reference level. Performed to the HDR bit space.

In the SDR electro-optical conversion unit 231, electro-optical conversion is performed on the SDR transmission video data by the SDR electro-optical conversion characteristic indicated by an arrow a in FIG. In this case, the luminance level 0 to 100% of the input SDR transmission video data is up to 100 nits (= 100 cd / m ² ) in the linear ray space. Here, 100 nits indicates the brightness of the reference level. The brightness of the reference level is not limited to 100 nits, and may be, for example, 200 nits or 300 nits. The same applies to the other examples described below.

  Further, in the HDR photoelectric conversion unit 232, photoelectric conversion is performed by the HDR photoelectric conversion characteristic indicated by an arrow b in FIG. In this case, the output data of the SDR electro-optical conversion unit 231 is reassigned to 0 to 100 within the transmission range of 0 to N * 100. As a result, the SDR transmission video data, which was originally expressed as being full of the coding bit width, is aggregated within a partial range of the transmission range after being reassigned as the HDR transmission video data.

  Next, the input transmission video data is HDR transmission video data, and the photoelectric conversion characteristic (OETF characteristic) of this HDR transmission video data does not match the inverse characteristic of the electro-optical conversion characteristic (EOTF characteristic) in the HDR electro-optical conversion unit 214 The case will be described. When the photoelectric conversion characteristic of the HDR transmission video data matches the inverse characteristic of the electro-optical conversion characteristic of the HDR electro-optical conversion unit 214, the luminance mapping unit 212a performs the input data as it is without doing anything substantially. Output.

  In this case, the luminance mapping unit 212a converts the HDR1 transmission video data into the HDR2 transmission video data by being subjected to the luminance mapping processing. In this case, as shown in FIG. 15A, the luminance mapping unit 212a is configured by a series circuit of the HDR1 electro-optical conversion unit 241 and the HDR2 photoelectric conversion unit 242.

  The HDR1 electro-optical conversion unit 241 performs electro-optical conversion based on the HDR1 electro-optical conversion characteristic indicated by an arrow a in FIG. 15B on the HDR1 transmission video data. In this case, the luminance levels 0 to N * 100% of the input HDR1 transmission video data correspond to maximum N * 100 nits (= K1) in the linear ray space.

  Then, in this case, when N * 100% of HDR1 is larger than M * 100% of HDR2 as shown in the figure, the HDR1 electro-optical conversion unit 241 further performs 100 to N * on the signal of the electro-optical conversion input. The luminance level of 100% is converted to a luminance level of 100 to M * 100% by a knee curve (indicated by an arrow b in FIG. 15B). In FIG. 15B, “K1” indicates a luminance value [nits] corresponding to N * 100%, and “K2” indicates a luminance value [nits] corresponding to M * 100%. Although not shown, when N * 100% of HDR1 is equal to or less than M * 100% of HDR2, such luminance conversion is not performed.

  Further, in the HDR photoelectric conversion unit 242, photoelectric conversion is performed by the HDR2 photoelectric conversion characteristic indicated by an arrow c in FIG. In this case, the output data of the HDR transform unit 241 is reallocated to the entire transmission range of 0 to M * 100.

  Referring back to FIG. 12, the image data supplied from the still image decoder 206 is supplied to the series circuit of the color conversion unit 211b and the luminance mapping unit 212b. The color gamut conversion unit 211 b converts the color gamut of the image data into a wide color gamut that matches the display performance based on the color gamut information. The luminance mapping unit 212 b performs luminance mapping on the image data so as to match the display performance of the high dynamic range based on the dynamic range information. The details of the color converter 211 b and the luminance mapping unit 212 b are the same as those of the color converter 211 a and the luminance mapping unit 212 a corresponding to the above-described transmission video data, and thus the description thereof is omitted.

  Also, subtitle data supplied from the subtitle encoder 207 is supplied to the series circuit of the color conversion unit 211c and the luminance mapping unit 212c. The color gamut conversion unit 211 c converts the color gamut of the subtitle data into a wide color gamut that matches the display performance based on the color gamut information. The luminance mapping unit 212c performs luminance mapping on the subtitle data based on the dynamic range information so as to match the display performance of the high dynamic range. The details of the color conversion unit 211c and the luminance mapping unit 212c are the same as those of the color conversion unit 211a and the luminance mapping unit 212a corresponding to the above-described transmission video data, and thus will not be described.

  Also, graphics data supplied from the data service decoder 205 or the OSD unit 208 is supplied to a series circuit of the color conversion unit 211 d and the luminance mapping unit 212 d. The color gamut conversion unit 211 d converts the color gamut of the graphics data into a wide color gamut that matches the display performance based on the color gamut information. The luminance mapping unit 212 d performs luminance mapping on the graphics data to match the display performance of the high dynamic range based on the dynamic range information. The details of the color converter 211 d and the luminance mapping unit 212 d are the same as those of the color converter 211 a and the luminance mapping unit 212 a corresponding to the above-described transmission video data, and thus the description thereof is omitted.

  The transmission video data, the image data, the subtitle data and the graphic data subjected to the process of the gamut conversion and the luminance mapping are supplied to the synthesizing unit 213. Although the detailed description is omitted, the synthesizing unit 213 synthesizes each data based on the screen configuration information. The output data of the combining unit 213 is supplied to the HDR photoelectric conversion unit 214. The HDR photoelectric conversion unit 214 performs electro-optical conversion based on the HDR electro-optical conversion characteristic on the output data of the synthesis unit 213 to obtain display image data corresponding to the display performance of the HDR and the wide color gamut.

  In the above, the example has been described in which the monitor 210 has the HDR and wide color gamut display performance, and the screen combining processing unit 209 obtains display image data corresponding to the HDR and wide color gamut display performance. When the monitor 210 has the display performance of the normal color gamut such as SDR and sRGB, the screen synthesis processing unit 209 is configured to obtain display image data corresponding to the display performance of the SDR and the normal color gamut.

  In this case, in the screen synthesis processing unit 209 shown in FIG. 12, each color gamut conversion unit converts the color gamut of each data into a normal color gamut that matches the display performance based on the color gamut information. Further, in the screen synthesis processing unit 209 shown in FIG. 12, in each luminance mapping unit, luminance mapping is performed on each data so as to match the display performance of the normal dynamic range based on the dynamic range information. In the screen synthesis processing unit 209 illustrated in FIG. 12, the HDR electro-optical conversion unit 214 is an SDR electro-optical conversion unit.

  Here, a case where input transmission video data is HDR transmission video data will be described. In this case, the luminance mapping unit converts the HDR transmission video data into SDR transmission video data by performing luminance mapping processing. In this case, as shown in FIG. 16A, the luminance mapping unit is configured by a series circuit of the HDR electro-optical conversion unit 251 and the SDR photoelectric conversion unit 252.

The HDR electro-optical conversion unit 251 subjects the HDR transmission video data to electro-optical conversion based on the HDR electro-optical conversion characteristic indicated by the arrow a in FIG. In this case, the luminance levels 0 to N * 100% of the input HDR transmission video data become maximum N * 100 nits (= 100 cd / m ² ) in the linear ray space.

  Then, in this case, the HDR electro-optical conversion unit 251 further generates a knee curve (see FIG. 6) for the luminance conversion level lower than 100% to the luminance level of N * 100% with respect to the signal of the electro-optical conversion input. The luminance level is converted to a luminance level equal to or less than the 100% transmission range of the SDR OETF by the arrow 16 b).

  Further, in the SDR photoelectric conversion unit 252, photoelectric conversion is performed by the SDR photoelectric conversion characteristic indicated by the arrow c in FIG. In this case, the output data of the HDR transform unit 251 is reassigned to the entire transmission range of 0 to 100.

  The operation of the service receiver 200 shown in FIG. 10 will be briefly described. The reception unit 202 receives a transport stream (a transport stream of MPEG-2 TS or MMT) transmitted from the service transmission system 100 on broadcast waves or net packets. This transport stream is supplied to the container decoder 203. The container decoder 203 extracts the video stream VS, the data service stream DS and the subtitle stream SS from the transport stream.

  The container decoder 203 extracts various information inserted in the transport stream as a container, and sends the information to the control unit 201. This information also includes the HDR video descriptor (see FIG. 5) and the HDR subtitle descriptor (see FIG. 7) described above.

  The control unit 201 recognizes, based on the description of the HDR video descriptor, whether the transmission video data included in the video stream Vs is SDR transmission video data or HDR transmission video data. Further, the control unit 201 recognizes the type of subtitle data possessed by the subtitle stream SS, that is, whether it is SDR data or HDR data, based on the description of the HDR / subtitle / descriptor.

  The video stream VS extracted by the container decoder 203 is supplied to the video decoder 204. The video decoder 204 decodes the video stream VS to obtain transmission video data, and also to obtain dynamic range information and color gamut information of the transmission video data.

  Also, the data service stream DS extracted by the container decoder 203 is supplied to the data service decoder 205. The data service decoder 205 decodes the data service stream DS to obtain graphics data (bit map data), and obtains dynamic range information and color gamut information of the graphics data, and further, an image. Encoded data relating to the data is obtained.

  The encoded data relating to the image data obtained by the data service decoder 205 is supplied to the still image decoder 206. The still image decoder 206 decodes the encoded data to obtain image data, and also obtains dynamic range information and color gamut information of the image data.

  Also, the subtitle stream SS extracted by the container decoder 203 is supplied to the subtitle decoder 207. The subtitle decoder 207 performs a decoding process on the subtitle stream SS to obtain subtitle data (bit map data) and to obtain dynamic range information and color gamut information of the subtitle data.

  Transmission video data obtained by the video decoder 204, graphics data obtained by the data service decoder 205, image data obtained by the still picture decoder 206, subtitle data obtained by the subtitle decoder 207, and obtained by the OSD unit 208 The graphics data is supplied to the screen synthesis processing unit 209 together with the respective dynamic range information and color gamut information.

  The screen combining processing unit 209 combines each data to generate display image data corresponding to the display performance of the monitor 210. In this case, each data is subjected to color gamut conversion processing to match display performance based on the color gamut information of each data, and further, brightness to match display performance based on each data dynamic range information. It is synthesized after the mapping process is performed. The display image data generated by the screen synthesis processing unit 209 is supplied to the monitor 210, and an image by the display image data is displayed on the monitor 210.

  As described above, in the transmission / reception system 10 shown in FIG. 1, the service transmission system 100 transmits component data (transmission video) to each component stream (video stream VS, data service stream DS, subtitle stream SS). Insert dynamic range information of data, image data, graphics data, subtitle data). Therefore, on the receiving side, it is possible to obtain output data by combining each component data after performing luminance mapping processing to match display performance based on the respective dynamic range information.

  In this case, since the characteristics of electro-optical conversion to be applied to the output data can be fixed (see the HDR electro-optical conversion unit 214 in FIG. 12), it is possible to prevent the occurrence of distortion due to switching of the electro-optical conversion characteristics. For example, when graphics are displayed together with an image by video data, even if the image by video data is switched from SDR to HDR or from HDR to SDR, there is no change in color or brightness in graphics display. Further, in this case, since the luminance mapping process is performed on each component data so as to match the display performance, it is possible to always display the display by each component data in an appropriate luminance state.

  For example, FIGS. 17 (a) and 17 (b) show an example of graphic display by so-called "d button" operation existing as one of the broadcast services. A moving image by transmission video data is displayed in a small window at the upper right, and a still image by image data is displayed at the lower left.

  FIG. 17A shows an example of switching the characteristics of electro-optical conversion to be applied to transmission video data depending on whether the transmission video data is SDR transmission video data or HDR transmission video data. In this case, the color and the luminance of the graphic display are influenced at the time of switching between the SDR image display and the HDR image display.

  FIG. 17B shows the case where the characteristic of electro-optical conversion to be applied to transmission video data is fixed regardless of whether the transmission video data is SDR transmission video data or HDR transmission video data as in the present technology. It is an example. In this case, the color and the luminance of the graphics display are not affected when switching between the SDR image display and the HDR image display.

  Further, in the transmission / reception system 10 shown in FIG. 1, the service transmission system 100 inserts color gamut information of component data of each component stream into each component stream. Therefore, it is possible to obtain output data by combining each component data after performing color gamut conversion to suit display performance based on the respective color gamut information on the receiving side, and the display by each component data is always appropriate It is possible to display in various color states.

<2. Modified example>
Although the transmission / reception system 10 including the service transmission system 100 and the service receiver 200 is described in the above embodiment, the configuration of the transmission / reception system to which the present technology can be applied is not limited to this. . For example, the service receiver 200 may be configured of, for example, a set top box (STB) and a monitor connected by a digital interface such as a high-definition multimedia interface (HDMI). "HDMI" is a registered trademark.

  Further, in the above-described embodiment, an example has been shown in which the container is a transport stream of MPEG-2 TS (MPEG-2 Transport Stream) or MMT (MPEG Media Transport). However, the container to which the present technology can be applied is not limited to this, and may be a container of another format such as MP4.

Furthermore, the present technology can also be configured as follows.
(1) A predetermined format including a predetermined number of second component streams having other component data, together with a first component stream having transmission video data obtained by switching transmission video data of a plurality of types as component data A transmitter for transmitting a container,
A transmitter comprising: an information insertion unit for inserting dynamic range information of component data of each component stream into each of the component streams.
(2) The information insertion unit
The transmitting device according to (1), further inserting color gamut information of component data of each component stream into each of the component streams.
(3) Transmission after switching in the layer of the container, identification information indicating the type of transmission video data possessed by the first component stream included in the container, from timing earlier than the switching timing by a predetermined time amount or more The transmission device according to (1) or (2), further including an information insertion unit that inserts data so as to indicate a type of video data.
(4) The transmission device according to any one of (1) to (3), wherein the predetermined number of second component streams include a data broadcast stream and / or a subtitle stream.
(5) The transmitter transmits a predetermined number of second component streams having other component data together with the first component stream having component video data obtained by switching transmission video data of a plurality of types. Sending the container in a predetermined format including:
A transmission method comprising: an information inserting step of inserting dynamic range information of component data of each component stream into each of the component streams.
(6) A predetermined format including a predetermined number of second component streams having other component data, together with a first component stream having transmission video data obtained by switching plural types of transmission video data as component data It has a receiver that receives containers,
Dynamic range information of the component data of each component stream is inserted in each of the above component streams,
The system further comprises a processing unit that decodes each of the component streams to obtain a plurality of component data and combines the obtained plurality of component data to obtain output data.
The above processing unit
A receiver according to the present invention, wherein the above component data are subjected to luminance mapping processing so as to match display performance based on respective dynamic range information, and then combined to obtain the above output data.
(7) The color gamut information of the component data of each component stream is further inserted into each of the above component streams,
The above processing unit
The receiving apparatus according to (6), wherein the component data is subjected to color gamut conversion processing so as to match display performance based on respective color gamut information, and then combined to obtain the output data.
(8) A predetermined number of second component streams having other component data together with the first component stream having transmission video data obtained by switching the plurality of types of transmission video data as component data by the reception unit Receiving a container of a predetermined format including:
Dynamic range information of the component data of each component stream is inserted in each of the above component streams,
The method further includes a processing step of decoding each of the component streams to obtain a plurality of component data, and combining the obtained plurality of component data to obtain output data.
In the above processing step,
A receiving method for obtaining the above output data by combining each component data described above with luminance mapping processing so as to match display performance based on respective dynamic range information.

  The main feature of this technology is that by inserting the dynamic range information of component data possessed by each component stream into each component stream and transmitting it, it becomes possible to fix the characteristics of electro-optical conversion on the receiving side, and the electro-optical conversion characteristics It is possible to prevent the occurrence of distortion due to switching (see FIG. 2).

10: Transmission / reception system 100: Service transmission system 101: Control unit 102: Video encoder 103: Data service encoder 104: Still image encoder 105: Subtitle encoder 106: Container Encoder 107 ... Transmission unit 200 ... Service receiver 201 ... Control unit 202 ... Reception unit 203 ... Container decoder 204 ... Video decoder 205 ... Data service decoder 206 ... Stationary Image decoder 207: Subtitle decoder 208: OSD unit 209: Screen combination processing unit 210: Monitor 211a, 211b, 211c, 211d: Color gamut conversion unit 212a, 212b, 212c, 212d,. · Luminance mapping unit 213 ... combining unit 214 ··· HDR light-to-light converter 221 ··· light-to-light converter (EOTF unit)
222: Photoelectric conversion unit (OETF unit)
231 ... SDR light-to-light conversion unit 232 ... HDR photoelectric conversion unit 241 ... HDR1 light-to-light conversion unit 242 ... HDR2 photoelectric conversion unit 251 ... HDR electric-to-light conversion unit 252 ... SDR photoelectric conversion unit

Claims (8)

A container of a predetermined format including a predetermined number of second component streams having other component data is transmitted together with the first component stream having transmission video data obtained by switching plural types of transmission video data as component data The transmitter to
A transmitter comprising: an information insertion unit for inserting dynamic range information of component data of each component stream into each of the component streams. The information insertion unit
The transmission apparatus according to claim 1, further comprising: color gamut information of component data of each component stream, inserted into each of the component streams. In the layer of the container, identification information indicating the type of transmission video data of the first component stream included in the container is transmitted video data after switching from a timing earlier by a predetermined time than the switching timing. The transmission device according to claim 1, further comprising an information insertion unit that inserts information so as to indicate a type. The transmission apparatus according to claim 1, wherein the predetermined number of second component streams include a data broadcast stream and / or a subtitle stream. A predetermined format including a predetermined number of second component streams having other component data together with a first component stream having transmission video data obtained by switching a plurality of types of transmission video data as component data by the transmission unit A sending step of sending a container of
A transmission method comprising: an information inserting step of inserting dynamic range information of component data of each component stream into each of the component streams. Receiving a container of a predetermined format including a predetermined number of second component streams having other component data, together with a first component stream having transmission video data obtained by switching between plural types of transmission video data as component data Equipped with a receiver to
Dynamic range information of the component data of each component stream is inserted in each of the above component streams,
The system further comprises a processing unit that decodes each of the component streams to obtain a plurality of component data and combines the obtained plurality of component data to obtain output data.
The above processing unit
A receiver according to the present invention, wherein the above component data are subjected to luminance mapping processing so as to match display performance based on respective dynamic range information, and then combined to obtain the above output data. The color gamut information of the component data of each component stream is further inserted into each of the above component streams,
The above processing unit
The receiver according to claim 6, wherein each of the component data is subjected to color gamut conversion processing so as to match display performance based on each color gamut information and then combined to obtain the output data. A predetermined format including a predetermined number of second component streams having other component data together with a first component stream having transmission video data obtained by switching a plurality of types of transmission video data as component data by the receiving unit Receiving a container of
Dynamic range information of the component data of each component stream is inserted in each of the above component streams,
The method further includes a processing step of decoding each of the component streams to obtain a plurality of component data, and combining the obtained plurality of component data to obtain output data.
In the above processing step,
A receiving method for obtaining the above output data by combining each component data described above with luminance mapping processing so as to match display performance based on respective dynamic range information.

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