JP2022085651A - Display controller and method for controlling display - Google Patents

Abstract

To provide a technique that can easily grasp the relative position of a chromaticity in a color region.SOLUTION: A display controller includes: setting means for setting a color region; conversion means for converting a pixel value to a chromaticity; acquisition means for acquiring information on the relative position of the chromaticity to the color region on the basis of the color region and the chromaticity; control means for controlling the chromaticity to be displayed, the control means changing the display showing the chromaticity according to the information.SELECTED DRAWING: Figure 1

Description

The present invention relates to a display control device and a display control method.

In recent years, in addition to broadcasting that handles video with a resolution of 2K (2K broadcasting), there are increasing opportunities to produce video for broadcasting that handles video with a resolution of 4K (4K broadcasting). 2K broadcasting is available from ITU-R BT. The color gamut (709 color gamut) defined by 709 is adopted. 4K broadcasting has a wider color gamut than 709 color gamut so that it can handle a wider color gamut than 2K broadcasting. The color gamut (2020 color gamut) defined by 2020 is adopted.

When producing a video, the chromaticity of the video may be checked to check the vividness of the color, that is, whether the color gamut can be widely used. In addition, video content in the 2020 color gamut used for 4K broadcasting may be used for 2K broadcasting to produce video. At that time, a color outside the 709 color gamut that cannot be expressed in the 709 color gamut used in 2K broadcasting cannot be expressed as a correct color because it is clipped within the 709 color gamut, for example. As the chromaticity is farther from the 709 color gamut, the color changes significantly from the original image, so the chromaticity outside the 709 color gamut may be confirmed.

Functions for checking the chromaticity of an image include a chromaticity display function as shown in FIG. 10 and an out-of-gamut coloring display function (out-of-gamut warning function) as shown in FIGS. 11 (A) and 11 (B). There is.

The chromaticity display function shown in FIG. 10 is a function for plotting the chromaticity of an image on an xy chromaticity diagram. In the chromaticity display function shown in FIG. 10, the xy coordinate axis 1100, the image color gamut 1101, the reference color gamut 1102, the chromaticity 1103, and the white point 1104 are displayed. The xy coordinate axes 1100 are the x-axis and the y-axis indicating the range of 0 to 1, respectively. The image color gamut 1101 is a preset color gamut (image color gamut), which is the 2020 color gamut in FIG. The reference color gamut 1102 is a preset reference color gamut, which is 709 color gamut in FIG. In both the image color gamut 1101 and the reference color gamut 1102, the xy value corresponding to the maximum R value (G value and B value are zero), the xy value corresponding to the maximum G value (R value and B value are zero), and , The gamut of the triangle connecting the xy values corresponding to the maximum B value (R value and G value are zero). If the color gamut is different, the xy value corresponding to the RGB value is also different. The chromaticity 1103 is the chromaticity of one pixel of the image, and is plotted on the xy coordinates (xy value) obtained by converting the RGB value of the pixel based on the image color gamut. The white point 1104 is a chromaticity representing white color at a predetermined color temperature, and is a white point at a color temperature D65 in the 2020 color range in FIG.

The out-of-color coloring display function shown in FIGS. 11 (A) and 11 (B) is a function of coloring an area of the image whose chromaticity is outside the reference color range when displaying an image. In FIGS. 11A and 11B, it is assumed that the color gamut of the image is the 2020 color gamut and the reference color gamut is the 709 color gamut. FIG. 11A shows an image before coloring, assuming that the chromaticity of all pixels in the inner region 1200 of the central circle is within the 709 color range, and the chromaticity of all pixels in the outer region 1201 of the circle is outside the 709 color range. Suppose there is. 11 (B) shows the image after coloring with respect to the image of FIG. 11 (A). In the internal region 1202 of the central circle, the chromaticity before coloring (the chromaticity of the internal region 1200 in FIG. 11A) is within the 709 color range, so that the same gradation value as before coloring (the same floor as the internal region 1200). Pixels are displayed at (Measurement) (Maintenance of gradation value). In the outer region 1203 of the circle, the chromaticity before coloring (the chromaticity of the external region 1201 in FIG. 11A) is outside the 709 color range, so that the predetermined gradation value is used regardless of the gradation value before coloring. Pixels are displayed (replacement of gradation values). For example, in the external region 1203, pixels are displayed with RGB values (R value, G value, B value) = (1023, 0, 0).

In Patent Document 1, in order to easily grasp whether or not the chromaticity of an image is outside the standard color range in the chromaticity display function, the chromaticity is displayed according to whether or not the chromaticity is outside the standard color range. Techniques for changing colors are described. Patent Document 2 describes a technique for changing the gradation value of a color indicating that the color is out of the color range according to the luminance setting value of the display device in the out-of-color range coloring display function.

International Publication No. 2008/078358 Japanese Unexamined Patent Publication No. 2019-35923

However, even if the conventional function for confirming the chromaticity is used, the relative position of the chromaticity with respect to the color gamut cannot be easily grasped.

For example, even if the conventional chromaticity display function is used, the chromaticity, the white point, the edge of the color gamut, etc. can be grasped in order to grasp how far the chromaticity is from the white point and how close it is to the color gamut. The position (coordinates) of must be visually confirmed. Therefore, it is difficult to know whether the color gamut can be used widely.

By using the technique described in Patent Document 1 and the technique described in Patent Document 2, it is possible to easily grasp whether or not the chromaticity is outside the standard color gamut, but it is possible to grasp whether or not the chromaticity is close to the standard color gamut. difficult. When the chromaticity is outside the standard color gamut, it is difficult to grasp the degree of deviation from the standard color gamut, and the degree of color change when the color gamut of the image is compressed to the standard color gamut. It's hard.

Therefore, an object of the present invention is to provide a technique that makes it possible to easily grasp the relative position of chromaticity with respect to the color gamut.

A first aspect of the present invention is a setting means for setting a color gamut, a conversion means for converting a pixel value into a chromaticity, and the chromaticity with respect to the color gamut based on the color gamut and the chromaticity. It has an acquisition means for acquiring information about a relative position and a control means for controlling to display the chromaticity, and the control means changes the display indicating the chromaticity according to the information. It is a display control device characterized by the above.

A second aspect of the present invention is a first setting means for setting a first color gamut, a second setting means for setting a second color gamut, the first color gamut, and the second color gamut. Based on the above, the coloring means for coloring the image in the first color gamut and the control means for controlling the display of the image after coloring are provided, and the coloring means has the second color. It is a display control device characterized in that the coloring is changed according to the relative position of the chromaticity before coloring with respect to a gamut.

A third aspect of the present invention is a step of setting a color gamut, a step of converting a pixel value into a chromaticity, and a relative position of the chromaticity with respect to the color gamut based on the color gamut and the chromaticity. A display control having a step of acquiring information regarding the color gamut and a step of controlling the display to indicate the color gamut, and the display indicating the color gamut is changed according to the information. The method.

A fourth aspect of the present invention is based on a step of setting a first color gamut, a step of setting a second color gamut, and the first color gamut and the second color gamut. It has a step of coloring an image in a first color gamut and a step of controlling to display the colored image.
It is a display control method characterized in that the coloring is changed according to the relative position of the chromaticity before coloring with respect to the second color gamut.

A fifth aspect of the present invention is a program for making a computer function as each means of the above-mentioned display control device.

According to the present invention, the relative position of the chromaticity with respect to the color gamut can be easily grasped.

It is a block diagram which shows the structural example of the display device which concerns on Example 1. FIG. It is a flowchart which shows an example of the chromaticity display processing which concerns on Example 1. FIG. It is a figure for demonstrating the determination example of whether or not the chromaticity is within a reference color range. It is a figure for demonstrating the calculation example of various ratios with respect to the relative position of chromaticity. It is a figure which shows the display example of the numerical value of the calculated ratio. It is a block diagram which shows the structural example of the display device which concerns on Examples 2 and 3. It is a flowchart which shows an example of the coloring display processing which concerns on Example 2.3. It is a figure which shows an example of the relationship between the chromaticity before coloring and the chromaticity after coloring. It is a figure which shows an example of the relationship between the chromaticity before coloring and the chromaticity after coloring. It is a figure which shows the display example of the chromaticity display function. It is a figure which shows the display example of the color-outside coloring display function.

<Example 1>
Hereinafter, Example 1 of the present invention will be described. The display control device according to the first embodiment displays the chromaticity plotted on the chromaticity diagram as a function for confirming the chromaticity of the image (image) (a function of displaying the chromaticity of the image). It has a chromaticity display function. Then, the display control device acquires information on the relative position of the chromaticity of the image with respect to the set color gamut (information on the positional relationship between the color gamut and the chromaticity), and displays the chromaticity display function according to the information. change. This makes it possible to easily grasp the relative position of the chromaticity with respect to the color gamut, and by extension, the degree to which the color gamut is widely used, the degree to which the chromaticity deviates from the standard color gamut, and the image color gamut ( It becomes possible to easily grasp the degree of color change when compressing the color gamut of an image to the reference color gamut. In the following, an example in which the display device has the above-mentioned function of the display control device (device capable of controlling the display on the display device) will be described, but the display control device is a device (personal computer or the like) separate from the display device. There may be.

FIG. 1 is a block diagram showing a configuration example of the display device 100 according to the first embodiment. The display device 100 includes a video signal input unit 101, a pixel designation unit 102, a video signal analysis unit 103, a video color gamut setting unit 104, a chromaticity conversion unit 105, a reference color gamut setting unit 106, a ratio calculation unit 107, and a display control unit. It has 108 and a display unit 109.

The video signal input unit 101 receives the video signal from the outside and outputs it to the video signal analysis unit 103. The video signal is a video signal in any color gamut such as the 2020 color gamut or the 709 color gamut. The 2020 color gamut is ITU-R BT. It is a color gamut defined by 2020, and the 709 color gamut is defined by ITU-R BT. It is a color gamut defined by 709. The video signal input unit 101 is, for example, an input terminal compliant with a SDI (Serial Digital Interface) standard. The video signal input unit 101 may be an input terminal compliant with a standard such as HDMI (High-Definition Multimedia Interface). The display device 100 may have a storage unit for storing the video signal, and the video signal input unit 101 may acquire the video signal recorded in the storage unit of the display device 100.

The pixel designation unit 102 outputs the position of the pixel designated by the user to the video signal analysis unit 103. The position of the pixel is, for example, a coordinate with the upper left corner of the image as the origin (coordinates (horizontal position, vertical position) = (0,0)). When the pixel position is not specified by the user, the pixel designation unit 102 outputs a predetermined initial value (for example, coordinates (0,0)) to the video signal analysis unit 103 as the pixel position. The display device 100 can receive various user operations (operations for specifying pixel positions, power on / off operations, etc.) via operation units (not shown) such as buttons, keys, and a touch panel, for example. ..

The video signal analysis unit 103 analyzes the video signal output from the video signal input unit 101, acquires the pixel value at the position designated (output) by the pixel designation unit 102 from the video signal, and acquires the pixel value. Is output to the chromaticity conversion unit 105. The pixel value is, for example, an RGB value.

The video color gamut setting unit 104 outputs (sets) the video color gamut designated by the user to the chromaticity conversion unit 105, the ratio calculation unit 107, and the display control unit 108. The image color gamut is, for example, a 709 color gamut or a 2020 color gamut.

The chromaticity conversion unit 105 converts the pixel value output from the video signal analysis unit 103 into a chromaticity (xy value) based on the video color gamut output from the video color gamut setting unit 104. Then, the chromaticity conversion unit 105 outputs the obtained chromaticity to the ratio calculation unit 107 and the display control unit 108. For example, the chromaticity conversion unit 105 converts an RGB value into an XYZ value and a XYZ value into an xy value.

When the video color gamut is 709 color gamut, RGB values (R value, G value, B value) = (R, G, B) and XYZ values (X value, Y value, Z value) = (X, Y) , Z) is as follows.
X = 0.412 x R + 0.358 x G + 0.181 x B
Y = 0.213 x R + 0.715 x G + 0.072 x B
Z = 0.019 x R + 0.119 x G + 0.951 x B

When the video color gamut is the 2020 color gamut, the relationship between the RGB values (R, G, B) and the XYZ values (X, Y, Z) is as follows.
X = 0.637 × R + 0.145 × G + 0.169 × B
Y = 0.263 × R +0.678 × G +0.059 × B
Z = 0.000 x R + 0.028 x G + 1.060 x B

The conversion formula from the XYZ value (X, Y, Z) to the xy value (x value, y value) = (x, y) is as follows.
x = X / (X + Y + Z)
y = Y / (X + Y + Z)

The reference color gamut setting unit 106 outputs (sets) the reference color gamut designated by the user to the ratio calculation unit 107 and the display control unit 108. The reference color gamut is, for example, 709 color gamut. If the standard color gamut is not specified by the user, the standard color gamut setting unit 106 outputs "no standard color gamut".

The ratio calculation unit 107 is based on the chromaticity output from the chromaticity conversion unit 105, the image color gamut output from the image color gamut setting unit 104, and the reference color gamut output from the reference color gamut setting unit 106. Acquires information about the relative position of chromaticity with respect to the image color gamut or the reference color gamut. The information regarding the relative position is not particularly limited, but in the first embodiment, the ratio calculation unit 107 calculates the ratio regarding the relative position as the information regarding the relative position, and outputs the calculated ratio to the display control unit 108. When the reference color gamut is not set, the ratio calculation unit 107 calculates and outputs the ratio in the video color gamut based on the video color gamut and the chromaticity. When the reference color gamut is set, the ratio calculation unit 107 calculates and outputs a ratio based on at least the reference color gamut and the chromaticity. Specifically, when the standard color gamut is set and the chromaticity is within the standard color gamut, the ratio calculation unit 107 calculates and outputs the ratio in the standard color gamut based on the standard color gamut and the chromaticity. .. When the reference color gamut is set and the chromaticity is outside the reference color gamut, the ratio calculation unit 107 calculates and outputs the image color gamut, the reference color gamut, and the out-of-reference color gamut ratio based on the chromaticity. The details of the ratio within the image color range, the ratio within the standard color range, and the ratio outside the standard color range will be described later.

The display control unit 108 controls the display unit 109 so as to plot the chromaticity output from the chromaticity conversion unit 105 on the xy chromaticity diagram (chromaticity display function). Further, in the chromaticity display function, the display control unit 108 displays the image color gamut output from the image color gamut setting unit 104 and the reference color gamut output from the reference color gamut setting unit 106 on the xy chromaticity diagram. Control as shown. Then, the display control unit 108 colors according to the information acquired by the ratio calculation unit 107, that is, the ratio output from the ratio calculation unit 107 (the ratio in the image color range, the ratio in the reference color range, or the ratio outside the reference color range). Change the display of the degree display function. The display unit 109 has, for example, a liquid crystal panel and a backlight. The display unit 109 may be configured by an OLED (Organic Light Emitting Diode) panel or the like.

FIG. 2 is a flowchart showing an example of chromaticity display processing of the display device 100. The chromaticity display process of FIG. 2 is executed for each frame of the video. Here, it is assumed that the position (pixel position) is specified by the pixel designation unit 102 and the image color gamut is set by the image color gamut setting unit 104 in advance.

In step S201, the video signal input unit 101 receives the video signal (1 frame).

In step S202, the video signal analysis unit 103 acquires a pixel value at a position previously designated by the pixel designation unit 102 from the video signal received in step S201.

In step S203, the chromaticity conversion unit 105 converts the pixel value acquired in step S202 into chromaticity based on the image color gamut preset by the image color gamut setting unit 104.

In step S204, the ratio calculation unit 107 determines whether or not the reference color gamut has been set in advance by the reference color gamut setting unit 106, that is, whether or not the reference color gamut has been set. If the reference color gamut is set, the process proceeds to step S205, and if the reference color gamut is not set, the process proceeds to step S209.

In step S205, the ratio calculation unit 107 determines whether or not the chromaticity obtained in step S203 is within the reference color gamut set by the reference color gamut setting unit 106. If the chromaticity is within the reference color range, the process proceeds to step S206, and if the chromaticity is outside the reference color range, the process proceeds to step S208.

Here, an example of determining whether or not the chromaticity is within the reference color range will be described with reference to FIGS. 3 (A) and 3 (B). FIGS. 3 (A) and 3 (B) show an example of an xy chromaticity diagram. On the xy chromaticity diagram of FIGS. 3 (A) and 3 (B), the image color gamut 301, the reference color gamut 302, and the chromaticity (chromaticity 303a in FIG. 3 (A) and chromaticity in FIG. 3 (B)). 303b)) and the white point 304 are shown. FIG. 3A shows an example in which it is determined that the chromaticity 303a is within the reference color gamut 302. FIG. 3B shows an example in which it is determined that the chromaticity 303b is outside the reference color gamut 302.

In FIGS. 3A and 3B, the video color gamut 301 is the 2020 color gamut, and the reference color gamut 302 is the 709 color gamut. In both the video color gamut 301 and the reference color gamut 302, the xy value corresponding to the maximum R value (G value and B value are zero), the xy value corresponding to the maximum G value (R value and B value are zero), and , A gamut of triangles connecting xy values corresponding to the maximum B value (R and G values are zero). Specifically, in the video color gamut 301 (2020 color gamut), the xy value (x value, y value) = (0.708, 0.292), the xy value (0.170, 0.797), and. It is a gamut of triangles connecting xy values (0.131, 0.046). The reference color gamut 302 (709 color gamut) connects the xy value (0.640, 0.331), the xy value (0.300, 0.600), and the xy value (0.150, 0.060). It is a gamut of a triangle. The white point 304 is a chromaticity representing white color at a predetermined color temperature. In FIGS. 3A and 3B, the white point 304 is a white point at the color temperature D65 in the 2020 color gamut, and is an xy value (0.313, 0.329).

In FIG. 3A, the chromaticity 303a is an xy value (0.4, 0.3). In this case, there is a chromaticity 303a in the reference color gamut 302, and it is determined as such. In FIG. 3B, the chromaticity 303b is an xy value (0.2, 0.6). In this case, the chromaticity 303b is outside the reference color gamut 302, and the determination is made as such.

Returning to the description of FIG. In step S206, the ratio calculation unit 107 calculates the ratio in the reference color gamut based on the chromaticity obtained in step S203 and the reference color gamut set by the reference color gamut setting unit 106. The range of the ratio within the reference color range is, for example, a range of 0 to 100%.

In step S207, the display control unit 108 determines the display color of the chromaticity (chromaticity points plotted on the xy chromaticity diagram) obtained in step S203 according to the ratio within the reference color range calculated in step S206. do. For example, when white is displayed as an RGB value (1023, 1023, 1023), the RGB value (R, G, B) of the chromaticity point is calculated from the reference color range ratio Rirg as follows. In this case, the chromaticity point is achromatic.
R = G = B = 1023 × Rirg

In step S208, the ratio calculation unit 107 sets the chromaticity obtained in step S203, the image color gamut set by the image color gamut setting unit 104, and the reference color gamut set by the reference color gamut setting unit 106. Based on this, the out-of-standard color gamut ratio is calculated. The range of the out-of-reference color ratio is, for example, a range of 0 to 100%.

In step S209, the display control unit 108 determines the display color of the chromaticity (chromaticity points plotted on the xy chromaticity diagram) obtained in step S203 according to the out-of-reference color range ratio calculated in step S208. do. For example, as shown below, the brightness V of the designated pixel in the HSV color space (pixel designated by the user; pixel obtained in chromaticity in step S203; pixel at the position designated by the pixel designation unit 102) and the reference color. The brightness Vd of the chromaticity point is calculated from the out-of-region ratio Rorg. The hue and saturation of the chromaticity point are the same as the hue and saturation of the designated pixel. In this case, the chromaticity point is chromatic.
Vd = V × Rorg

In step S210, the ratio calculation unit 107 calculates the ratio in the video color gamut based on the chromaticity obtained in step S203 and the video color gamut set by the video color gamut setting unit 104. The range of the ratio in the image color range is, for example, the range of 0 to 100%.

In step S211 the display control unit 108 determines the display color of the chromaticity (chromaticity points plotted on the xy chromaticity diagram) obtained in step S203 according to the ratio in the image color range calculated in step S210. do. For example, as shown below, the brightness V of the designated pixel in the HSV color space (pixel designated by the user; pixel obtained in chromaticity in step S203; pixel at the position designated by the pixel designation unit 102) and the image color. The brightness Vd of the chromaticity point is calculated from the intra-regional ratio Ri. The hue and saturation of the chromaticity point are the same as the hue and saturation of the designated pixel. In this case, the chromaticity point is chromatic.
Vd = V × Ri

Here, an example of calculating the ratio in the reference color range, the ratio outside the reference color range, and the ratio in the video color range will be described with reference to FIGS. 4 (A) to 4 (C). 4 (A) to 4 (C) show an example of an xy chromaticity diagram. 4 (A) to 4 (C) show the color gamut (image color gamut 301 and reference color gamut 302 in FIGS. 4 (A) and 4 (B), image color gamut 301 in FIG. 4 (C)), and colors. Degrees (color gamut 303a in FIG. 4A, color gamut 303b in FIGS. 4B and 4C), and white spots 304 are shown. The image color gamut 301, the reference color gamut 302, the chromaticities 303a and 303b, and the white point 304 are the same as those in FIGS. 3A and 3B. Further, FIGS. 4A to 4C show a straight line passing through the white point 304 and the chromaticity, and the intersection of the straight line and the edge of the color gamut. FIG. 4A is a diagram for explaining a calculation example of the ratio within the reference color range, FIG. 4B is a diagram for explaining a calculation example of the ratio outside the reference color range, and FIG. 4C is an image. It is a figure explaining the calculation example of the ratio in a color region.

In FIG. 4A, since the reference color gamut 302 is set and the chromaticity 303a is in the reference color gamut 302, the ratio in the reference color gamut is calculated. The straight line 401a is a straight line passing through the white point 304 and the chromaticity 303a. The intersection point 402a is an intersection point between the straight line 401a and the edge of the reference color gamut 302. The ratio within the reference color gamut is the ratio of the distance from the white point 304 to the intersection 402a (the edge of the reference color gamut 302) and the distance from the white point 304 to the chromaticity 303a. For example, the ratio within the reference color range is the ratio of the distance from the white point 304 to the chromaticity 303a with respect to the distance from the white point 304 to the intersection 402a. In FIG. 4A, the intersection 402a is an xy value (0.515, 0.262). Therefore, the distance from the white point 304 to the intersection 402a is 0.313, the distance from the white point 304 to the chromaticity 303a is 0.092, and the ratio within the reference color range is 29.392%.

In FIG. 4B, since the reference color gamut 302 is set and the chromaticity 303b is outside the reference color gamut 302, the out-of-reference color gamut ratio is calculated. The straight line 401b is a straight line passing through the white point 304 and the chromaticity 303b. The intersection point 402b is an intersection point between the straight line 401b and the edge of the reference color gamut 302. The intersection 403b is an intersection between the straight line 401b and the edge of the image color gamut 301. The out-of-reference color gamut ratio is the ratio of the distance from the intersection 402b (edge of the reference color gamut 302) to the intersection 403b (edge of the image color gamut 301) and the distance from the intersection 402b to the chromaticity 303b. For example, the out-of-reference color ratio is the ratio of the distance from the intersection 402b to the chromaticity 303b with respect to the distance from the intersection 402b to the intersection 403b. In FIG. 4B, the intersection 402b is an xy value (0.260, 0.456) and the intersection 403b is an xy (0.165, 0.685). Therefore, the distance from the intersection 402b to the intersection 403b is 0.249, the distance from the intersection 402b to the chromaticity 303b is 0.157, and the out-of-reference color range ratio is 62.962%.

The information on the relative position of the chromaticity with respect to the standard color gamut is not limited to the ratio within the standard color gamut and the ratio outside the standard color gamut. For example, regarding the chromaticity in the standard color gamut, the information on the relative position of the chromaticity with respect to the standard color gamut is the inverse of the ratio in the standard color gamut, the distance from the white point to the chromaticity, and the edge of the standard color gamut to the chromaticity. It may be a distance or the like. Regarding the chromaticity outside the standard color gamut, the information on the relative position of the chromaticity with respect to the standard color gamut is the inverse of the ratio outside the standard color gamut, the distance from the edge of the standard color gamut to the chromaticity, and the edge of the image color gamut to the chromaticity. It may be the distance of.

In FIG. 4C, since the reference color gamut 302 is not set, the ratio within the video color gamut is calculated. The straight line 401c is a straight line passing through the white point 304 and the chromaticity 303b. The intersection point 402c is an intersection point between the straight line 401c and the edge of the image color gamut 301. The ratio in the image color gamut is the ratio of the distance from the white point 304 to the intersection 402c (the edge of the image color gamut 301) and the distance from the white point 304 to the chromaticity 303b. For example, the ratio in the image color region is the ratio of the distance from the white point 304 to the chromaticity 303b with respect to the distance from the white point 304 to the intersection 402c. In FIG. 4C, the intersection 402c is an xy value (0.165, 0.685). Therefore, the distance from the white point 304 to the intersection 402c is 0.386, the distance from the white point 304 to the chromaticity 303b is 0.294, and the ratio in the image color range is 76.125%.

The information on the relative position of the chromaticity with respect to the video color gamut is not limited to the ratio within the video color gamut. For example, the information on the relative position of the chromaticity with respect to the video color gamut may be the inverse of the ratio in the video color gamut, the distance from the white point to the chromaticity, the distance from the edge of the video color gamut to the chromaticity, and the like.

Returning to the description of FIG. In step S212, the display control unit 108 displays the xy chromaticity diagram showing the chromaticity obtained in step S203 and the video color gamut set by the video color gamut setting unit 104 on the display unit 109. When the reference color gamut is set by the reference color gamut setting unit 106, the display control unit 108 displays the xy chromaticity diagram showing the chromaticity, the image color gamut, and the reference color gamut on the display unit 109. The display control unit 108 plots the chromaticity on the xy chromaticity diagram so that the chromaticity (chromaticity point) is displayed in the display color determined in step S207, step S209, or step S211.

As described above, according to the first embodiment, when the reference color gamut is not set, information on the relative position of the chromaticity with respect to the video color gamut (ratio within the video color gamut) is acquired, and according to the information. The display of the chromaticity display function (display color of the chromaticity point) is changed. As a result, the relative position of the chromaticity with respect to the video color gamut can be easily grasped, and by extension, the degree to which the video color gamut can be widely used can be easily grasped. For example, as described with reference to FIG. 2, the larger the ratio in the video color gamut, the higher the brightness of the chromaticity point, and the wider the color gamut used in the video color gamut, the brighter the chromaticity point is displayed. Therefore, it is easy to grasp whether the image color gamut is widely used.

In addition, when the standard color gamut is set, information on the relative position of the chromaticity with respect to the standard color gamut (ratio within the standard color gamut or ratio outside the standard color gamut) is acquired, and the chromaticity display function is used according to the information. The display (display color of the chromaticity point) is changed. This makes it possible to easily grasp the relative position of the chromaticity with respect to the standard color gamut, and by extension, the degree to which the standard color gamut is widely used, the degree to which the chromaticity deviates from the standard color gamut, and the image color. It becomes possible to easily grasp the degree of color change when the gamut is compressed to the reference color gamut. For example, as described with reference to FIG. 2, if an achromatic color that is closer to white as the ratio in the reference color range is larger is used as the display color of the chromaticity point, the wider the color range that can be used in the reference color range, the closer to white. Since the chromaticity points are displayed in color, it is easy to understand whether the standard color range is widely used. In addition, if the brightness of the chromaticity points is increased as the out-of-reference color gamut ratio is increased, the chromaticity points are displayed in brighter colors as the chromaticity points are farther from the reference color gamut, so that the chromaticity deviates from the reference color gamut. You can easily grasp the degree of doing. Furthermore, by changing the display color of the chromaticity point, the chromaticity becomes the standard color, such as an achromatic color when the chromaticity is within the standard color range and a chromatic color when the chromaticity is outside the standard color range. It is very easy to know whether or not it is in the area.

Although an example of plotting the chromaticity of a pixel specified by the user on a chromaticity diagram has been described, the present invention is not limited to this. For example, a plurality of chromaticities corresponding to a plurality of pixels included in a part of an image such as an area specified by a user or an area having a predetermined feature (for example, an area in which a predetermined object exists). , May be plotted on the chromaticity diagram. The chromaticity of all pixels of the image may be plotted on the chromaticity diagram.

Further, an example of changing the display color of the chromaticity point has been described, but the present invention is not limited to this. For example, the numerical value of the calculated ratio (the ratio in the image color range, the ratio in the reference color range, or the ratio outside the reference color range) may be displayed on the display unit 109. This also makes it possible to easily grasp the relative position of the chromaticity with respect to the color gamut, and by extension, the degree to which the color gamut is widely used, the degree to which the chromaticity deviates from the standard color gamut, and the image color gamut. It becomes possible to easily grasp the degree of color change when compressing to the standard color gamut.

5 (A) and 5 (B) show a display example of the numerical value of the calculated ratio (the ratio in the image color range, the ratio in the standard color range, or the ratio outside the standard color range). 5 (A) and 5 (B) show an example of an xy chromaticity diagram. Similar to FIGS. 3 (A) and 3 (B), the image color gamut 301, the reference color gamut 302, and the white point 304 are shown on the xy chromaticity diagram of FIGS. 5 (A) and 5 (B). Has been done. The chromaticity 500a is plotted on the xy chromaticity diagram of FIG. 5A. The ratio within the reference color range calculated using the chromaticity 500a is 20%, and the character string of "20%" is shown in association with the chromaticity 500a. The chromaticity 500b is plotted on the xy chromaticity diagram of FIG. 5 (B). The ratio within the reference color range calculated using the chromaticity 500b is 20%, and the character string of "90%" is shown in association with the chromaticity 500b. Similarly, when the ratio within the video color range or the ratio outside the standard color range is calculated, the numerical value is shown.

<Example 2>
Hereinafter, Example 2 of the present invention will be described. In the following, points different from Example 1 (configuration, processing, etc.) will be described in detail, and description of the same points as in Example 1 will be omitted as appropriate.

The display control device according to the second embodiment has a function for confirming the chromaticity of the image (image) (a function of displaying the chromaticity of the image), and colors the image when displaying the image. It has a coloring display function to be performed. Then, when coloring the pixels of the image, the display control device changes the coloring according to the relative position of the chromaticity before coloring (chromaticity based on the image color gamut) with respect to the reference color gamut. This makes it possible to easily grasp the relative position of the color gamut before coloring with respect to the standard color gamut, and by extension, the degree to which the color gamut before coloring deviates from the standard color gamut, and the image color gamut as the standard color gamut. The degree of color change during compression can be easily grasped. In the following, an example in which the display device has the above-mentioned function of the display control device (device capable of controlling the display on the display device) will be described, but the display control device is a device (personal computer or the like) separate from the display device. There may be.

FIG. 6 is a block diagram showing a configuration example of the display device 600 according to the second embodiment. The display device 600 includes a video signal input unit 101, a video color gamut setting unit 104, a video generation unit 601, a reference color gamut setting unit 106, a coloring unit 602, a display control unit 603, and a display unit 109. The video signal input unit 101, the video color gamut setting unit 104, the reference color gamut setting unit 106, and the display unit 109 are the same as those in the first embodiment.

The video generation unit 601 is based on the video color gamut output from the video color gamut setting unit 104, and has each pixel value of the video signal output from the video signal input unit 101 so that the video signal in the color gamut can be obtained. To convert. Then, the image generation unit 601 outputs the obtained image signal to the coloring unit 602. The conversion method of the pixel value is not particularly limited. For example, the pixel value may be converted by an operation using a mathematical formula, or the pixel value may be converted by using a LUT (Look Up Table). A conversion matrix or LUT to be applied to the pixel values is generated in advance based on the RGB chromaticity of the video color gamut (chromaticity of the vertices of the triangle) and the panel color gamut (maximum color gamut that can be displayed).

The coloring unit 602 colors the video signal output from the video generation unit 601 based on the video color gamut output from the video color gamut setting unit 104 and the reference color gamut output from the reference color gamut setting unit 106. To give. At that time, the coloring unit 602 changes the coloring for each pixel according to the relative position of the chromaticity before coloring (chromaticity based on the image color gamut) with respect to the reference color gamut. Then, the coloring unit 602 outputs the video signal after the coloring process to the display control unit 603. The coloring process is performed using, for example, a 3DLUT (three-dimensional Look Up Table) in which RGB values (three values of R value, G value, and B value) are used as input / output values. The display device 600 may be able to accept an on / off operation of the coloring process via an operation unit (not shown). When the reference color gamut is not set or the coloring process is set to off, a through LUT (LUT that uses the input value as the output value as it is) is used for the coloring process.

The display control unit 603 controls the display unit 109 so as to display an image (image after coloring) corresponding to the image signal output from the coloring unit 602.

FIG. 7 is a flowchart showing an example of the coloring display processing of the display device 600. The coloring display process of FIG. 7 is executed for each frame of the video. Here, it is assumed that the image color gamut is set in advance by the image color gamut setting unit 104.

In step S701, the video signal input unit 101 receives the video signal (1 frame).

In step S702, the video generation unit 601 converts the video signal received in step S701 based on the video color gamut preset by the video color gamut setting unit 104 (generation of video in the video color gamut).

In step S703, the coloring unit 602 determines whether or not the reference color gamut has been set in advance by the reference color gamut setting unit 106, that is, whether or not the reference color gamut has been set. If the reference color gamut is set, the process proceeds to step S704, and if the reference color gamut is not set, the process proceeds to step S705.

In step S704, the coloring unit 602 has a video color gamut preset by the video color gamut setting unit 104 and a reference color gamut preset by the reference color gamut setting unit 106 as LUTs used for the coloring process. LUT is determined according to.

FIG. 8 is a diagram showing an example of the relationship between the chromaticity before coloring and the chromaticity after coloring (0% to 100%). According to the relationship of FIG. 8, the saturation of the region where the chromaticity is within the reference color range in the image before coloring is converted to 0%. That is, in the image before coloring, the color in the region where the chromaticity is within the reference color range is converted into a monochrome color. Further, in the image before coloring, the color in the region where the chromaticity is outside the reference color gamut is converted into a color having higher saturation as the chromaticity is farther from the reference color gamut. The hue and lightness after coloring are not particularly limited, but for example, as the hue after coloring (0 to 360%), a predetermined hue, for example, red, regardless of whether the hue before coloring is within the reference color range. Hue (0%) is adopted. The lightness after coloring (0 to 100%) is the lightness before coloring when the chromaticity before coloring is within the standard color range, and the predetermined lightness when the chromaticity before coloring is outside the standard color range (for example). 100%) is adopted. In step S704, a LUT that realizes such coloring (color conversion) is determined.

Returning to the description of FIG. In step S705, the coloring unit 602 determines the through LUT as the LUT used for the coloring process.

In step S706, the coloring unit 602 applies the LUT determined in step S704 or step S705 to the video signal generated in step S702 (coloring process).

In step S707, the display control unit 603 displays an image (image after coloring) corresponding to the image signal after the coloring process of step S706 on the display unit 109.

As described above, according to the second embodiment, when coloring the pixels of the image, the coloring is changed according to the relative position of the chromaticity before coloring (chromaticity based on the image color gamut) with respect to the reference color gamut. Will be done. This makes it possible to easily grasp the relative position of the color gamut before coloring with respect to the standard color gamut, and by extension, the degree to which the color gamut before coloring deviates from the standard color gamut, and the image color gamut as the standard color gamut. The degree of color change during compression can be easily grasped. For example, as described with reference to FIG. 8, in the image before coloring, the color in the region where the chromaticity is outside the reference color gamut is converted into a color having higher saturation as the chromaticity is farther from the reference color gamut. To. As a result, the farther the chromaticity before coloring is from the reference color gamut, the more vivid the color is, so it is possible to easily grasp whether the chromaticity before coloring deviates from the reference color gamut. Further, in the image before coloring, the color in the region where the chromaticity is within the reference color range is converted into a monochrome color. This makes it possible to easily grasp whether or not the chromaticity before coloring is within the reference color range.

<Example 3>
Hereinafter, Example 3 of the present invention will be described. In the following, points different from Example 2 (configuration, processing, etc.) will be described in detail, and description of the same points as in Example 2 will be omitted as appropriate. The configuration of the display device and the coloring display processing according to the third embodiment are the same as those of the second embodiment (FIGS. 6 and 7). However, the LUT determined in step S704 is different from that of the second embodiment.

FIG. 9 is a diagram showing an example of the relationship between the chromaticity before coloring and the chromaticity after coloring (0% to 100%). According to the relationship of FIG. 9, in the image before coloring, the color of the region where the chromaticity is within the reference color range has a higher saturation as the color is farther from the white point and a lower saturation than the saturation before coloring. Converted to color. Further, in the image before coloring, the color in the region where the chromaticity is outside the reference color range is converted into a color having a higher saturation as the color saturation is farther from the reference color range and higher than the saturation before coloring. .. The hue and lightness after coloring are not particularly limited. For example, the hue and lightness after coloring are not particularly limited. For example, the hue before coloring is adopted as the hue after coloring, and the hue before coloring is adopted as the lightness after coloring. Is adopted. That is, the hue and lightness do not change before and after the application of the LUT. In step S704 of the third embodiment, the LUT that realizes such coloring (color conversion) is determined.

As described above, also in Example 3, when coloring the pixels of the image, the coloring is changed according to the relative position of the chromaticity before coloring (chromaticity based on the image color gamut) with respect to the reference color gamut. .. As a result, the same effect as in Example 2 can be obtained. For example, as described with reference to FIG. 9, in the image before coloring, the color in the region where the chromaticity is within the reference color range is converted into a color having a saturation lower than the saturation before coloring, and the chromaticity is changed. The color of the region where is within the reference color range is converted into a color having a higher saturation than the saturation before coloring. As a result, after coloring, the region where the chromaticity before coloring is outside the reference color range is displayed with more emphasis than the region where the chromaticity before coloring is within the reference color range. As a result, it is possible to easily grasp whether or not the chromaticity before coloring is within the reference color range. The region where the chromaticity before coloring is within the standard color range is displayed with higher saturation as the chromaticity before coloring is farther from the white point, and the region where the chromaticity before coloring is outside the standard color range is before coloring. The farther the color saturation is from the standard color range, the higher the saturation is displayed. As a result, the degree to which the standard color gamut can be widely used, the degree to which the chromaticity before coloring deviates from the standard color gamut, the degree of color change when the image color gamut is compressed to the standard color gamut, etc. It becomes easy to grasp. Further, in Example 3, since the hue and lightness before coloring are maintained, the above effect can be obtained while displaying the image similar to the image before coloring.

The above-mentioned examples (including modifications) are merely examples, and the present invention also includes configurations obtained by appropriately modifying or changing the above-mentioned configurations within the scope of the gist of the present invention. .. The present invention also includes a configuration obtained by appropriately combining the above-mentioned configurations. For example, in Example 2 and Example 3, the color is changed by changing the saturation, but the color may be changed by changing the lightness and the hue. For example, in the second embodiment, the color in the region of the image before coloring whose chromaticity is within the reference color range is converted into a monochrome color, but it is not necessary to convert the color. When not converting, the color in the region where the chromaticity is outside the reference color gamut in the image before coloring may be converted into a monochrome color, and the brightness may be set as the chromaticity is farther from the reference color gamut.

<Other Examples>
The present invention supplies a program that realizes one or more functions of the above-described embodiment to a system or device via a network or storage medium, and one or more processors in the computer of the system or device reads and executes the program. It can also be realized by the processing to be performed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

100, 600: Display device 104: Video color gamut setting unit 105: Chromaticity conversion unit 107: Ratio calculation unit 108, 603: Display control unit

Claims (16)

The first setting means for setting the first color gamut and
A conversion means that converts pixel values to chromaticity,
An acquisition means for acquiring the first information regarding the relative position of the chromaticity with respect to the first color gamut based on the first color gamut and the chromaticity.
It has a control means for controlling to display the chromaticity.
The control means is a display control device, characterized in that the display indicating the chromaticity is changed according to the first information. As the first information, the acquisition means acquires the ratio of the distance from the white point to the edge of the first color gamut and the distance from the white point to the chromaticity on the chromaticity diagram. The display control device according to claim 1, wherein the display control device is characterized in that. Further having a second setting means for setting a second color gamut,
When the second color gamut is set,
The acquisition means acquires the second information regarding the relative position of the chromaticity with respect to the second color gamut based on the second color gamut and the chromaticity.
The display control device according to claim 1 or 2, wherein the control means changes the display according to the second information. When the second color gamut is set and the chromaticity is within the second color gamut, the acquisition means is based on the second color gamut and the chromaticity. The display control device according to claim 3, wherein the second information is acquired. When the second color gamut is set and the chromaticity is within the second color gamut, the acquisition means obtains the white point on the chromaticity diagram as the second information. The display control device according to claim 4, wherein the ratio between the distance from the second color gamut to the edge of the second color gamut and the distance from the white point to the chromaticity is acquired. When the second color gamut is set and the chromaticity is outside the second color gamut, the acquisition means obtains the first color gamut, the second color gamut, and the color. The display control device according to any one of claims 3 to 5, wherein the second information is acquired based on the degree. When the second color gamut is set and the chromaticity is outside the second color gamut, the acquisition means uses the second information as the second information on the chromaticity diagram. 6. The sixth aspect of the present invention is to obtain the ratio of the distance from the edge of the second color gamut to the edge of the first color gamut and the distance from the edge of the second color gamut to the chromaticity. The display control device described in. The display control device according to any one of claims 1 to 7, wherein the display indicating the chromaticity is a display in which the chromaticity is plotted on a chromaticity diagram. The first setting means for setting the first color gamut and
A second setting means for setting the second color gamut, and
A coloring means for coloring an image in the first color gamut based on the first color gamut and the second color gamut.
It has a control means for controlling the display of the colored image.
The coloring means is a display control device, characterized in that the coloring is changed according to the relative position of the chromaticity before coloring with respect to the second color gamut. The coloring means converts a color in a region of the image before coloring whose chromaticity is outside the second color gamut into a color having a higher saturation as the chromaticity is farther from the second color gamut. The display control device according to claim 9. The coloring means obtains a color in a region of the image before coloring whose chromaticity is outside the second color gamut, a saturation higher as the chromaticity is farther from the second color gamut, and a predetermined hue. The display control device according to claim 10, further comprising converting to a color having a predetermined brightness. The coloring means is
In the image before coloring, the color in the region where the chromaticity is within the second color range is converted into a color having a chromaticity higher as the chromaticity is farther from the white point and lower than the chromaticity before coloring. death,
In the image before coloring, the color in the region where the chromaticity is outside the second color range is higher as the chromaticity is farther from the second color range, and the saturation is higher than the saturation before coloring. The display control device according to claim 9, wherein the color is converted into the color of. The coloring means is
In the image before coloring, the color of the region where the chromaticity is within the second color range is higher as the chromaticity is farther from the white point and lower than the saturation before coloring, the saturation before coloring. To the hue and the color of the lightness before coloring,
In the image before coloring, the color in the region where the chromaticity is outside the second color range is higher as the chromaticity is farther from the second color range, and the saturation is higher than the saturation before coloring. The display control device according to claim 12, wherein the color is converted into a color before coloring and a color with lightness before coloring. Steps to set the color gamut and
Steps to convert pixel values to chromaticity,
A step of acquiring information about the relative position of the chromaticity with respect to the color gamut based on the color gamut and the chromaticity.
It has a step of controlling to display the chromaticity.
A display control method characterized in that the display indicating the chromaticity is changed according to the information. The step to set the first color gamut and
The step to set the second color gamut and
A step of coloring an image in the first color gamut based on the first color gamut and the second color gamut, and
It has a step of controlling to display the image after coloring, and has a step.
A display control method characterized in that the coloring is changed according to the relative position of the chromaticity before coloring with respect to the second color gamut. A program for making a computer function as each means of the display control device according to any one of claims 1 to 12.

Images