JP2021164090A - Video processing apparatus, television receiver, and program - Google Patents

Abstract

To suppress a program from being displayed darkly.SOLUTION: A video processing apparatus includes a brightness information acquisition unit for acquiring the brightness information of the video of the program in the television broadcast received by a receiving unit, a determination unit for determining the video system of the program on the basis of the brightness information, and a correction unit for performing a gain correction process to increase the brightness level when the program is displayed on a display unit. The video system includes a second video system in which the resolution is a first resolution, and a second video system in which a pre-conversion video having a second resolution lower than the first resolution is enlarged and converted in the resolution and dynamic range. The correction unit executes the gain correction process when the determination unit determines that the program is created in the second video system.SELECTED DRAWING: Figure 1

Description

The present invention relates to a video processing device, a television receiver, and a program.

In order to specify standard operation guidelines when handling HDR (High Dynamic Range) video in studio program production and program transmission at broadcasting stations, "ARIB TR-B43: Operation of program production using high dynamic range video" "Guidelines" (Non-Patent Document 1) have been formulated. The ARIB TR-B43 stipulates that when mapping an SDR (Standard Dynamic Range) signal to an HLG (Hybrid Log-Gamma) signal, 100% SDR signal is assigned to a 75% HLG signal level (ARIB). TR-B43 See Chapter 2.3, “Reference Levels in Mapping SDR Signals to HLG Signals”).

"Operational Guidelines for Program Production Using High Dynamic Range Video", Association of Radio Industries and Businesses, ARIB TR-B43 1.2 Edition, revised on July 30, 2019

The brightness level of 75% of the HDR video converted from the SDR video based on the provisions described in Non-Patent Document 1 is assigned to the brightness level of 100% of the SDR video before conversion. Therefore, when displaying the converted HDR video, it may be displayed darker than the SDR video before conversion. For example, when the converted HDR image is displayed on a display device that displays 100% brightness level of each of the SDR image and the HDR image with the same brightness, the image is displayed as compared with the case where the SDR image before the change is displayed. It may be displayed dark.

In view of the above-mentioned problems, a main object of the present disclosure is to prevent the program from being displayed darkly.

The video processing device according to one aspect of the present disclosure determines the brightness information acquisition unit that acquires the brightness information of the video of the program in the television broadcast received by the reception unit and the video method of the program based on the brightness information. It includes a determination unit and a correction unit that performs a gain correction process for increasing the brightness level when the program is displayed on the display unit. The video system includes a first video system having a first resolution and a second video system in which a pre-conversion video having a second resolution lower than the first resolution is expanded and converted in resolution and dynamic range. When the determination unit determines that the program is the second video system, the correction unit executes the gain correction process.

The television receiver according to one aspect of the present disclosure includes the video processing device, the receiving unit, and the display unit.

The program according to one aspect of the present disclosure causes a computer system to execute a luminance information acquisition process, a determination process, and a gain correction process. In the luminance information acquisition process, the luminance information of the video of the program in the television broadcast received by the receiving unit is acquired, and in the determination process, the luminance information of the program is determined based on the luminance information, and the gain correction process is performed. Then, the brightness level when the program is displayed on the display unit is increased. The video system includes a first video system having a first resolution and a second video system in which a pre-conversion video having a second resolution lower than the first resolution is expanded and converted in resolution and dynamic range. The gain correction process is executed when the determination process determines that the program is the second video system.

It is a block diagram of the television receiver including the image processing apparatus which concerns on 1st Embodiment. This is an example of a video. This is an example of a histogram of the brightness of an image in which the image system is a pure 4K system. This is an example of a histogram of the brightness of an image in which the image system is the conversion HLG method. It is an operation flowchart of the image processing apparatus and the television receiver which concerns on 1st Embodiment. It is an operation flowchart of the image processing apparatus and the television receiver which concerns on 2nd Embodiment. It is an operation flowchart of the image processing apparatus and the television receiver which concerns on 3rd Embodiment.

The embodiments described below are merely examples of the present disclosure, and the present disclosure is not limited to the embodiments. Even if it is not the embodiment, various changes can be made according to the design and the like as long as it does not deviate from the technical idea of the present disclosure.

(First Embodiment)
Hereinafter, the video processing device 1, the television receiver 10, and the program according to the present embodiment will be described with reference to FIG.

FIG. 1 is a block diagram of a television receiver including a video processing device according to the first embodiment.

The television receiver 10 of the present embodiment is configured to display a received television broadcast program. The television receiver 10 includes a video processing device 1, a receiving unit 2, a display unit 3, and a speaker 4.

The display unit 3 is, for example, a liquid crystal display. The display unit 3 displays the video of the program based on the video control signal output from the video processing device 1.

The speaker 4 outputs the sound of the program based on the sound control signal output from the video processing device 1.

The receiving unit 2 is configured to receive a television broadcast program distributed by a broadcasting company. The receiving unit 2 includes a tuner 21. The tuner 21 receives the television broadcast wirelessly or by wire. When wireless is used for receiving television broadcasting, a wireless antenna is connected to the antenna input terminal of the tuner 21 via, for example, an antenna cable. When wired communication is used for receiving television broadcasting, a terminal device for wired communication (for example, optical communication using an optical fiber) is connected to the antenna input terminal of the tuner 21 via, for example, an antenna cable.

Television broadcasting includes terrestrial broadcasting (terrestrial digital television broadcasting) and satellite broadcasting. Satellite broadcasting includes BS (Broadcasting Satellites) broadcasting, CS (Communication Satellites) broadcasting, new 4K8K satellite broadcasting, and the like. The tuner 21 may support only one of terrestrial broadcasting and satellite broadcasting. Further, the tuner 21 may support only one of the BS / CS broadcasting and the 4K8K satellite broadcasting among the satellite broadcasting. In the present embodiment, the tuner 21 supports the new 4K8K satellite broadcast and receives the new 4K8K satellite broadcast (television broadcast). The receiving unit 2 may include a plurality of tuners including a terrestrial digital tuner compatible with terrestrial broadcasting and a BS / CS tuner compatible with BS / CS broadcasting.

Here, for a program having a resolution of 4K (3840 x 2160, first resolution) (hereinafter, also referred to as a 4K program) delivered by the new 4K8K satellite broadcast, the video system is the pure 4K system (first video system). A program that is a conversion HLG (Hybrid Log-Gamma) system (second video system) is mixed.

An image whose image system is a pure 4K system (hereinafter, also referred to as a pure 4K image) is an image generated by using equipment such as a 4K camera, and has a resolution of 4K at the time of generation. In addition, pure 4K video includes video (also referred to as HDR pure 4K video) whose dynamic range is HDR (High Dynamic Range, first range) of the HLG system, and SDR (Standard Dynamic Range,) whose dynamic range is narrower than HDR. The image (also referred to as SDR pure 4K image) which is the second range) is mixed.

On the other hand, the video whose video format is the conversion HLG method (hereinafter, also referred to as the converted HLG video) is a dynamic 2K video (pre-conversion video) whose resolution is lower than 4K (1920 × 1080, second resolution). This is an image in which the range and resolution are enlarged and converted (up-converted). The 2K video has a resolution of 2K and a dynamic range of SDR, whereas the converted HLG video has a resolution of 4K and a dynamic range of HDR of the HLG system.

In "ARIB TR-B43 (1.2 version): Operation guideline for program production using high dynamic range video", "When mapping SDR signal to HLG signal, 100% SDR signal is 75% HLG signal level. Allocate to. " That is, the signal level of 100% of the 2K video (SDR signal) corresponds to the signal level of 75% of the HLG video (HLG signal). For example, in the 2K video, the signal level corresponding to the reference white is 100% (first level), whereas in the converted HLG video, the signal level corresponding to the reference white is 75% (first level) lower than 100%. 2 levels). The reference white is a signal level when an image is taken on a uniformly diffuse reflection surface having a brightness rate of 100% illuminated under predetermined operating conditions. Further, "% HLG" is a percentage notation of the video signal level normalized to [0: 1] by the optical electro transfer function (OETF) of the HLG system.

A plurality of frequency bands (channels) are assigned to television broadcasting. Each of the plurality of broadcasters distributes the program using the channel assigned to them. That is, the television broadcast includes a plurality of programs. The tuner 21 performs signal processing (for example, signal extraction, signal amplification, decoding, etc.) on a television broadcast based on any one of a plurality of channels selected, thereby performing signal processing (for example, signal extraction, signal amplification, decoding, etc.) on the selected channel. The data corresponding to is output to the video processing device 1.

The data output from the receiving unit 2 to the video processing device 1 includes a video signal, an audio signal, and the like of the program corresponding to the selected channel. The signal level of the video signal indicates the brightness level for each pixel, color information, and the like. The video processing device 1 causes the display unit 3 to display a program (video) based on the video signal. The detailed configuration of the video processing device 1 will be described later. In the present disclosure, the "program in the television broadcast received by the receiver 2" is a program corresponding to the channel selected to be displayed on the display unit 3 among the plurality of programs included in the television broadcast. In the following description, the "program in the television broadcast received by the receiving unit 2" may be referred to as a "display program".

In addition, program information is added to the television broadcast. The program information is, for example, SI (Service Information). The program information is information corresponding to each program in a predetermined period (for example, 8 days). The program information includes, for example, information indicating a program name (title and subtitle), broadcast date and time, program content, program attributes, and the like. The program content is, for example, a description of the program, genre information indicating the genre of the program (for example, a movie, sports, animation, news, etc.), information indicating a performer, or the like. The program attribute is, for example, information indicating the resolution, aspect ratio, frame rate, audio mode, video system, presence / absence of subtitles, etc. of the program. In addition, the program information includes business information indicating a broadcaster of the program.

The data output from the receiving unit 2 to the video processing device 1 includes the program information of the broadcasting company corresponding to the selected channel. This program information is stored in, for example, a non-volatile memory.

The video processing device 1 displays a video (program) by controlling the display unit 3 based on the data from the receiving unit 2 (tuner 21). The video processing device 1 includes a separation unit 11, a display control unit 12, an audio control unit 13, a luminance information acquisition unit 14, a program guide generation unit 15, a determination unit 16, and a correction unit 17. The video processing device 1 is composed of, for example, a microcomputer having a processor and a memory. That is, the video processing device 1 is realized by a computer system having a processor and a memory. Then, when the processor executes an appropriate program, it functions as a separation unit 11, a display control unit 12, a voice control unit 13, a luminance information acquisition unit 14, a program guide generation unit 15, a determination unit 16, and a correction unit 17. .. The program may be pre-recorded in a memory, may be recorded through a telecommunication line such as the Internet, or may be recorded and provided on a non-temporary recording medium such as a memory card. A processor in a computer system is composed of one or more electronic circuits including a semiconductor integrated circuit (IC) or a large scale integrated circuit (LSI). A plurality of electronic circuits may be integrated on one chip, or may be distributed on a plurality of chips. The plurality of chips may be integrated in one device, or may be distributed in a plurality of devices. For example, the separation unit 11, the display control unit 12, the voice control unit 13, the luminance information acquisition unit 14, the program guide generation unit 15, the determination unit 16, and the correction unit 17 may be realized by a plurality of microcomputers.

The separation unit 11 separates the video data, the audio data, and the program information from the output data of the reception unit 2. The separation unit 11 outputs video data to the display control unit 12 and the luminance information acquisition unit 14, outputs audio data to the audio control unit 13, and outputs program information to the program guide generation unit 15.

The display control unit 12 outputs the display control signal generated based on the video data to the display unit 3, so that the display unit 3 displays the video of the program. Here, the video data of the present embodiment includes luminance data (luminance value) (Y) indicating the luminance of each pixel of the video of the program and color difference data (Cb, Cr). The display control unit 12 generates a display control signal by correcting (gamma correction) the luminance data included in the video data by using a gamma curve. Specifically, when the dynamic range of the video data is the HDR of the HLG system, the display control unit 12 performs gamma correction using the HLG gamma curve. Further, when the dynamic range of the video data is SDR, the display control unit 12 performs gamma correction using the SDR gamma curve. The video data may be configured to include RGB color data, and even in this case, the luminance data can be calculated from the RGB color data.

The voice control unit 13 outputs the sound of the program from the speaker 4 by outputting the voice control signal generated based on the voice data to the speaker 4.

The luminance information acquisition unit 14 acquires the luminance information indicating the luminance value of each pixel of the video of the program from the video data from the separator 11. For example, the luminance information acquisition unit 14 acquires the luminance data (Y) indicating the luminance of each pixel of the video of the program included in the luminance information as the luminance information. Further, the luminance information acquisition unit 14 generates a luminance histogram (distribution of luminance values) from the luminance data indicating the luminance of each pixel of the image of the program included in the luminance information data of a predetermined time length, and the generated histogram is used as the luminance. It may be information. The luminance information acquisition unit 14 outputs the luminance information to the determination unit 16.

The program guide generation unit 15 generates an electronic program guide (EPG: Electronic Programming Guide) based on the program information. The program guide generation unit 15 generates an electronic program guide by arranging programs in chronological order for each channel (broadcaster). In the electronic program guide, at least the program name is described in the column (program column) corresponding to each program. The electronic program guide generated by the program guide generation unit 15 is stored in, for example, a non-volatile memory. Further, the electronic program guide is displayed on the display unit 3 and is used for searching programs being broadcast and scheduled to be broadcast. In addition, the electronic program guide includes genre information indicating the genre of each program (for example, movie, sports, animation, news, etc.).

In addition, a logo may be described in the program column according to the program attribute of the program. The program attribute includes an item (logo item) corresponding to the logo. For example, the program attribute includes an item indicating the presence or absence of subtitles as a logo item. When the program attribute includes the information "with subtitles", the program guide generation unit 15 displays the logo "character" in the program column. In addition, the program attribute includes an item indicating a video system as a logo item. When the program attribute includes the information that "the video system is pure 4K", the program guide generation unit 15 displays the logo "4K" in the program column. Further, when the program attribute includes the information "HDR pure 4K video", the program guide generation unit 15 displays the logo "HDR" in the program column. There are other logo items besides the above, such as "Bilingual broadcasting", "5.1ch surround broadcasting", "Rebroadcasting", etc., and if applicable, the corresponding logo is available. Described in the program column.

The program information is transmitted in the text data format, and the program guide generation unit 15 may display the text data in the program column. In this case, the logo may be transmitted by, for example, a ward code.

Further, in the present embodiment, the program guide generation unit 15 generates an electronic program guide based on the program information included in the television broadcast, but the present invention is not limited to this. For example, the program guide generation unit 15 may generate an electronic program guide based on the program information acquired from the server. In this case, the television receiver 10 includes a communication unit (for example, a communication interface) that can be connected to an Internet line. The server stores the program information of each broadcaster of each television broadcast. The program guide generation unit 15 acquires program information from the server via the communication unit and the Internet line, and generates an electronic program guide for each television broadcast. Further, the program guide generation unit 15 may simply output the program information acquired from the television broadcast or the server or the like to the determination unit 16.

The determination unit 16 performs a determination process of determining the video system of the program (display program) in the television broadcast received by the reception unit 2 based on the brightness information of the display program. Specifically, the determination unit 16 determines whether or not the video system of the displayed program is the conversion HLG system (second video system) based on the luminance information from the luminance information acquisition unit 14. Specifically, for example, in the brightness information, the determination unit 16 uses the conversion HLG method (second video method) as the video method of the displayed program based on whether or not the maximum value of the brightness value is equal to or less than the threshold value. Judge whether or not. For example, the determination unit 16 determines in the luminance information that the video system of the displayed program is the conversion HLG system when the maximum value of the luminance value is equal to or less than the threshold value. For example, in the luminance information, when the maximum value of the luminance value is not equal to or less than the threshold value, the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system).

Further, the determination unit 16 may determine the video system of the program (display program) in the television broadcast received by the reception unit 2 based on the genre of the display program and the brightness information of the display program. Further, the determination unit 16 may determine the video system of the program (display program) in the television broadcast received by the reception unit 2 based on the current time and the brightness information of the display program.

Here, the brightness value of the pure 4K image of the pure 4K method and the brightness value of the converted HLG image of the conversion HLG method will be described with reference to FIGS. 2 to 4.

When the video system of the displayed program is the pure 4K system, the range of the luminance value is 16 to 235. As described above, in the 2K video (pre-conversion video) which is the video before conversion of the converted HLG video, the signal level corresponding to the reference white is 100%, whereas in the converted HLG video, it corresponds to the reference white. The signal level to be used is 75%. Therefore, the range of the brightness value of the video data of the converted HLG video is in the range of 16 to 176 (≈235 * 0.75). That is, the video data of the converted HLG video does not include a region where the brightness level is greater than 75%. However, strictly speaking, the 2K video (video before conversion) contains super white whose signal level is slightly higher than the reference white, and the video data of the converted HLG video has a brightness level of 75% (brightness value is 176). May also contain large values.

For example, it is assumed that the video signal of the television broadcast received by the receiving unit 2 has a rectangular white region in the center and a black region around the white region as shown in FIG. When the image shown in FIG. 2 is an image generated by using equipment such as a 4K camera, is a pure 4K image having a resolution of 4K at the time of generation, and the image method is a pure 4K method, the brightness information. When the acquisition unit 14 generates a histogram of brightness, a histogram as shown in FIG. 3 is obtained.

FIG. 3 is an example of a histogram of the brightness of an image in which the image system is a pure 4K system. In FIG. 3, the horizontal axis represents the luminance value and the vertical axis represents the number of pixels.

The histogram of FIG. 3 shows that there are 16 pixels having a luminance value corresponding to black in FIG. 2 and 235 pixels having a luminance value corresponding to white in FIG. When the video system is a pure 4K system, the range of the brightness value is in the range of 16 to 235. Therefore, when there are pixels having a brightness value of 235 as shown in the histogram of FIG. 3, the video system is the pure 4K system. You can see that.

Further, the video shown in FIG. 2 is a 2K video having a resolution lower than 4K (1920 × 1080), and the dynamic range and resolution are enlarged and converted (up-converted), and the video system is the conversion HLG system. In some cases, when the brightness information acquisition unit 14 generates a histogram of brightness, a histogram as shown in FIG. 4 is obtained.

FIG. 4 is an example of a histogram of the brightness of an image in which the image system is the conversion HLG method. In FIG. 4, the horizontal axis represents the luminance value and the vertical axis represents the number of pixels.

The histogram of FIG. 4 shows that there are 16 pixels having a luminance value corresponding to black in FIG. 2 and 176 pixels having a luminance value corresponding to white in FIG. As described above, in the 2K video (pre-conversion video) which is the video before conversion of the converted HLG video, the signal level corresponding to the reference white is 100%, whereas in the converted HLG video, it corresponds to the reference white. The signal level to be used is 75%. Therefore, when the video system is the conversion HLG system, the range of the brightness value is in the range of 16 to 176, so that the maximum value of the brightness value is 176 and the pixel has a brightness value of 177 or more as shown in the histogram of FIG. If there is no such, it is highly likely that the video system is the conversion HLG system. Note that FIG. 4 shows a case where the super white is not included, and when the case where the super white is included is also taken into consideration, when the maximum value of the brightness value is 180 or less, the video system may be the conversion HLG method. Is considered to be high.

The explanation will be continued by returning to FIG.

The correction unit 17 executes a gain correction process for increasing the brightness level when the displayed program is displayed on the display unit 3. The gain correction process is a process for increasing the gain of the gamma curve (HLG gamma curve) used when the display control unit 12 generates a display control signal based on the video data. Here, "increasing the gain of the HLG gamma curve" means multiplying the HLG gamma curve by a coefficient (correction coefficient) of 1 or more. When the correction unit 17 executes the gain correction process, the display control unit 12 generates a display control signal using the corrected HLG gamma curve. As a result, the brightness level when the displayed program is displayed on the display unit 3 is increased as compared with the case where the gain correction process is not executed.

The correction unit 17 executes the gain correction process based on the result of the determination process of the determination unit 16. When the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, the correction unit 17 executes the gain correction process. When the determination unit 16 determines that the video system of the display program is the pure 4K system, in other words, the video system of the display program is not the conversion HLG system, the correction unit 17 does not execute the gain correction process.

As described above, in the 2K video (pre-conversion video) which is the video before conversion of the converted HLG video, the signal level corresponding to the reference white is 100%, whereas in the converted HLG video, it corresponds to the reference white. The signal level to be used is 75%. Therefore, the video data of the converted HLG video does not include a region where the brightness level is greater than 75%. Strictly speaking, the 2K video (video before conversion) contains super white whose signal level is slightly higher than the reference white, and the video data of the converted HLG video contains a value whose brightness level is greater than 75%. In some cases.

In the present embodiment, when the video system of the display program is the conversion HLG system, the display control unit 12 generates a display control signal using the corrected HLG gamma curve. That is, the display control signal may include a region where the luminance level is greater than 75%. As a result, it is possible to prevent the converted HLG video, which is a display program, from being displayed darker than the pure 4K video.

The correction coefficient used for the gain correction process is determined based on the signal level ratio between the 2K video and the converted HLG video. Specifically, the signal level corresponding to the reference white in the 2K video is 100% (first level), and the signal level corresponding to the reference white in the converted HLG video is 75% (second level). The correction coefficient is a value (= 1.25) of the ratio of the first level (100%) to the second level (75%). Therefore, while the upper limit of the brightness level of the converted HLG image is 75%, the upper limit of the brightness level of the display control signal after the gain correction processing is 100%. As a result, the upper limit of the brightness level of the converted HLG image can be made equal to the upper limit of the brightness level of the pure 4K image. In the present embodiment, the correction coefficient is 1.25, but the upper limit of the brightness level of the display control signal after the gain correction processing may be a value close to 100%, and is not limited to 1.25. For example, it may be 1.33.

Next, an operation example of the video processing device 1 and the television receiver 10 of the first embodiment will be described with reference to FIG.

FIG. 5 is an operation flowchart of the video processing device and the television receiver according to the first embodiment.

First, the receiving unit 2 receives a television broadcast (new 4K8K satellite broadcast) (S501). Then, the receiving unit 2 outputs the data corresponding to the selected channel to the video processing device 1. Here, it is assumed that the channel corresponding to the 4K program is selected.

Next, the luminance information acquisition unit 14 acquires the luminance information indicating the luminance value of each pixel of the video of the display program from the video data of the display program (S502). Specifically, for example, the luminance information acquisition unit 14 acquires the luminance data (Y) indicating the luminance of each pixel of the video of the display program included in the video data having a predetermined time length as the luminance information.

Next, the determination unit 16 performs a determination process for determining the video system of the displayed program based on the luminance information. In the present embodiment, the determination unit 16 refers to the luminance information acquired by the luminance information acquisition unit 14. Then, the determination unit 16 determines whether or not the maximum value of the luminance value is equal to or less than the threshold value in the luminance information (S503). For example, in the first embodiment, 180 is used as the threshold value. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the threshold value (see, for example, FIG. 4) (S503: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system. When it is determined that the maximum value of the luminance value is not equal to or less than the threshold value (for example, see FIG. 3) (S503: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system). Is determined.

As described above, the video data of the converted HLG video usually does not include a region where the brightness level is greater than 75%, but strictly speaking, the 2K video (video before conversion) has a signal level higher than that of the reference white. A slightly higher super white may be included, and the video data of the converted HLG video may contain a value having a brightness level greater than 75%. That is, the brightness value of the video data of the converted HLG video is usually in the range of 16 to 176, but when super white is included, the brightness value may be slightly larger than 176. Therefore, in consideration of the case where super white is included, 180 larger than 176 is used as the threshold value used for determining whether or not the video system is the pure 4K system. When super white is not taken into consideration, for example, 176 may be used as the threshold value.

When it is determined in the luminance information that the maximum value of the luminance value is not equal to or less than the threshold value (S503: No), the display control unit 12 gamma-corrects the video data of the display program using the HLG gamma curve to perform the display control signal. Is generated (S504). The HLG gamma curve used for the gamma correction in this case has not been gain-corrected by the correction unit 17. The display control unit 12 displays the video of the program on the display unit 3 by outputting the generated display control signal to the display unit 3 (S505).

When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the threshold value (S503: Yes), the correction unit 17 executes the gain correction process (S506). The correction unit 17 generates a corrected HLG gamma curve by multiplying each value of the HLG gamma curve by a correction coefficient of 1 or more in the gain correction process. The display control unit 12 generates a display control signal by gamma-correcting the video data of the display program using the corrected HLG gamma curve (S507). Then, the display control unit 12 displays the video of the program on the display unit 3 by outputting the generated display control signal to the display unit 3 (S505).

In this way, the video processing device 1 and the television receiver 10 of the first embodiment perform a determination process for determining whether or not the video system of the displayed program is the conversion HLG system. Then, when the video system of the displayed program is the conversion HLG system, the gain correction process for increasing each value of the HLG gamma curve is executed. As a result, it is possible to prevent the converted HLG video, which is a display program, from being displayed darker than the pure 4K video. Further, when the video system of the displayed program is the pure 4K system, the gain correction process is not executed, so that the saturation of the luminance level (so-called white area) is suppressed.

(Second Embodiment)
In the first embodiment, as described in Non-Patent Document 1, a case where a 100% SDR signal is assigned to a 75% HLG signal level has been described. That is, in the first embodiment, 100% SDR signal is assigned to the 75% HLG signal level regardless of the genre of the program. In the second embodiment, the case where the HLG signal level to which the 100% SDR signal is assigned differs depending on the genre of the program will be described.

In the second embodiment, the HLG signal level to which the 100% SDR signal is assigned differs depending on the genre of the program. For example, in the movie program, the 100% SDR signal is assigned to the 75% HLG signal level. It is assumed that 100% SDR signal is assigned to 90% HLG signal level for sports programs, and 100% SDR signal is assigned to 80% HLG signal level for non-movie and sports programs.

An operation example of the video processing device 1 and the television receiver 10 of the second embodiment will be described with reference to FIG.

FIG. 6 is an operation flowchart of the video processing device and the television receiver according to the second embodiment.

In S601, the receiving unit 2 receives the television broadcast (new 4K8K satellite broadcast) and outputs the data corresponding to the selected channel to the video processing device 1. Here, it is assumed that the channel corresponding to the 4K program is selected.

In S602, the luminance information acquisition unit 14 acquires the luminance information indicating the luminance value of each pixel of the video of the display program from the video data of the display program. Specifically, for example, the luminance information acquisition unit 14 acquires the luminance data (Y) indicating the luminance of each pixel of the video of the display program included in the video data having a predetermined time length as the luminance information.

In S603, the program guide generation unit 15 acquires the program information and generates an electronic program guide (EPG) based on the program information.

In S604 to S608, the determination unit 16 performs a determination process of determining the video system of the displayed program based on the luminance information acquired in S602 and the program information acquired in S603. Hereinafter, the details of the determination processing (S604 to S608) will be described.

In S604, the determination unit 16 determines whether or not the genre of the displayed program is a movie based on the program information acquired in S603. Specifically, for example, the determination unit 16 determines whether or not the genre of the displayed program is a movie based on the genre information included in the electronic program guide. When the genre information included in the electronic program guide is "movie", the determination unit 16 determines that the genre of the displayed program is a movie, and the control proceeds to S607. If the genre information included in the electronic program guide is not "movie", the determination unit 16 determines that the genre of the displayed program is not a movie, and the control proceeds to S605.

In S605, the determination unit 16 determines whether or not the genre of the displayed program is sports based on the program information acquired in S603. Specifically, for example, the determination unit 16 determines whether or not the genre of the displayed program is sports based on the genre information included in the electronic program guide. When the genre information included in the electronic program guide is "sports", the determination unit 16 determines that the genre of the displayed program is sports, and the control proceeds to S608. When the genre information included in the electronic program guide is not "sports", the determination unit 16 determines that the genre of the displayed program is not sports, and the control proceeds to S606.

In S606, the determination unit 16 determines whether or not the maximum value of the luminance value is equal to or less than the first threshold value in the luminance information acquired in S602. For example, in the second embodiment, programs other than movies and sports have 100% SDR signals assigned to 80% HLG signal levels, which corresponds to 80% of the maximum luminance value of 235 in the pure 4K system. 188 is used as the first threshold. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the first threshold value (S606: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S609. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the first threshold value (S606: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S611.

In S607, the determination unit 16 determines whether or not the maximum value of the brightness value is equal to or less than the second threshold value in the brightness information acquired in S602. For example, in the second embodiment, since the movie program has 100% SDR signal assigned to the 75% HLG signal level, 176 corresponding to 75% of the maximum luminance value 235 in the pure 4K system is set. Used as a threshold of 2. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the second threshold value (S607: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S609. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the second threshold value (S607: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S611.

In S608, the determination unit 16 determines whether or not the maximum value of the brightness value is equal to or less than the third threshold value in the brightness information acquired in S602. For example, in the second embodiment, since the sports program has 100% SDR signal assigned to the 90% HLG signal level, 211 corresponding to 90% of the maximum luminance value 235 in the pure 4K system is set. It is used as a threshold value of 3. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the third threshold value (S608: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S609. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the third threshold value (S608: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S611.

In S609, the correction unit 17 executes the gain correction process. The correction unit 17 generates a corrected HLG gamma curve by multiplying each value of the HLG gamma curve by a correction coefficient of 1 or more in the gain correction process.

In S610, the display control unit 12 generates a display control signal by gamma-correcting the video data of the display program using the corrected HLG gamma curve.

In S611, the display control unit 12 generates a display control signal by gamma-correcting the video data of the display program using the HLG gamma curve.

In S612, the display control unit 12 displays the video of the program on the display unit 3 by outputting the generated display control signal to the display unit 3.

The first to third threshold values used in each of S606 to S608 may be larger than the above-mentioned values in consideration of the case where the pre-conversion video contains super white.

In this way, the video processing device 1 and the television receiver 10 of the second embodiment perform a determination process for determining whether or not the video system of the displayed program is the conversion HLG system. Then, when the video system of the displayed program is the conversion HLG system, the gain correction process for increasing each value of the HLG gamma curve is executed. As a result, it is possible to prevent the converted HLG video, which is a display program, from being displayed darker than the pure 4K video. Further, when the video system of the displayed program is the pure 4K system, the gain correction process is not executed, so that the saturation of the luminance level (so-called white area) is suppressed. In the video processing device 1 and the television receiver 10 of the second embodiment, the video system is the conversion HLG system even when the HLG signal level to which the 100% SDR signal is assigned differs depending on the genre of the program. Can be determined

(Third Embodiment)
In the first embodiment, as described in Non-Patent Document 1, a case where a 100% SDR signal is assigned to a 75% HLG signal level has been described. That is, in the first embodiment, 100% SDR signal is assigned to the 75% HLG signal level regardless of the time of day. In the third embodiment, the case where the HLG signal level to which the 100% SDR signal is assigned differs depending on the time will be described.

In the third embodiment, the HLG signal level to which the 100% SDR signal is assigned differs depending on the broadcast time of the program. For example, the program broadcast between 6:00 and 18:00 has 90% SDR signal. Programs that are assigned to the% HLG signal level and broadcast between 5:30 and 6:00 or between 18:00 and 18:30 have 100% SDR signal assigned to the 80% HLG signal level and 18:30 to 5 It is assumed that a program broadcast during 30 minutes has a 100% SDR signal assigned to a 75% HLG signal level.

An operation example of the video processing device 1 and the television receiver 10 of the third embodiment will be described with reference to FIG. 7.

FIG. 7 is an operation flowchart of the video processing device and the television receiver according to the third embodiment.

In S701, the receiving unit 2 receives the television broadcast (new 4K8K satellite broadcast) and outputs the data corresponding to the selected channel to the video processing device 1. Here, it is assumed that the channel corresponding to the 4K program is selected.

In S702, the luminance information acquisition unit 14 acquires the luminance information indicating the luminance value of each pixel of the video of the display program from the video data of the display program. Specifically, for example, the luminance information acquisition unit 14 acquires the luminance data (Y) indicating the luminance of each pixel of the video of the display program included in the video data having a predetermined time length as the luminance information.

In S703, the determination unit 16 acquires the current time. The determination unit 16 acquires the current time from, for example, the received television broadcast. Further, the determination unit 16 may acquire the current time from the server through, for example, a clock (not shown) of the television receiver or a telecommunication line such as the Internet.

In S704 to S708, the determination unit 16 performs determination processing for determining the video system of the displayed program based on the luminance information acquired in S702 and the current time acquired in S703. Hereinafter, the details of the determination processing (S704 to S708) will be described.

In S704, the determination unit 16 determines whether or not the current time is between 6:00 and 18:00 based on the current time acquired in S703. If it is determined that the current time is between 6:00 and 18:00, control proceeds to S707. If it is determined that the current time is not between 6:00 and 18:00, control proceeds to S705.

In S705, the determination unit 16 determines whether or not the current time is between 5:30 and 6:00 or between 18:00 and 18:30 based on the program information acquired in S603. If it is determined that the current time is between 5:30 and 6:00 or between 18:00 and 18:30, control proceeds to S708. If it is determined that the current time is not between 5:30 and 6:00 or between 18:00 and 18:30, control proceeds to S706.

In S706, the determination unit 16 determines whether or not the maximum value of the luminance value is equal to or less than the fourth threshold value in the luminance information acquired in S702. For example, in the third embodiment, the program broadcast between 18:30 and 5:30 has a 100% SDR signal assigned to the 75% HLG signal level, so that the brightness value in the pure 4K system is used. 176, which corresponds to 75% of the maximum value of 235, is used as the fourth threshold value. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the fourth threshold value (S706: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S709. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the fourth threshold value (S706: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S711.

In S707, the determination unit 16 determines whether or not the maximum value of the luminance value is equal to or less than the fifth threshold value in the luminance information acquired in S702. For example, in the third embodiment, the program broadcast between 6:00 and 18:00 has a 100% SDR signal assigned to the 90% HLG signal level, so that the maximum brightness value of 235 in the pure 4K system is set. 211 corresponding to 90% is used as the fifth threshold. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the fifth threshold value (S707: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S709. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the fifth threshold value (S707: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S711.

In S708, the determination unit 16 determines whether or not the maximum value of the luminance value is equal to or less than the sixth threshold value in the luminance information acquired in S602. For example, in the third embodiment, a program broadcast between 5:30 and 6:00 or between 18:00 and 18:30 has 100% SDR signal assigned to the 80% HLG signal level. 188, which corresponds to 80% of the maximum value 235 of the brightness value in the pure 4K method, is used as the sixth threshold value. When it is determined in the luminance information that the maximum value of the luminance value is equal to or less than the sixth threshold value (S708: Yes), the determination unit 16 determines that the video system of the displayed program is the conversion HLG system, and the control is S709. Proceed to. When it is determined that the maximum value of the luminance value is not equal to or less than the sixth threshold value (S708: No), the determination unit 16 determines that the video system of the displayed program is not the conversion HLG system (that is, the pure 4K system) and controls it. Proceeds to S711.

Since the respective processes of S709 to S712 are the same as the respective processes of S609 to S612, the description thereof will be omitted.

The fourth to sixth threshold values used in each of S706 to S708 may be larger than the above-mentioned values in consideration of the case where the pre-conversion video contains super white.

In this way, the video processing device 1 and the television receiver 10 of the third embodiment perform a determination process for determining whether or not the video system of the displayed program is the conversion HLG system. Then, when the video system of the displayed program is the conversion HLG system, the gain correction process for increasing each value of the HLG gamma curve is executed. As a result, it is possible to prevent the converted HLG video, which is a display program, from being displayed darker than the pure 4K video. Further, when the video system of the displayed program is the pure 4K system, the gain correction process is not executed, so that the saturation of the luminance level (so-called white area) is suppressed. In the video processing device 1 and the television receiver 10 of the third embodiment, even if the HLG signal level to which the 100% SDR signal is assigned differs depending on the broadcast time of the program, the video system is the conversion HLG system. It is possible to determine whether or not there is.

The same functions as the video processing apparatus 1 of the first to third embodiments may be embodied by a video processing method, a (computer) program, a non-temporary recording medium on which the program is recorded, or the like.

The video processing method includes a luminance information acquisition process, a determination process, and a gain correction process. In the luminance information acquisition process, the luminance information of the video of the program in the television broadcast received by the receiving unit 2 is acquired. In the determination process, the video system of the program in the television broadcast received by the receiving unit 2 is determined based on the luminance information of the program. In the gain correction process, the brightness level when the program is displayed on the display unit 3 is increased. The video system includes a first video system having a first resolution and a second video system in which a pre-conversion video having a second resolution lower than the first resolution is expanded and converted in resolution and dynamic range. The gain correction process is executed when it is determined in the determination process that the program is the second video system.

The program causes the computer system to execute the video processing method.

(Modification example)
In the above example, the case where the video processing device 1 is applied to the television receiver 10 has been described as an example, but the video processing device 1 can be applied to a mobile terminal such as a set-top box, a personal computer, or a smartphone. be.

1 Video processing device 10 TV receiver 11 Separation unit 12 Display control unit 13 Audio control unit 14 Luminance information generation unit 15 Program guide generation unit 16 Judgment unit 17 Correction unit 2 Receiver 3 Display unit 4 Speaker

Claims (8)

A brightness information acquisition unit that acquires brightness information of a program image in a television broadcast received by the receiver, and a brightness information acquisition unit.
A determination unit that determines the video system of the program based on the luminance information,
A correction unit that performs gain correction processing that increases the brightness level when the program is displayed on the display unit is provided.
The video system is
The first video system, which is the first resolution,
The pre-conversion video having a second resolution lower than the first resolution is included in the second video system in which the resolution and the dynamic range are expanded and converted.
When the determination unit determines that the program is the second video system, the correction unit executes the gain correction process.
Video processing equipment. The video processing device according to claim 1, wherein the determination unit determines that the program is the second video system when the maximum value of the brightness value is equal to or less than a threshold value in the brightness information. In the pre-conversion video, the signal level corresponding to the reference white is the first level.
In the second video system, the signal level corresponding to the reference white is the second level lower than the first level.
In the correction process, the correction unit multiplies the value of the gamma curve by using the value of the ratio of the ratio of the first level to the second level as a correction coefficient.
The video processing apparatus according to claim 1 or 2. The dynamic range of the pre-conversion video is SDR.
The second video system is an HLG system, and is
The first level is 100%
The second level is 75%.
The video processing apparatus according to claim 3. The video processing device according to claim 1 or 2, wherein the determination unit determines the video system of the program based on the genre of the program and the brightness information. The video processing device according to claim 1 or 2, wherein the determination unit determines the video system of the program based on the current time and the luminance information. The video processing device according to any one of claims 1 to 6.
With the receiver
The display unit is provided.
TV receiver. It is a program for causing a computer system to execute a luminance information acquisition process, a determination process, and a gain correction process.
In the luminance information acquisition process, the luminance information of the video of the program in the television broadcast received by the receiving unit is acquired.
In the determination process, the video system of the program is determined based on the luminance information.
In the gain correction process, the brightness level when the program is displayed on the display unit is increased.
The video system is
The first video system, which is the first resolution,
The pre-conversion video having a second resolution lower than the first resolution is included in the second video system in which the resolution and the dynamic range are expanded and converted.
The gain correction process is executed when the determination process determines that the program is the second video system.
program.

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