Primary color conversion method and converter thereof, display control method, and display device
Disclosed is a primary color conversion method, which may expand primary color signals that are applicable to a display device. The primary color conversion method includes: acquiring color coordinates and a brightness value of a first color in a first color gamut having M primary colors according to gray-scale values of the M primary colors corresponding to the first color; and mapping the color coordinates and the luminance value of the first color in the first color gamut to color coordinates and a brightness value of a second color corresponding to the first color in a second color gamut having N primary colors. 3≤M, 3≤N, M is different from N, and M and N are positive integers.
1. A primary color conversion method, comprising:
obtaining color coordinates and a luminance value of a first color in a first color gamut having M primary colors according to gray-scale values of the M primary colors corresponding to the first color;
mapping the color coordinates and the luminance value of the first color in the first color gamut to color coordinates and a luminance value of a second color corresponding to the first color in a second color gamut having N primary colors, which includes:
obtaining a maximum luminance value Y max (x, y) of the first color in the first color gamut;
obtaining a maximum luminance value Y 1max (x 1 , y 1 ) of the second color in the second color gamut; and
obtaining a luminance value Y 1 (x 1 , y 1 ) of the second color in the second color gamut according to a formula:
Y
(
x
,
y
)
Y
max
(
x
,
y
)
=
Y
1
(
x
1
,
y
1
)
Y
1
max
(
x
1
,
y
1
)
,
wherein Y(x, y) is a luminance value of the first color in the first color gamut;
3 is less than or equal to M, 3 is less than or equal to N, M is different from N, and M and N are both positive integers.
2. The primary color conversion method according to claim 1 , wherein mapping the color coordinates and the luminance value of the first color in the first color gamut to color coordinates and a luminance value of a second color corresponding to the first color in a second color gamut having N primary colors, further includes:
mapping a color coordinate point A of the first color in the first color gamut to a color coordinate point A 1 of the second color corresponding to the first color in the second color gamut having N primary colors,
a process of mapping the color coordinate point A of the first color to the color coordinate point A 1 of the second color being equal scale mapping.
3. The primary color conversion method according to claim 2 , wherein mapping a color coordinate point A of the first color in the first color gamut to a color coordinate point A 1 of the second color corresponding to the first color in the second color gamut having N primary colors, a process of mapping the color coordinate point A of the first color to the color coordinate point A 1 of the second color being equal scale mapping, includes:
drawing a mapping line segment in a chromaticity diagram, the mapping line segment extending from a color coordinate point D of a white color to the color coordinate point A of the first color;
obtaining a first intersection point P between an extension line of the mapping line segment and a boundary of the first color gamut, and a second intersection point P 1 between the extension line of the mapping line segment and a boundary of the second color gamut; and
obtaining the color coordinate point A 1 of the second color according to a formula:
D
A
D
P
=
D
A
1
D
P
1
,
wherein
DA is a length of a line segment between the color coordinate point D of the white color and the color coordinate point A of the first color; DP is a length of a line segment between the color coordinate point D of the white color and the first intersection point P; DA 1 is a length of a line segment between the color coordinate point D of the white color and the color coordinate point A 1 of the second color; and DP 1 is a length of a line segment between the color coordinate point D of the white color and the second intersection point P 1 .
4. The primary color conversion method according to claim 1 , wherein obtaining a maximum luminance value Y 1max (x 1 , y 1 ) of the second color in the second color gamut, includes:
obtaining a three-dimensional diagram of the second color gamut in a color space; and
obtaining, along a direction of a luminance coordinate axis of the color space, a point, which corresponds to the color coordinate point of the second color in the second color gamut, on a boundary of the three-dimensional diagram of the second color gamut, a value of the point on the luminance coordinate axis being a maximum luminance value Y 1max (x 1 , y 1 ) of the second color in the second color gamut.
5. The primary color conversion method according to claim 1 , wherein obtaining a maximum luminance value Y max (x, y) of the first color in the first color gamut, includes:
obtaining tristimulus values of the first color in the first color gamut according to gray-scale values of the M primary colors corresponding to the first color and a conversion matrix of the first color gamut, and using a Y value of the tristimulus values of the first color in the first color gamut as a luminance value Y(x, y) of the first color in the first color gamut, and
obtaining the maximum luminance value Y max (x, y) of the first color in the first color gamut according to the luminance value Y(x, y) of the first color in the first color gamut, wherein a ratio of the maximum luminance value Y max (x, y) of the first color in the first color gamut to the luminance value Y(x, y) of the first color in the first color gamut is equal to a ratio of a maximum value within a gray-scale range to a maximum value of gray-scale values of the M primary colors corresponding to the first color.
6. The primary color conversion method according to claim 1 , wherein obtaining a maximum luminance value Y max (x, y) of the first color in the first color gamut, includes:
obtaining a three-dimensional diagram of the first color gamut in a color space; and
obtaining, along a direction of a luminance coordinate axis of the color space, a point, which corresponds to the color coordinate point of the first color in the first color gamut, on a boundary of the three-dimensional diagram of the first color gamut, a value of the point on the luminance coordinate axis being a maximum luminance value Y max (x, y) of the first color in the first color gamut.
7. The primary color conversion method according to claim 1 , wherein obtaining color coordinates of a first color in the first color gamut, includes:
obtaining tristimulus values of the first color in the first color gamut according to gray-scale values of the M primary colors corresponding to the first color and a conversion matrix of the first color gamut; and
obtaining color coordinates of the first color in the first color gamut according to the tristimulus values of the first color in the first color gamut.
8. The primary color conversion method according to claim 1 , wherein M is less than N.
9. A display control method for controlling a display device to perform display, wherein the display device includes a plurality of pixel units, each pixel unit includes sub-pixels of N primary colors, 3 is less than or equal to N, and N is a positive integer, and the display control method comprises:
obtaining gray-scale values of sub-pixels of M primary colors corresponding to a pixel unit from an original image, the M primary colors of the sub-pixels being in one-to-one correspondence with M primary colors of a first color gamut, wherein the original image corresponds to display signals with the M primary colors, 3 is less than or equal to M, M is different from N, and M and N are both positive integers;
using the primary color conversion method according to claim 1 to obtain a luminance value of a color to be displayed of the pixel unit in a second color gamut having N primary colors; and
obtaining gray-scale values of the sub-pixels of N primary colors in the pixel unit according to the luminance value of the color to be displayed of the pixel unit in the second color gamut, wherein the N primary colors of the sub-pixels are in one-to-one correspondence with the N primary colors of the second color gamut.
10. A computer device, comprising a memory and a processor, wherein the memory has stored thereon a computer program executable on the processor, and the computer program, when executed by the processor, implements the primary color conversion method according to claim 1 .
11. A non-transitory computer-readable storage medium storing a computer program that, when executed by a processor, implements the primary color conversion method according to claim 1 .
12. A primary color converter for performing primary color conversion by using the primary color conversion method according to claim 1 , wherein the primary color converter comprises a first data processor and a second data processor;
the first data processor is configured to obtain color coordinates and a luminance value of a first color in a first color gamut having M primary colors according to gray-scale values of the M primary colors corresponding to the first color; and
the second data processor is coupled to the first data processor, and the second data processor is configured to map the luminance value of the first color in the first color gamut to a luminance value of a second color corresponding to the first color in a second color gamut having N primary colors, wherein
3 is less than or equal to M, 3 is less than or equal to N, M is different from N, and M and N are both positive integers.
13. A display device, comprising a plurality of pixel units, wherein each pixel unit includes N sub-pixels, N is greater than or equal to 3, and N is a positive integer; and
the display device further comprises the primary color converter according to claim 12 .
14. A primary color conversion method, comprising:
obtaining color coordinates and a luminance value of a first color in a first color gamut having M primary colors according to gray-scale values of the M primary colors corresponding to the first color;
mapping the color coordinates and the luminance value of the first color in the first color gamut to color coordinates and a luminance value of a second color corresponding to the first color in a second color gamut having N primary colors, which includes:
drawing a mapping line segment in a chromaticity diagram, the mapping line segment extending from a color coordinate point D of a white color to a color coordinate point A of the first color;
obtaining a first intersection point P between an extension line of the mapping line segment and a boundary of the first color gamut, and a second intersection point P 1 between the extension line of the mapping line segment and a boundary of the second color gamut; and
obtaining a color coordinate point A 1 of the second color according to a formula:
D
A
D
P
=
D
A
1
D
P
1
,
the formula of mapping the color coordinate point A of the first color to the color coordinate point A 1 of the second color being equal scale mapping, wherein
DA is a length of a line segment between the color coordinate point D of the white color and the color coordinate point A of the first color; DP is a length of a line segment between the color coordinate point D of the white color and the first intersection point P; DA 1 is a length of a line segment between the color coordinate point D of the white color and the color coordinate point A 1 of the second color; and DP 1 is a length of a line segment between the color coordinate point D of the white color and the second intersection point P 1 ;
3 is less than or equal to M, 3 is less than or equal to N, M is different from N, and M and N are both positive integers.
15. A display control method for controlling a display device to perform display, wherein the display device includes a plurality of pixel units, each pixel unit includes sub-pixels of N primary colors, 3 is less than or equal to N, and N is a positive integer, and the display control method comprises:
obtaining gray-scale values of sub-pixels of M primary colors corresponding to a pixel unit from an original image, the M primary colors of the sub-pixels being in one-to-one correspondence with M primary colors of a first color gamut, wherein the original image corresponds to display signals with the M primary colors, 3 is less than or equal to M, M is different from N, and M and N are both positive integers;
using the primary color conversion method according to claim 14 to obtain color coordinates of a color to be displayed of the pixel unit in a second color gamut having N primary colors; and
obtaining gray-scale values of the sub-pixels of N primary colors in the pixel unit according to the color coordinates of the color to be displayed of the pixel unit in the second color gamut, wherein the N primary colors of the sub-pixels are in one-to-one correspondence with the N primary colors of the second color gamut.
16. A computer device, comprising a memory and a processor, wherein the memory has stored thereon a computer program executable on the processor, and the computer program, when executed by the processor, implements the primary color conversion method according to claim 14 .
17. A non-transitory computer-readable storage medium storing a computer program that, when executed by a processor, implements the primary color conversion method according to claim 14 .
18. A primary color converter for performing primary color conversion by using the primary color conversion method according to claim 14 , wherein the primary color converter comprises a first data processor and a second data processor;
the first data processor is configured to obtain color coordinates and a luminance value of a first color in a first color gamut having M primary colors according to gray-scale values of the M primary colors corresponding to the first color; and
the second data processor is coupled to the first data processor, and the second data processor is configured to map the color coordinates of the first color in the first color gamut to color coordinates of a second color corresponding to the first color in a second color gamut having N primary colors, wherein
3 is less than or equal to M, 3 is less than or equal to N, M is different from N, and M and N are both positive integers.
19. A display device, comprising a plurality of pixel units, wherein each pixel unit includes N sub-pixels, N is greater than or equal to 3, and N is a positive integer; and
the display device further comprises the primary color converter according to claim 18 .