Color gamut mapping method, color gamut mapping assembly, and display device

Patent metadata

Field	Value
Publication number	US-11900848-B2
Application number	US-202117996729-A
Country	US
Kind code	B2
Filing date	Mar 18, 2021
Priority date	Apr 20, 2020
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

Disclosed in the present application are a color gamut mapping method, a color gamut mapping assembly, and a display device. The method includes: obtaining a first connection line between a white point and an original point of the original color gamut; obtaining a first mapping point in a target color gamut of an intersection point of the first connection line and the original color gamut; obtaining a second connection line between a reference point in the original color gamut and the first mapping point; obtaining color coordinates of a second mapping point of the original point in the target color gamut; obtaining a luminance value of the second mapping point according to the original point and the white point; and obtaining grayscale values of the second mapping point according to the color coordinates and the luminance value of the second mapping point.

First claim

What is claimed is:

1. A color gamut mapping method, wherein the color gamut mapping method comprises following steps:
obtaining a first connection line between a white point of an original color gamut and an original point of the original color gamut;
obtaining a first mapping point in a target color gamut of an intersection point of the first connection line and the original color gamut;
obtaining a second connection line between a reference point in the original color gamut and the first mapping point;
obtaining color coordinates of a second mapping point of the original point in the target color gamut according to the white point, the reference point, the original point, the intersection point, and the second connection line;
obtaining a luminance value of the second mapping point according to the original point and the white point; and
obtaining grayscale values of the second mapping point according to the color coordinates and the luminance value of the second mapping point.

2. The color gamut mapping method as claimed in claim 1 , wherein the step of obtaining the color coordinates of the second mapping point of the original point in the target color gamut according to the white point, the reference point, the original point, the intersection point, and the second connection line comprises:
obtaining a first distance from the reference point to the original point if the original point is not between the white point and the reference point;
obtaining a second distance from the reference point to the intersection point;
obtaining a first ratio of the first distance to the second distance;
obtaining the color coordinates of the second mapping point based on the first ratio and the second connection line; and
determining that the color coordinates of the second mapping point are the color coordinates of the original point if the original point is between the white point and the reference point.

3. The color gamut mapping method as claimed in claim 2 , wherein the step of obtaining the color coordinates of the second mapping point based on the first ratio and the second connection line comprises: obtaining the color coordinates of the second mapping point through equal-proportional mapping according to the first ratio and the second connection line.

4. The color gamut mapping method as claimed in claim 2 , wherein the step of obtaining the color coordinates of the second mapping point based on the first ratio and the second connection line comprises:
obtaining a degree of aggregation based on the first ratio;
obtaining a position of the second mapping point on the second connection line according to the degree of aggregation; and
obtaining the color coordinates of the second mapping point according to the position of the second mapping point on the second connection line, wherein the second connection line is a distribution curve.

5. The color gamut mapping method as claimed in claim 1 , wherein the step of obtaining the first mapping point in the target color gamut of the intersection point of the first connection line and the original color gamut comprises:
obtaining the intersection point of the first connection line intersecting the original color gamut;
obtaining a position of the intersection point on a boundary line of the original color gamut;
obtaining a boundary line of the target color gamut corresponding to the boundary line of the original color gamut at the intersection point; and
obtaining the first mapping point based on the position of the intersection point on the boundary line of the original color gamut and the boundary line of the target color gamut.

6. The color gamut mapping method as claimed in claim 1 , wherein the second connection line is a curve, the second connection line is tangent to the first connection line, and the second connection line is tangent to a boundary line of the target color gamut.

7. The color gamut mapping method as claimed in claim 6 , wherein the second connection line is an arc curve.

8. The color gamut mapping method as claimed in claim 1 , wherein the color gamut mapping method further comprises:
obtaining the reference point based on the white point and the intersection point.

9. The color gamut mapping method as claimed in claim 8 , wherein the step of obtaining the reference point based on the white point and the intersection point comprises:
obtaining a third distance from the white point to the intersection point;
obtaining the reference point based on a preset ratio, the third distance, and the white point.

10. The color gamut mapping method as claimed in claim 9 , wherein the preset ratio is greater than or equal to 0 and less than or equal to 1, wherein the preset ratio is equal to a ratio of a distance from the reference point to the white point to a distance from the white point to the intersection point.

11. The color gamut mapping method as claimed in claim 1 , wherein the step of obtaining the luminance value of the second mapping point according to the original point and the white point comprises:
obtaining a first maximum luminance value of the white point in the original color gamut and a second maximum luminance value of a white point in the target color gamut;
obtaining the luminance value of the second mapping point based on a luminance value of the original point, the first maximum luminance value, and the second maximum luminance value.

12. The color gamut mapping method as claimed in claim 11 , wherein the step of obtaining the luminance value of the second mapping point based on the luminance value of the original point, the first maximum luminance value, and the second maximum luminance value comprises:
obtaining a second ratio of the luminance value of the original point to the first maximum luminance value;
obtaining the luminance value of the second mapping point based on the second ratio and the second maximum luminance value.

13. The color gamut mapping method as claimed in claim 1 , wherein the reference point is a non-fixed point or a plurality of non-fixed points preset in the original color gamut.

14. The color gamut mapping method as claimed in claim 1 , wherein the white point of the original color gamut is located at a same position in the color coordinates as a white point of the target color gamut.

15. The color gamut mapping method as claimed in claim 2 , wherein after the step of determining that the color coordinates of the second mapping point are the color coordinates of the original point if the original point is between the white point and the reference point, the color gamut mapping method further comprises:
adjusting the color coordinates of the second mapping point according to the luminance value of the second mapping point, so that an actual luminance value of the second mapping point is consistent with a calculated luminance value of the second mapping point.

16. The color gamut mapping method as claimed in claim 1 , wherein the step of obtaining the grayscale values of the second mapping point according to the color coordinates and the luminance value of the second mapping point comprises:
calculating tri-stimulus values of the second mapping point based on the color coordinates and the luminance value of the second mapping point and an electro-optical conversion curve; and
converting the tri-stimulus values of the second mapping point into corresponding grayscale values.

17. The color gamut mapping method as claimed in claim 1 , wherein the step of obtaining the grayscale values of the second mapping point according to the color coord

Assignees

• Shenzhen Tcl Digital Tech Ltd

Inventors

• Chen Lin
• Xia Daxue
• Xie Renli

Classifications

• G09G3/2003 Primary

  Display of colours (specific for liquid crystal displays G09G3/3607) · CPC title

• G09G2320/0666

  for control of colour parameters, e.g. colour temperature · CPC title

• G09G2340/06

  Colour space transformation · CPC title

• G09G5/02 Primary

  characterised by the way in which colour is displayed {(details of colour display specific for CRTs G09G1/28; specific for flat matrix panels other than liquid crystal displays G09G3/2003; specific for liquid crystal displays G09G3/3607)} · CPC title

• G09G5/026 Primary

  Control of mixing and/or overlay of colours in general (G09G5/022 and G09G5/024 take precedence) · CPC title