JP2010183232A - Color gamut conversion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems, wherein a look-up table is required to make a device scale become large, because display device color gamut boundary information is necessary after conversion to a space, such as, L*a*b* in the conventional color gamut extension, and it is difficult to make corrections and adjustments so as to make the colors natural and it is difficult compatible with different devices in color gamut expansion. <P>SOLUTION: A color gamut conversion device for converting color data of a first color gamut into color data of a second color gamut includes a color gamut converting part for controlling the color gamut conversion characteristics of color data of the first color gamut by a correction signal, and a compositing section for compositing the color data of the first color gamut with color data converted by the color gamut converting part, to output color data of a second color gamut, and can eliminate a look-up table and make the scale small. In addition, in color gamut expansion, it is possible to make such corrections and adjustments which would make colors natural, and the color gamut conversion device to be able to compatible with different devices. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a color gamut conversion device and a color gamut conversion which are easy to adjust while performing color gamut expansion for natural color display when color data is displayed on a device having a color gamut wider than the input color gamut. The present invention relates to a method, a color gamut conversion program, and an integrated circuit.

  In order to realize color reproduction between different types of devices and different types of media, it is necessary to correct the difference in the color gamut of the input / output devices, and this technique is called color gamut conversion or color gamut compression expansion. For example, display output devices for displaying images include CRT (Cathode Ray Tube), PDP (Plasma Display Panel), LCD (Liquid Crystal Display), panels such as projectors, and the like. These have different reproducible color gamuts. For this reason, for example, when an image signal of a certain color gamut is displayed on a display output device of a certain color gamut, it is necessary to correct the image signal to a color gamut corresponding to the display output device.

  In order to correct the difference in color gamut, device-specific signal values represented by R, G, and B, for example, XYZ, L by CIE (Commission International de l'Eclairage) are used. It is common to convert to a color space that does not depend on a display output device such as * a * b * and L * u * v *, and to perform compression and expansion in that color space.

Regarding the expansion of the color gamut, for example, when the color reproduction range on the output side is wider than the color reproduction range on the input side, the color reproduction range on the input side is expanded according to the ratio of the color reproduction range on the input side and the output side. As described above, a method of enlarging and outputting the value of the color system of the input image (Patent Document 1), and as an expansion method, the color coordinates are expressed by luminance expansion (L *) and saturation (C *) by a linear expansion equation. A method is disclosed in which a color attribute is extended and converted, and control is performed so that it does not fall outside the color gamut of the device (Patent Document 2).
Japanese Patent Laid-Open No. 03-158075 JP 2003-153027 A

  Although linear color gamut expansion in a uniform color space such as L * a * b * and L * u * v * as in the above example is desirable in terms of maintaining natural color and performing color gamut expansion. In order to extend, boundary information of the extended color reproduction range is required. The boundary information of the color reproduction range becomes a three-dimensionally complicated shape when converted into L * a * b * and L * u * v * spaces.

  In Patent Document 1, for this reason, a result calculated using boundary information is held in a lookup table (hereinafter referred to as LUT). As an example, it is described that an LUT of data of 32 × 32 × 32 = 32768 is used in combination of Ye, Mg, and Cy.

  In Patent Document 2, for example, after being converted into a space of L * a * b *, it is linearly expanded. At this time, as described in the document, luminance and saturation color attribute information is a device having a wide color gamut. Is controlled so that it does not fall outside the color gamut. For this reason, it is necessary to have device gamut information in the L * a * b * space, but the gamut boundary in the L * a * b * space has a complex three-dimensional shape. Control that does not go out of the color gamut with the device is complicated.

  In this way, linear color gamut expansion in a uniform color space such as L * a * b * and L * u * v * requires boundary information of the color reproduction range, and since this boundary information has a large amount of information, the LUT When it is realized by hardware, the scale becomes large.

  Further, since boundary information is required, correction and adjustment cannot be easily performed. Depending on the image source, if the skin color or the like faithfully reproduces the original color gamut, it may not necessarily be a desired color and correction may be required, but this is also difficult. For example, in an example where the portion with high saturation is linearly expanded, the characteristic change of the portion with low saturation is related to the boundary between the portion with low saturation and the portion with high saturation, and this boundary is the color gamut of the output. Since it is related to boundary information, it cannot be easily corrected or adjusted. Also, when dealing with different devices, boundary information corresponding to the output device is required, and boundary information with a large amount of information is changed, so that it is not possible to easily deal with different devices.

  To achieve the above object, the present invention provides a color gamut conversion device that converts color data of a first color gamut into color data of a second color gamut, and corrects the color data of the first color gamut. A color gamut conversion unit that controls a color gamut conversion characteristic by a signal, and color data of the second color gamut by combining the color data of the first color gamut and the color data converted by the color gamut conversion unit. And a synthesizing unit for outputting.

  Here, the color gamut conversion unit includes an inverse gamma conversion unit, a matrix calculation unit that performs matrix calculation on the output of the inverse gamma conversion unit, and a gamma conversion unit, and the matrix calculation unit outputs the correction signal to the correction signal. Accordingly, the color gamut may be converted into a color gamut between the first color gamut and the second color gamut.

  A combining unit that detects a region based on hue, saturation, and brightness from the color data of the first color gamut; and the color data converted by the color gamut conversion unit and the color data converted by the color gamut conversion unit; An area detection unit that calculates a mixing ratio of the first color gamut, and a mixing unit that mixes the color data of the first color gamut and the color data output converted by the color gamut conversion unit based on the mixing ratio. It may be characterized by that.

  Further, the above invention can be realized as a color conversion device, a program for operating these on a processing device such as a CPU, an integrated circuit having the above configuration in a functional unit, etc., and a more generalized above operation principle. It can be realized as the color conversion method used.

  As described above, according to the color gamut conversion device and the like according to the present invention, since the color gamut boundary information that requires a lot of information is not used in color gamut expansion, an LUT having a large scale is not necessarily required.

  In addition, since it is a combination of input color data and color data that has undergone color gamut conversion that does not change relative to each other, natural color gamut conversion that does not change the color of skin color and other colors is possible, and correction is also possible at the same time. It is also possible to control the color gamut conversion characteristics by the signal. As a result, it is possible to perform natural color gamut conversion to a desired color in an area that is not expanded including skin color.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, in each following embodiment, the same code | symbol is attached | subjected about the same component.

<< First Embodiment >>
A color gamut conversion device according to a first embodiment will be described with reference to FIGS.

  FIG. 1 is a block diagram showing a configuration of a color gamut conversion device 10 according to the first embodiment of the present invention. This color gamut conversion device is provided with a color gamut conversion unit 11 that receives image data of moving images such as video and photographs or still image data as input color signals such as RGB, and converts the input color signals into a predetermined color gamut. The synthesizer 12 combines the output of the gamut converted color gamut converter and the input color signal at a predetermined ratio, and the correction signal generator 13 generates a correction signal from the input color signal. The output color data is output to a display device for displaying colors, such as a display or a printer.

  FIG. 2 is a block diagram showing the configuration of the color gamut conversion device 20 according to the first embodiment of the present invention. This color gamut conversion device is an example in which the synthesis unit 12 in FIG. 1 is configured by an area detection unit 21 and a mixing unit 22.

  Hereinafter, the color gamut conversion device according to the first embodiment will be described with reference to FIG. 2 will be described with reference to FIGS. 3 to 6, and then the operation of the color gamut conversion device of FIG. 2 will be described.

  FIG. 3 is a block diagram showing a configuration of the color gamut conversion unit according to the first embodiment of the present invention, and is a configuration example of the color gamut conversion unit 11 of FIGS. 1 and 2. The color gamut conversion unit in FIG. 3 includes an inverse gamma conversion unit 31, a matrix calculation unit 32, and a gamma conversion unit 33. A gamma-corrected RGB signal is input, converted to an optically linear signal by the inverse gamma conversion unit 31, 3 × 3 matrix calculation is performed by the matrix calculation unit 32 on the linear signal, and the gamma conversion unit 33 performs the 3 × 3 matrix calculation. The RGB signal is again subjected to gamma correction processing. The matrix calculation unit 32 can be controlled by a correction signal. The correction signal is Kc, and Kc is normalized and takes a value of 0 to 1.

  The matrix calculation unit 32 regards the input RGB signal as RGB corresponding to the input color gamut, converts it to data in the XYZ input color gamut space, and then reverses the XYZ value as RGB of the output device color gamut. It corresponds to converting. If conversion from RGB to XYZ and reverse conversion from XYZ to RGB are performed collectively, conversion from RGB to RGB results. If the input RGB is Ri, Gi, Bi, the output RGB is Ro, Go, Bo, and the 3 × 3 matrix coefficients are A11 to A33, they can be expressed as in equation (1).

  Here, the matrix coefficients A11 to A33 are controlled by the correction signal Kc.

  FIG. 4 is a diagram illustrating a color gamut characteristic example of the color gamut conversion unit 11 according to the first embodiment of the present invention. The inner triangle of (1) indicates the BT.709 color gamut. The outermost triangle (2) indicates an output device color gamut example. The triangle of (3) is located between the triangles of (1) and (2), and is an example of the display color gamut on the output device when the color gamut conversion means is controlled by the correction signal, and the BT.709 color gamut This is an example of a color gamut expanded by 30% toward the output device color gamut (corresponding to the correction signal Kc = 0.3). Hereinafter, these color gamuts in FIG. 4 are represented as a color gamut (1), a color gamut (2), and a color gamut (3).

  As an operation of the color gamut conversion unit here, first, the input BT.709 color gamut data of the color gamut (1) is faithfully output as the BT.709 color gamut in the output device of the color gamut (2). The color gamut conversion will be described.

  The conversion from RGB to XYZ is calculated from Rxi, Ryi, Gxi, Gyi, Bxi, Byi that are x, y data of chromaticity points of RGB colors of the BT.709 gamut on the input side of the gamut (1). Is done. Next, the conversion from XYZ to RGB is calculated from Rxd, Ryd, Gxd, Gyd, Bxd, Byd which are x, y data of RGB chromaticity points of the output device gamut of the gamut (2). . If the conversion from RGB to XYZ and the inverse conversion from XYZ to RGB are performed at once, a 3 × 3 matrix operation is performed, and the coefficients at this time are A11c to A33c.

  Matrix calculation is performed using the matrix coefficients A11c to A33c thus obtained, and color gamut conversion is performed together with the previous and subsequent inverse gamma conversion and gamma conversion. With this matrix, if the output device color gamut is the BT.709 color gamut, the input BT.709 color gamut data takes a compressed value as a signal, but the output device of the color gamut (2). Since the color gamut is wider than the BT.709 color gamut, it is expanded and displayed as a BT.709 color gamut on the output device of the color gamut (2), and can be faithfully reproduced and output.

  A color gamut to be displayed on the output device is referred to as a target color gamut, and in this case, the target color gamut is a BT.709 color gamut.

  If the gamut conversion is not performed, and if the BT.709 gamut input signal is displayed on the output device of the BT.709 gamut, the input BT.709 gamut is faithfully reproduced, but the gamut (2 ), The data of the BT.709 color gamut is expanded and displayed in the output device color gamut of the color gamut (2) wider than the BT.709 color gamut.

  When gamut conversion is not performed and displayed on the output device of the gamut (2) device gamut, for example, an input skin color is displayed as a reddish skin color, but gamut conversion is performed Even when the input skin color is displayed on the output device of the device color gamut of the color gamut (2), the skin color is not reddish and is displayed as the same color. Generally, not only the skin color but also the color when the above gamut conversion is performed on the input signal and displayed on the output device of the color gamut (2) is the color when the input signal is directly displayed on the output device of the color gamut (1). Is equivalent to

  Next, a case where the correction signal Kc = 0.3 will be described as an example of the control operation using the correction signal of the color gamut conversion unit. This is a color obtained by extending the input BT.709 color gamut data of the color gamut (1) to the output device of the color gamut (2) by 30% toward the color gamut (2) based on the color gamut (1). This corresponds to color gamut conversion when output to the gamut (3). The x, y data of the chromaticity point of the gamut (3) is obtained by correcting the x, y data of the chromaticity point of the gamut (1) and the x, y data of the chromaticity point of the gamut (2) with the correction signal Kc. It is a weighted average value.

  In the conversion from RGB to XYZ, the input signal is regarded as a signal in the color gamut (3) here, and Rxm which is x and y data of chromaticity points of each color of RGB in the color gamut (3). , Rym, Gxm, Gym, Bxm, Bym. Conversion from XYZ to RGB is the same as described above, and Rxd, Ryd, Gxd, Gyd, Bxd, Byd, which are x and y data of RGB chromaticity points in the output device gamut of the gamut (2). It is calculated from. If the conversion from RGB to XYZ and the inverse conversion from XYZ to RGB are performed at once, a 3 × 3 matrix operation is obtained, and the matrix coefficients at this time are set to matrix coefficients A11m to A33m.

In the above description, the matrix coefficients A11m to A33m are obtained from the chromaticity point of the color gamut (3). The target color gamut is the matrix coefficient of the BT.709 color gamut, and the target color gamut is the matrix coefficient of the output device. It is also possible to use a value obtained by performing a mixing operation using Kc. The matrix coefficients having a target color gamut of BT.709 are assumed to be A11i to A33i.
In this case, one of A11i, A22i, and A33i is 0.
The matrix coefficients of the output device with the target color gamut are A11d to A33d.
A11m to A33m are obtained by performing a mixing operation on these matrix coefficients using Kc as follows.

A11m = (1-Kc) * A11i + Kc * A11d
A12m = (1-Kc) * A12i + Kc * A12d
・
・
A33m = (1-Kc) * A33i + Kc * A33d
By performing matrix calculation using the matrix coefficients A11m to A33m obtained in this way and performing color gamut conversion together with the previous and subsequent inverse gamma conversion and gamma conversion, the input BT.709 color gamut data is converted into color. The color gamut (3) can be displayed on the gamut (2) output device.
With the method as described above, the color gamut conversion means sets the color gamut displayed on the output device as the target color gamut between the color gamut (1) and the color gamut (2) according to the correction signal Kc. Can be controlled.

  FIG. 5 is a block diagram showing a configuration of the region detection unit according to the first embodiment of the present invention, and is a configuration example of the region detection unit 21 of FIG. 5 includes an inverse gamma conversion unit 31, an XYZ conversion unit 51, an L * a * b * conversion unit 52, an HSL conversion unit 53, an HSL region setting unit 54, and a mixture ratio calculation unit 55.

  The inverse gamma conversion unit 31 receives a gamma-corrected RGB signal and converts it to an optically linear RGB signal. This optically linear RGB signal is converted into XYZ in a device-independent color space by an XYZ converter 51. Further, the XYZ is converted into an L * a * b * space which is a uniform color space by the L * a * b * conversion unit 52. The conversion characteristic to the L * a * b * space is shown in Equation (2).

  The lightness L of the input L * a * b * remains unchanged, and a and b are converted into hue H and saturation S as shown in Expression (3) by the HSL conversion unit 53.

  The HSL region setting unit 54 performs region setting for the input hue H, saturation S, and lightness L. A color area in which the color tone is not desired to be changed as much as possible is hereinafter referred to as a storage color area. The color area that is not, that is, the color area to be expanded is hereinafter referred to as an expansion area. The output of the area detection means is a value between 0 and 1, and when the output of the area detection means is 0, it is a saved color area, and when the output of the area detection means is 1, it is an extended area.

  For example, the hue H is divided into six hue areas centered on the main colors of red R, yellow Ye, green G, cyan Cy, blue B, and magenta Mg. It is assumed that the saturation threshold value Sth is set for each hue region.

  The saturation threshold Sth is a threshold for dividing the storage area and the expansion area, takes a value of 0 to 1 normalized by the maximum saturation value of the hue area, and the saturation is smaller than the saturation threshold Sth. It corresponds to a storage area, and when it is large, it corresponds to an expansion area.

  The mixing ratio calculation unit 55 outputs the mixing ratio r with respect to the saturation threshold value Sth set for each hue region in the HSL region setting unit 54. FIG. 6 shows the relationship between the saturation S, the saturation threshold Sth, and the mixture ratio r in the mixture ratio calculation unit 55. This figure shows the relationship between the saturation S and the mixing ratio r in a certain hue region, and is an example using a sigmoid function as a function. The relationship between the saturation S and the mixing ratio r is such that r is close to 0 when the saturation S is small, increases as it approaches the saturation threshold Sth, and r = 0.5 at the saturation threshold Sth. As degree S increases, it approaches 1. In FIG. 6, three cases where Sth is Sth1, Sth2, and Sth3 are shown as a solid line, a broken line, and a one-dot chain line, respectively. Here, Sth1 = 0.5, Sth2 = 0.6, and Sth3 = 0.4. A state in which these graphs Sth are translated in the saturation S direction is shown.

  In this embodiment, a sigmoid non-linear curve is used as a function of the synthesis ratio r, but it is also conceivable to use a linear straight line.

  In the above description, an example in which the saturation threshold Sth depends only on the hue H in dividing the storage color area and the extension area in the area detection has been described. When the lightness L is small, it is conceivable to decrease the saturation threshold Sth.

  Various methods for obtaining the correction signal are conceivable, and an external signal may be used as the correction signal. For example, the source of a movie is different in color from that of an on-air source that is normally broadcast, so many TVs often use a mode and a cinema mode, and this mode information is used. Is also possible. Movie sources tend to be reddish compared to normal air-on-air sources. For this reason, in a movie source, even if the skin color faithfully reproduced in the above-described storage area is reproduced as a desired skin color in the display, the skin color may be reddish in the on-air source. Therefore, the correction signal is changed between the normal mode and the cinema mode, the correction signal is set to 0 in the cinema mode, the correction signal is set to, for example, 0.5 in the normal mode, and the color gamut is slightly changed even in the storage area in the normal mode. By adjusting so as to be wide, it becomes possible to obtain a good skin color in both a movie source and a normal source.

  FIG. 7 is a block diagram illustrating a configuration example of the correction signal generation unit 13 according to the first embodiment of the present invention. The correction signal detection unit 13 in FIG. 7 is an example in the case of detecting a correction signal from an input signal. The correction signal detection unit 13 of FIG. 7 includes an inverse gamma conversion unit 31, an XYZ conversion unit 51, an L * a * b * conversion unit 52, an HSL conversion unit 53, and a correction signal output unit 71.

  The inverse gamma conversion unit 31, the XYZ conversion unit 51, the L * a * b * conversion unit 52, and the HSL conversion unit 53 are the same as those described in the description of the region detection unit in FIG.

  The correction signal output unit 71 sets a range for each of the hue H, saturation S, and lightness L output from the HSL conversion unit 53, sets the range as a correction region, and outputs 1 except for the correction region. A value between 0 and 1 is output in the area. As a simple example, an example in which the correction signal has a constant value in the correction region can be considered. An example in which the correction signal is a function with respect to hue H, saturation S, and lightness L is also conceivable. It is also conceivable to use a function that takes a value close to 0 at the center of the correction area and takes a value close to 1 as it approaches the periphery.

  The overall operation will be described based on the description of the individual components of the color gamut conversion apparatus shown in FIG. The region detection unit 21 outputs the mixture ratio r with respect to the set saturation threshold value Sth by the process as shown in FIG. With the mixing ratio r, the mixing unit 22 mixes the input color signal and the output of the color gamut conversion unit 11 by the mixing unit 22. Here, the mixing ratio r is a ratio for mixing the input color signal with respect to the output of the color gamut conversion unit 11. For example, when r = 0, only the output of the color gamut conversion unit 11 is provided, which corresponds to a storage area. When r = 1, only the input color signal is obtained, which corresponds to the extended region. Colors that cause a sense of incongruity when the color changes, such as skin color, are stored color regions, the output ratio of the color gamut conversion unit 11 is increased, and conversely, the color gamut boundary of the output device and its neighboring colors are expanded. The area is set so that the ratio of the input color signal is high.

  Further, the characteristics of the color gamut conversion unit 11 are controlled by the correction signal generation unit 13. The correction signal is normally 0, but takes a value close to 1 depending on the situation. When the correction signal is 0, the characteristics of the color gamut conversion unit 11 are such that the input color gamut is faithfully reproduced in the storage area. When the correction signal is 1, the characteristics of the color gamut conversion unit 11 are the same as those of the extended area in the storage area.

As the correction signal approaches 0 to 1, the characteristics of the color gamut conversion unit 11 are such that the converted color gamut becomes wider in the storage area.
The storage area is basically intended to faithfully reproduce the input color gamut even after conversion. For example, when the lightness L is low and the saturation L is low in the skin color, the color gamut is When faithfully reproduced, the desired skin color may not always be obtained. In such a region, the characteristics of the color gamut conversion unit 11 are changed by the correction signal generation means, and the output of the color gamut conversion unit 11 is wide color gamut. By controlling so that a desired skin color can be obtained.

(Second Embodiment)
A color gamut conversion device according to a second embodiment will be described with reference to FIGS.

  In the first embodiment and the present embodiment, the output of the correction value calculated by the correction signal generation unit 13 is input to the mixing unit 22, the color gamut conversion unit 81 does not receive the correction signal, The difference is that the mixing unit 82 receives the correction signal. Since the other points are the same as those in the first embodiment, description thereof is omitted.

  FIG. 9 is a block diagram showing the configuration of the color gamut conversion unit 81 according to the second embodiment of the present invention. 9 includes an inverse gamma conversion unit 31, a matrix calculation unit 92, and a gamma conversion unit 33. An RGB signal is input, converted into an optically linear signal by the inverse gamma conversion unit 31, 3 × 3 matrix calculation is performed on the linear signal by the matrix calculation unit 92, and gamma correction processing is performed by the gamma conversion 33 unit. Signal. The content of the color gamut conversion unit 11 according to the first embodiment is different from that shown in FIG. 3 in that the matrix calculation unit 92 does not receive a correction signal.

  The region detection unit 21 outputs the mixture ratio r with respect to the set saturation threshold value Sth by the process as shown in FIG. Based on this mixing ratio r, the mixing unit 82 mixes the input color signal and the output of the color gamut conversion unit 81 by the mixing unit 82. Here, the mixing ratio r is a ratio for mixing the input color signal with respect to the output of the color gamut conversion unit 81. For example, r = 0 corresponds to the storage area and only the output of the color gamut conversion unit 81, and r = 1 corresponds to the expansion area and only the input color signal. A color that causes a sense of incongruity when the color changes, such as skin color, is regarded as a storage color region, and the output ratio of the color gamut conversion unit 81 is increased. To increase the ratio.

Further, the characteristic of the mixing ratio r is controlled by the correction signal generator 13. The correction signal is Kc. It is assumed that the mixing ratio r when the correction signal Kc = 0 is r = r (S) as a function of the saturation S. The mixing ratio r is a function of the correction signal Kc, for example, r = r (S) × (1−Kc) + Kc.
The correction signal Kc is normally 0, but takes a value close to 1 depending on the situation. When the correction signal Kc is 0, the characteristics are such that the input color gamut is faithfully reproduced in the storage area. When the correction signal Kc takes a value close to 1, the storage area has a characteristic that reproduces a color gamut wider than the input color gamut.

  In FIG. 10, the cases where Kc is 0, 0.2, and 0.4 are shown as graphs of a solid line, a broken line, and an alternate long and short dash line, respectively. It shows how the mixing ratio increases in the area corresponding to the storage area due to the change in Kc. By setting it as such a function, the level of the preservation | save color area | region of low saturation can be changed.

  The storage area described above is intended to faithfully reproduce the input color gamut even after conversion. For example, when the lightness L is low and the saturation S is low in skin color, the color gamut is faithfully reproduced. In such a case, the desired skin color may not always be obtained. In such a region, the characteristics of the mixing ratio r are changed by the correction signal generation unit 13, and the input color with respect to the output of the gamut conversion unit 81 also in the storage region. By increasing the signal mixing ratio, the skin color is controlled to have a wide color gamut, and a desired skin color can be obtained.

  The above embodiment can also be executed by a hardware circuit such as an LSI, a program using an arithmetic device and a memory, and software.

  According to the color gamut conversion apparatus and method of the present invention, it is not always necessary to perform an LUT, and color gamut conversion can be performed while maintaining a natural hue, and adjustment and correction can be easily performed. Since it can be easily handled, it is useful for video displays such as TVs, projectors, printers, digital cameras, and the like.

1 is a block diagram showing a configuration of a color gamut conversion device 10 according to a first embodiment. 1 is a block diagram showing a configuration of a color gamut conversion device 20 according to a first embodiment. 1 is a block diagram showing a configuration of a color gamut conversion unit according to a first embodiment. The figure which shows the color gamut characteristic example of the color gamut conversion part which concerns on this Embodiment The block diagram which shows the structure of the area | region detection part which concerns on this Embodiment. The figure which shows the mixing ratio of the mixing part which concerns on 1st Embodiment The block diagram which shows the structure of the correction signal generation part which concerns on this Embodiment The block diagram which shows the structure of the color gamut conversion apparatus 30 which concerns on 2nd Embodiment. The block diagram which shows the structure of the color gamut conversion part which concerns on 2nd Embodiment. The figure which shows the mixing ratio of the mixing part which concerns on 2nd Embodiment

11, 81 Color gamut conversion unit 12 Composition unit 13 Correction signal generation unit 21 Region detection unit 22, 82 Mixing unit 31 Inverse gamma conversion unit 32, 92 Matrix calculation unit 33 Gamma conversion unit 51 XYZ conversion unit 52 L * a * b * Conversion unit 53 HSL conversion unit 54 HSL region setting unit 55 Mixing ratio calculation unit 71 Correction signal output unit

Claims (9)

A color gamut conversion device that converts color data of a first color gamut into color data of a second color gamut,
A color gamut conversion unit that controls color gamut conversion characteristics of the color data of the first color gamut using a correction signal;
A color gamut comprising: a color synthesizing unit that synthesizes the color data of the first color gamut and the color data converted by the color gamut conversion unit and outputs color data of the second color gamut. Conversion device. The color gamut conversion unit includes an inverse gamma conversion unit, a matrix calculation unit that performs matrix calculation on the output of the inverse gamma conversion unit, and a gamma conversion unit,
The color gamut conversion device according to claim 1, wherein the matrix calculation unit converts the color gamut between the first color gamut and the second color gamut according to the correction signal. 3. The matrix calculation unit performs calculation using a coefficient obtained by interpolating a first matrix coefficient serving as the first color gamut and a second matrix coefficient serving as the second color gamut. The color gamut conversion device described in 1. The combining unit detects a region based on hue, saturation, and brightness from the color data of the first color gamut, and the color data of the first color gamut and the color data converted by the color gamut conversion unit An area detector for calculating the mixing ratio;
The mixing unit for mixing the color data of the first color gamut and the color data output converted by the color gamut conversion unit based on the mixing ratio. Color gamut converter. The said area | region detection part makes the ratio which synthesize | combines the color data output converted by the said color gamut conversion part low, as the saturation of the color data of the said 1st color gamut becomes high. The color gamut conversion device described. The color gamut conversion device according to claim 1, wherein the correction signal is input from outside the device. The color gamut conversion device according to claim 1, further comprising a correction signal generation unit that outputs a correction signal based on hue, saturation, and brightness of the color data of the first color gamut. A color gamut conversion device that converts color data of a first color gamut into color data of a second color gamut,
A color gamut conversion unit that converts the color gamut of the first color gamut into the second color gamut;
A region is detected from the color data of the first color gamut based on hue, saturation, and brightness, and a mixing ratio between the color data of the first color gamut and the color data converted by the color gamut conversion unit is calculated. A color gamut comprising: an area detection unit; a correction unit that mixes the color data of the first color gamut and the color data converted by the color gamut conversion unit based on the correction signal and the mixing ratio; Conversion device. The color gamut conversion unit according to claim 8, wherein the color gamut conversion unit includes an inverse gamma conversion unit, a matrix calculation unit that performs matrix calculation on an output of the inverse gamma conversion unit, and a gamma conversion unit. apparatus.

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