JP2013211799A - Video processing device, video processing method, and video processing program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress black crushing in a dark part.SOLUTION: A video processing device has first extraction means, generation means, synthesis means, and correction means. The first extraction means extracts distribution information on pixels for each luminance, from image information. The generation means, when the image information includes pixels having a predetermined luminance or lower, generates second distribution information in which the number of pixels having a luminance within a predetermined range is added on the basis of the luminance of the pixels. The synthesis means synthesizes the second distribution information generated by the generation means on first distribution information extracted by the first extraction means. The correction means, on the basis of the distribution information synthesized by the synthesis means, performs tone correction to the image information.

Description

  Embodiments described herein relate generally to a video processing apparatus, a video processing method, and a video processing program.

  Conventionally, various image processing has been performed on video signals. As an image processing technique, for example, there is a technique for performing gradation correction of the image information.

  When tone correction is performed on the entire screen area displayed by the video signal, when local information is concentrated on a specific luminance level, there is a problem that the luminance gradient of the concentrated area becomes steep. . For this reason, a technique has been proposed in which gradation correction is flexibly changed by providing conversion parameters that can be specified for each luminance level.

JP 2007-36946 A

  However, in the prior art, tone correction can be flexibly changed, but it is necessary to set conversion parameters in accordance with image information. For this reason, it is difficult to deal with blackout suppression that the user does not recognize as being different.

  The present invention has been made in view of the above, and an object thereof is to provide a video processing device, a video processing method, and a video processing program that suppress blackout in a dark part.

  The video processing apparatus according to the embodiment includes a first extraction unit, a generation unit, a synthesis unit, and a correction unit. The first extraction unit extracts pixel distribution information for each luminance from the image information. The generation unit generates second distribution information in which the number of pixels having a luminance within a predetermined range is increased with reference to the luminance of the pixel when the image information includes a pixel having a luminance equal to or lower than the predetermined luminance. The synthesizing unit synthesizes the second distribution information generated by the generating unit with the first distribution information extracted by the first extracting unit. The correcting unit performs gradation correction on the image information based on the distribution information combined by the combining unit.

FIG. 1 is a diagram illustrating a hardware configuration of the television broadcast receiving apparatus according to the first embodiment. FIG. 2 is a diagram illustrating a region to be extracted from a histogram generated by the distribution extraction unit according to the first embodiment. FIG. 3 is a diagram illustrating transitions of luminance histograms until they are combined by the combining unit according to the first embodiment. FIG. 4 is a diagram illustrating a tone curve generated by the tone curve generation unit according to the first embodiment. FIG. 5 is a diagram illustrating an example of a video setting menu displayed by the television broadcast receiver according to the first embodiment. FIG. 6 is a diagram illustrating an example of a setting menu of the image realizer displayed by the television broadcast receiver according to the first embodiment. FIG. 7 is a diagram illustrating an example of a color gradation correction selection menu displayed by the television broadcast receiving apparatus according to the first embodiment. FIG. 8 is a flowchart showing a procedure of processing until gradation correction is performed in the television broadcast receiving apparatus according to the first embodiment. FIG. 9 is a diagram illustrating an example of a result of gradation correction performed by the television broadcast receiver according to the first embodiment.

  FIG. 1 is a diagram illustrating a hardware configuration of the television broadcast receiving apparatus 100 according to the first embodiment. FIG. 1 is a block diagram showing a main signal processing system of the television broadcast receiving apparatus 100 described above.

  As shown in FIG. 1, an antenna 101 for receiving a terrestrial broadcast is connected to the input side thereof, and the television broadcast receiving device 100 is directly connected to an external display device or audio output device, and the user can This apparatus can be operated via an operation unit (not shown) provided in the broadcast receiving apparatus 100, and can also be operated via a remote controller 180 by infrared communication.

  The television broadcast receiving apparatus 100 displays a broadcast program by decoding the received terrestrial digital television broadcast signal, and the user can view the received broadcast program. In addition, broadcast programs can be viewed using an external display device or audio output device, and received broadcast programs can be recorded.

  1 may be configured to include a plurality of receiving circuits such as tuners for receiving broadcast waves.

  The terrestrial digital television broadcast signal received by the terrestrial broadcast receiving antenna 101 is supplied to the terrestrial digital broadcast tuner 103 via the input terminal 102.

  Tuner 103 selects a broadcast signal of a desired channel based on a control signal from processing unit 105, and outputs the selected broadcast signal to demodulator 104a.

  The demodulator 104a demodulates the broadcast signal selected by the tuner 103 based on the control signal from the processing unit 105, obtains a transport stream including a desired program, and outputs the transport stream to the decoder 104b.

  The decoder 104b performs a TS decoding process on the transport stream (TS) multiplexed signal according to the control signal from the processing unit 105, and depackets the digital video signal and audio signal of the desired program. (Packetized Elementary Stream) is output to the STD buffer in the signal processing unit 106. In addition, the decoder 104 b outputs the section information transmitted by digital broadcasting to the section unit 132 in the signal processing unit 106.

  Here, the signal processing unit 106 includes a decoder 131, a section unit 132, and an extraction unit 133, and processes an input signal.

  The decoder 131 selectively performs predetermined digital signal processing on the digital video signal and audio signal supplied from the decoder 104 b when viewing the television, and outputs the result to the graphic processing unit 107 and the audio processing unit 108. On the other hand, at the time of program recording, a signal obtained by selectively performing predetermined digital signal processing on the digital video signal and audio signal supplied from the decoder 104b is sent via a processing unit 105 to a recording device (for example, an HDD). ) Record at 170.

  In addition, the decoder 131 performs predetermined digital signal processing on the recorded program data read from the recording device (for example, HDD) 170 via the processing unit 105 when the recorded program is reproduced, and performs the graphic processing unit 107 and the audio. The data is output to the processing unit 108.

  The extraction unit 133 extracts luminance distribution information (histogram) on the screen displayed by the video signal from the video signal after the digital signal processing. Then, the luminance distribution information extracted by the extraction unit 133 is output to the display control unit 150 of the processing unit 105.

  The processing unit 105 includes various data (such as key information for B-CAS descrambling), electronic program guide (EPG) information, program attribute information (program genre, etc.) for acquiring a program from the signal processing unit 106. Subtitle information and the like (service information, SI and PSI) are input. The processing unit 105 performs image generation processing to display EPG and subtitles from the input information, and outputs the generated image information to the graphic processing unit 107.

  In addition, the processing unit 105 has a function of controlling program recording and program reservation recording. When a program reservation is accepted, the processing unit 105 displays electronic program guide (EPG) information on the display device 111, and the operation unit 120 or the remote controller 180 is displayed. The reservation content is set in a predetermined storage means by user input. Then, the tuner 103, the demodulator 104a, the decoder 104b, and the signal processing unit 106 are controlled to record the reserved program at the set time.

  The section unit 132 includes various data for acquiring a program, electronic program guide (EPG) information, program attribute information (program genre, etc.), subtitle information, etc. (service information) from the section information input from the decoder 104b. , SI and PSI) are output to the processing unit 105.

  The graphic processing unit 107 includes (1) a digital video signal supplied from the decoder 131 in the signal processing unit 106, (2) an OSD signal generated by an OSD (On Screen Display) signal generation unit 109, and (3 And (4) a function of synthesizing the EPG and caption signal generated by the processing unit 105 and outputting the image information to the video processing unit 110. Further, when displaying a caption by caption broadcasting, the graphic processing unit 107 performs a process of superimposing the caption information on the video signal based on the caption information controlled by the processing unit 105.

  The digital video signal output from the graphic processing unit 107 is supplied to the video processing unit 110. The video processing unit 110 converts the input digital video signal into an analog video signal that can be displayed on the display device 111, and then outputs the analog video signal to the display device 111 for video display. In addition, a video signal in a format that can be displayed on the display device can be output to an external display device (not shown) via the output terminal 112 and displayed.

  The audio processing unit 108 converts the input digital audio signal into an analog audio signal that can be reproduced by the audio output device 113, and then outputs the analog audio signal to the audio output device 113 to reproduce the audio. It is also possible to output an audio signal in a format reproducible by the audio output device to an external audio output device (not shown) via the output terminal 114 for audio reproduction.

  Here, in the television broadcast receiving apparatus 100, all the operations including the above-described various receiving operations are comprehensively controlled by the processing unit 105. The processing unit 105 includes a CPU (Central Processing Unit) or the like and receives operation information from the operation unit 120 or receives operation information sent from the remote controller 180 via the light receiving unit 121. Each unit is controlled so that the operation content (for example, channel switching operation, etc.) is reflected.

  In this case, the processing unit 105 mainly includes a ROM (Read Only Memory) 105a that stores a control program executed by the CPU, a RAM (Random Access Memory) 105b that provides a work area to the CPU, and various setting information. And a non-volatile memory 105c such as a flash memory in which control information and program information are stored.

  In addition, the processing unit 105 includes a display control unit 150. As shown in FIG. 1, the display control unit 150 includes a distribution extraction unit 151, an adjustment unit 152, a synthesis unit 153, and a tone curve generation unit 154.

  In addition, the video processing unit 110 includes a correction unit 161. The correction unit 161 corrects the screen information included in the digital video signal according to the tone curve generated by the tone curve generation unit 154 of the display control unit 150. When performing correction according to the tone curve, the correction unit 161 refers to the data conversion table 105d stored in the nonvolatile memory 105c. The correction unit 161 can correct the video signal according to the tone curve by referring to the data conversion table.

  The television broadcast receiving apparatus 100 according to the present embodiment has the above-described configuration, acquires a histogram for the luminance of the input video signal, and performs tone correction based on the histogram. By the way, in a specific video signal, if gradation correction is performed based on a conventionally used rule, there is a possibility that a subtle color difference in a dark part may be lost.

  Therefore, the television broadcast receiving apparatus 100 according to the present embodiment measures a dark area of the image information displayed by the video signal, and when the area is colored, the floor is prevented from being blacked out. Tonal correction was performed. By performing the gradation correction, it is possible to display the difference in the dark area so as to be easily recognized by the user.

  The distribution extraction unit 151 extracts a luminance histogram of pixels having a saturation equal to or higher than a predetermined value from image information displayed according to the digital video signal. Note that the predetermined value is set to an appropriate value according to the embodiment.

  Next, in the present embodiment, a pixel from which a luminance histogram is extracted will be described. In the present embodiment, an example in which a luminance histogram is used as the brightness distribution information to be extracted will be described. However, elements other than the luminance may be used as long as the contrast of the screen information can be recognized.

  FIG. 2 is a diagram showing a region from which a histogram generated by the distribution extraction unit 151 is to be extracted. The example illustrated in FIG. 2 indicates that the histogram extraction target is the color region 201 in the color space represented by the luminance signal Y and the two color difference signals (Cb, Cr). In the three-dimensional coordinates shown in FIG. 2, different axes are assigned to the luminance signal Y and the two color difference signals (Cb, Cr). A color area 201 is a cylindrical area along the Y (luminance) axis, and indicates a color area in which the saturation is equal to or greater than a predetermined value. That is, it means that a portion where the color difference signals Cb / Cr intersect is colorless, and a pixel with low saturation is excluded from a target to be extracted as a luminance histogram. The reason why the pixels with low saturation are excluded from the extraction target of the luminance histogram is that the pixels with low saturation are likely to be noise because they are highly likely to be noise. The reason for this is that it is a dark area with a deep color. By excluding pixels with low saturation from the extraction target of the histogram, it is possible to suppress enhancement of pixels that are noise.

  When the luminance histogram extracted by the distribution extraction unit 151 includes a pixel that is equal to or lower than the predetermined luminance, the adjustment unit 152 determines that the luminance histogram extracted from the luminance histogram is within a predetermined range based on the luminance of the pixel. A brightness histogram is generated by increasing the number of brightness pixels.

  The combining unit 153 combines the luminance histogram generated by the adjusting unit 152 with the luminance histogram extracted by the extracting unit 133. In the present embodiment, addition is used as a synthesis method. In the present embodiment, the synthesis method is not limited to addition, and other methods such as multiplication may be used.

FIG. 3 is a diagram illustrating a transition of a histogram of luminance until synthesis is performed by the synthesis unit 153. In the present embodiment, the target for gradation correction is the luminance b ₁ or less. Thus, in the present embodiment, it is possible to suppress blackout by performing gradation correction on luminance b ₁ or lower. Note that the gradation correction for luminance b ₁ or higher is performed as usual, and the description thereof is omitted in this embodiment.

  3 is a luminance histogram extracted by the extraction unit 133. FIG. In the histogram, the horizontal axis is the luminance, and the vertical axis is the number of pixels. The vertical axis may be considered as the area for each luminance on the display screen instead of the number of pixels. Then, (2) in FIG. 3 is a histogram of luminance extracted by the distribution extraction unit 151 by pixels having a saturation greater than or equal to a predetermined value. In the present embodiment, gradation correction is performed for an element of which saturation is equal to or greater than a predetermined value, in other words, “brightness having a color element”. Therefore, in (2) of FIG. 3, an element of “luminance with color elements” is extracted.

(3) in FIG. 3 is a luminance histogram generated by the adjustment unit 152. As shown in (3) of FIG. 3, the frequency is adjusted to be the same for two adjacent light and dark sections with reference to the luminance level at which the pixel is detected. In other words, when the luminance histogram extracted by the distribution extraction unit 151 includes pixels with luminance b ₁ or lower, the adjustment unit 152 has the same number of pixels as the luminance level pixels with luminance b ₁ or lower. Then, the brightness level is adjusted so that it is included in the brightness levels of the two bright and dark sections, and a brightness histogram is generated. In the example shown in FIG. 3, the range to be adjusted for the brightness level is set to two sections for light and dark, but an appropriate range is set according to the embodiment. Further, in this embodiment, correction is performed for each range of light and dark. However, only a predetermined range may be corrected for the darker one or a predetermined range for the brighter one from the luminance from which the pixels are extracted.

  Further, the range to be adjusted may be varied depending on the number of detected pixels. For example, in the example in which the frequency “10” indicating the extracted pixel is generated only in the luminance level “5”, the area to which the same frequency is allocated is ± 2. Thereby, the adjustment part 152 adjusts so that frequency 10 may be allocated with respect to each of the luminance levels 3-7. As a method for determining the designated area, in this embodiment, a lookup table (LUT) is used so that each level can be set independently. It should be noted that a range in which it is determined that it is not necessary to perform allocation may be set so that the allocation is not performed.

  3 (4) shows a luminance histogram after being synthesized by the synthesizing unit 153. FIG. In the example shown in (4) of FIG. 3, the luminance histogram adjusted by the adjusting unit 152 is superimposed on the luminance histogram extracted by the extracting unit 133. Thus, in this embodiment, addition is performed for each element of luminance.

  In addition, in the addition process, when the differential gain is increased particularly when concentrated in a dark part, the noise component may be improved together, resulting in an unpleasant image. Therefore, in this embodiment, a different weighting coefficient may be used for each luminance level when performing addition.

  The synthesizing unit 153 according to the present embodiment multiplies the luminance histogram ((3) in FIG. 3) generated by the adjusting unit 152 by a different weighting coefficient for each level, and then extracts the luminance extracted by the extracting unit 133 Is added to the histogram ((1) in FIG. 3). As the weighting, the intermediate luminance component having the highest effect is increased in weight, and the effect is reduced by decreasing the weighting in the vicinity of the pedestal level where the effect of the color component is reduced. As a result, it is possible to clarify the brightness and darkness of the intermediate luminance component and to smoothly connect the levels.

  The tone curve generation unit 154 generates a tone curve for performing tone correction on the image information included in the video signal based on the luminance histogram synthesized by the synthesis unit 153.

  FIG. 4 is a diagram showing a tone curve generated by the tone curve generation unit 154. As shown in FIG. In the tone curve shown in FIG. 4, the horizontal axis is input luminance, and the vertical axis is output luminance. In FIG. 4, the tone curve generation unit 154 performs gain processing (multiplies each frequency), thereby enabling control of the gradient of the differential gain across the corresponding level in the output tone curve.

  Any method may be used as a tone curve generation method. For example, the frequency data for each level in the luminance histogram after the synthesis may be cumulatively added. As a result, the slope becomes large at the level where the frequencies are dense (a lot of information), so that the differential gain when performing the gradation correction increases, and the gradation correction is performed at a level where the frequency is sparse (the information is small). The differential gain is reduced.

  Then, the tone curve generation unit 154 compares the maximum value generated at the end of the generated tone curve with the maximum value that can be received by the video processing circuit, and after performing the process of matching by performing gain control, the tone curve Is output to the video processing unit 110.

  Then, the correction unit 161 performs tone correction according to the tone curve generated by the tone curve generation unit 154. In other words, gradation correction is performed on the digital image information included in the video signal based on the luminance histogram synthesized by the synthesis unit 153.

  In the gradation correction processing by the correction unit 161, the image of each brightness derived from the brightness distribution of the digital image information of the video signal by performing gradation correction according to the tone curve generated by the tone curve generation unit 154. According to the area, processing is performed so that each brightness is at an optimum level.

  In the present embodiment, by creating a tone curve using the synthesized luminance histogram, an effect of increasing the differential gain can be generated so that pixels having saturation in the dark region do not be blacked out. Thereby, the user can recognize the color of the pixel.

  The video processing unit 110 outputs the video signal whose gradation has been corrected by the correction unit 161 to the display device 111. Thereby, the display device 111 displays a display screen based on the video signal output from the video processing unit 110.

  Further, the video processing unit 110 can superimpose and output various window information on the video signal. In the present embodiment, window information for setting gradation correction can be displayed.

  Next, operations until the gradation correction of the television broadcast receiving apparatus 100 according to the present embodiment is started will be described.

  FIG. 5 is a diagram illustrating an example of a video setting menu displayed by the television broadcast receiving apparatus 100. The video setting menu 501 shown in FIG. 5 may be displayed by pressing a predetermined button provided on the remote controller 180, or may be displayed by accepting selection of a video setting item from the main menu. good. In the present embodiment, when the remote controller 180 accepts selection of the item 502 indicated as the image realizer, the video setting menu 501 transitions to the image realizer setting menu.

  FIG. 6 is a diagram showing an example of the setting menu of the image realizer displayed by the television broadcast receiving apparatus 100. In the image realizer setting menu 601 shown in FIG. 6, graphic NR, color gradation correction 602, and color texture correction are displayed as selectable items. In the present embodiment, when the selection of the item 602 indicated as color gradation correction is accepted, the display shifts to a color gradation correction selection menu.

  FIG. 7 is a diagram illustrating an example of a selection menu for color gradation correction displayed by the television broadcast receiving apparatus 100. In the color gradation correction selection menu 701 shown in FIG. 7, “ON” 702 and “OFF” are displayed as selectable items. In the present embodiment, the above-described gradation correction is performed when ON 702 is selected.

  Next, processing until the gradation correction is performed in the television broadcast receiving apparatus 100 according to the present embodiment will be described. FIG. 8 is a flowchart showing a procedure of the above-described processing in the television broadcast receiving apparatus 100 according to the present embodiment.

  First, the video processing unit 110 displays a video setting window as shown in FIG. 5 in accordance with an operation from the user (step S801).

  Then, the processing unit 105 receives the selection of the image realizer performed by the remote controller 180 via the light receiving unit 121 (step S802).

  Thereafter, the video processing unit 110 displays an image realizer setting window as shown in FIG. 6 (step S803).

  Next, the processing unit 105 receives the selection of color gradation correction performed by the remote controller 180 via the light receiving unit 121 (step S804).

  The video processing unit 110 displays a color gradation correction setting window as shown in FIG. 7 (step S805).

  Next, the processing unit 105 receives the “ON” selection performed by the remote controller 180 via the light receiving unit 121 (step S806).

  Accordingly, the extraction unit 133 extracts a luminance histogram from the video signal (step S807). Note that the extracted luminance histogram is extracted so that the correspondence with the color can be recognized. The extracted luminance histogram is output to the display control unit 150 together with the video signal.

  Then, the distribution extraction unit 151 extracts a luminance histogram from pixels whose saturation is equal to or less than a predetermined value from the video signal (step S808).

  Next, the adjustment unit 152 generates a luminance histogram adjusted to a predetermined luminance or less with respect to the luminance histogram extracted in step S808 (step S809).

  After that, the synthesizing unit 153 synthesizes the luminance histogram generated by the adjusting unit 152 with the luminance histogram extracted by the distribution extracting unit 151 (step S810).

  Then, the tone curve generation unit 154 generates a tone curve from the synthesized histogram (step S811).

  Thereafter, the correction unit 161 performs gradation correction on the screen information displayed as the digital video signal based on the generated tone curve (step S812). At that time, the correction unit 161 refers to the data conversion table 105d. Thereby, parameters for performing gradation correction based on the tone curve are set.

  Thereafter, the video processing unit 110 performs display on the display device 111 using the video signal on which the gradation correction has been performed (step S810).

  According to the above-described processing procedure, it is possible to adjust so that pixels with high saturation are not crushed in the dark area.

  In the conventional gradation correction processing, the brightness that is closest to the pedestal level in the video is detected by histogram determination, and the optimization processing is performed so that the detected brightness level becomes the blackest level of the output image. . In such gradation correction processing, if a color is added to the detected luminance level, the conventional gradation processing corrects it to the blackest level, and the output video loses color.

  FIG. 9 is a diagram illustrating an example of a result of gradation correction performed by the television broadcast receiving apparatus 100 according to the present embodiment. (1) in FIG. 9 is an example of a screen on which conventional gradation correction has been performed. In the screen example shown in (1) of FIG. 9, (especially in an animation), the hair colors of two people are drawn in different colors (for example, black and a non-black but highly saturated color). In this case, when the luminance level shows almost the same value, the black level has been corrected.

  In the present embodiment, in order to prevent the color from disappearing, when a dark portion having a luminance equal to or lower than a predetermined luminance is colored, the television broadcast receiving device 100 uses the luminance of the pixel having the color in the luminance histogram. The frequency is virtually allocated for a predetermined range based on the level. By performing tone correction after this processing, if the darkest part of the input video is colored, the output video will be shifted to the brighter direction without making that part the blackest level. . As a result, the process of preventing color collapse for the blackest level of the input video is performed. Therefore, as shown in (2) of FIG. 9, it is possible to display the hair color so that it is clearly different.

  In this way, it is possible to display to the user so that a minute color difference in the video signal can be recognized.

  In this embodiment, the case where the user selects to perform color gradation correction actively has been described. However, the selection is not limited to the case where the user selects, and it may be selected to automatically perform color gradation correction on the television broadcast receiving apparatus 100 side. For example, referring to meta information for each program in the EPG, it is determined whether or not the program is suitable for the gradation correction, and when it is determined that the program is appropriate for the gradation correction, the gradation is automatically set. You may set to correct | amend.

  Although this embodiment demonstrated the example using the television broadcast receiver 100, it is not restricted to the television broadcast receiver 100, You may apply to another apparatus. For example, the present invention may be applied to a portable device such as a tablet terminal, or may be applied to a content recording device connected to the television broadcast receiving device 100. Any device capable of outputting or displaying video information as described above may be used.

  As described above, according to the first embodiment, the contrast is enlarged so that the difference is clear about the highly saturated pixels in the dark region. Thus, by improving the contrast for the dark area, it is possible to display so that the color difference that the user has not recognized can be recognized.

  According to the first embodiment, when there is a slight difference in brightness in the dark area in the video, gradation correction is performed to intentionally enlarge this difference. In this way, differences that would normally be buried can be highlighted.

  According to the above-described embodiment, even in the case where the color crushing phenomenon occurs in the dark portion in the gradation correction processing performed using the conventional luminance-only element, the above-described processing enables the color to be drawn in the dark portion. .

  Note that the display control program executed by the television broadcast receiving apparatus 100 of the present embodiment is provided by being incorporated in advance in a ROM or the like. In the present embodiment, the display control unit 150, the correction unit 161, and the video processing unit 110 are configured separately, but may be configured in the processing unit 105 collectively.

  The display control program executed by the television broadcast receiving apparatus 100 of the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, flexible disk (FD), CD-R, DVD (Digital Versatile Disk). ) Or the like may be recorded and provided on a computer-readable recording medium.

  Furthermore, the display control program executed by the television broadcast receiving apparatus 100 according to the present embodiment may be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network. good. Further, the display control program executed by the television broadcast receiving apparatus 100 of the present embodiment may be provided or distributed via a network such as the Internet.

  The display control program executed by the television broadcast receiving apparatus 100 according to the present embodiment has a module configuration including the above-described units. As actual hardware, a CPU (processor) reads the display control program from the ROM. As a result, the above-described units are loaded on the main storage device, and the above-described configuration is generated on the main storage device.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

  DESCRIPTION OF SYMBOLS 100 ... Television broadcasting receiver, 101 ... Antenna, 102 ... Input terminal, 103 ... Tuner, 104a ... Demodulator, 104b ... Decoder, 105 ... Decoder, 105a ... ROM, 105b ... RAM, 105c ... Non-volatile memory, 105d ... Data conversion table 106 ... Signal processing unit 107 ... Graphic processing unit 108 ... Audio processing unit 109 ... OSD signal generation unit 110 ... Video processing unit 111 ... Display device 112 ... Output terminal 113 ... Audio Output device 114... Output terminal 120 .. operation unit 121 .. light receiving unit 131... Decoder, 132 .. section unit, 133 .. extraction unit, 150 ... display control unit, 151 ... distribution extraction unit, 152. ... Synthesizer, 154 ... tone curve generator, 161 ... corrector, 180 ... remote controller

Claims (6)

First extraction means for extracting pixel distribution information for each luminance from the image information;
Generating means for generating second distribution information in which the number of pixels having a luminance within a predetermined range is increased with reference to the luminance of the pixel when the image information includes a pixel having a luminance equal to or lower than the predetermined luminance;
Combining means for combining the first distribution information extracted by the first extracting means with the second distribution information generated by the generating means;
Correction means for performing gradation correction on the image information based on the distribution information synthesized by the synthesis means;
A video processing apparatus comprising: A second extracting means for extracting luminance distribution information by pixels having a saturation equal to or higher than a predetermined value among the image information;
When the luminance distribution information extracted by the second extraction unit includes a pixel that is equal to or lower than the predetermined luminance, the generation unit includes a pixel within the predetermined range based on the luminance of the pixel. Generating second distribution information adjusted so that pixels of the luminance are included in the image information with respect to the luminance;
The video processing apparatus according to claim 1. When the generation unit includes pixels having the predetermined luminance or lower, the same number of pixels as the arbitrary luminance having the predetermined luminance or lower are within a predetermined range based on the arbitrary luminance. Generating second distribution information adjusted to have brightness;
The video processing apparatus according to claim 1 or 2. An output means for outputting a display screen capable of selecting whether or not to perform gradation correction;
Control means for accepting selection of whether or not to perform gradation correction;
The correction unit performs gradation correction on the image when receiving a selection to perform gradation correction;
The video processing apparatus according to claim 1. A video processing method executed by a video processing apparatus,
A first extracting unit that extracts pixel distribution information for each luminance from the image information;
When the image information includes a pixel having a luminance equal to or lower than a predetermined luminance, the generating means generates second distribution information in which the number of pixels having a luminance within a predetermined range is increased based on the luminance of the pixel. Generation step;
A synthesis step of synthesizing the second distribution information generated by the generation step with the first distribution information extracted by the first extraction step;
A correction step in which correction means performs gradation correction on the image information based on the distribution information combined in the combining step;
Video processing method. A first extraction step of extracting pixel distribution information for each luminance from the image information;
A generation step of generating second distribution information in which the number of pixels having a luminance within a predetermined range is increased based on the luminance of the pixel when the image information includes a pixel having a luminance equal to or lower than the predetermined luminance;
A synthesis step of synthesizing the second distribution information generated in the generation step with the first distribution information extracted in the first extraction step;
A correction step for performing gradation correction on the image information based on the distribution information synthesized by the synthesis step;
A video processing program for causing a computer to execute.

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