GAMUT MAPPING

• US 20150213626A1
• Filed: 05/28/2014
• Published: 07/30/2015
• Est. Priority Date: 01/28/2014
• Status: Abandoned Application

• Current Assignee: InnoLux Corporation
• Original Assignee: InnoLux Corporation
• Inventors: Hekstra, Gerben
• Application Number:
  US14/288,499
• Publication Number:
  US 20150213626A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G09G 2300/0452 Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 3/2003 Display of colours specific for liquid crystal displays G09G3/3607
• CPC Class Codes: G09G 5/02 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 Class Codes: H04N 1/6058 Reduction of colour to a range of reproducible colours, e.g. to ink- reproducible colour gamut

Abstract

The present disclosure provides a gamut mapping method. In the gamut mapping method, a plurality of first color points of a first gamut of an image signal is mapped into a plurality of second color points of a second gamut. Each of the plurality of second color points is generated by multiplying each component value of the plurality of primary colors by a corresponding scaling factor. If at least one component value of the plurality of primary colors is zero, the larger a maximum component value of the plurality of primary colors is, the smaller the corresponding scaling factor is.

Claims

1. A gamut mapping method, comprising:

mapping a plurality of first color points of a first gamut of an image signal into a plurality of second color points of a second gamut, each of the plurality of first color points being composed of a plurality of primary colors,

wherein each of the plurality of second color points is generated by multiplying each component value of the plurality of primary colors by a corresponding scaling factor;

wherein if at least one component value of the plurality of primary colors is zero, the larger a maximum component value of the plurality of primary colors is, the smaller the corresponding scaling factor is.

2. The gamut mapping method as claimed in claim 1, wherein the first gamut is defined by red, green and blue primary colors, and the plurality of primary colors comprises red, green and blue primary colors.

3. The gamut mapping method as claimed in claim 2, wherein the second gamut is defined by red, green, blue and white primary colors, and the gamut mapping method further comprises:

determining the corresponding scaling factor based on minimum and maximum component values of the plurality of primary colors and a variable parameter equal to a ratio value of a maximum allowable component value of the white primary color to a maximum allowable component value of the red, green and blue primary colors of the second gamut.

4. The gamut mapping method as claimed in claim 3, wherein if the minimum and maximum component values of the plurality of primary colors are equal, the corresponding scaling factor is equal to 1.

5. The gamut mapping method as claimed in claim 4, wherein a scaling factor f of a first color point C is determined based on:

6. The gamut mapping method as claimed in claim 5, wherein if

7. The gamut mapping method as claimed in claim 6, wherein the variable parameter is not larger than an intrinsic ratio value of a maximum allowable component value of a white primary color to a maximum allowable component value of red, green and blue primary colors of a display device where the gamut mapping is applied and varied depending on any combination of ambient light condition, required output luminance of the display device and quality requirements of the display device.

8. The gamut mapping method as claimed in claim 7, wherein the fixed parameter is not larger than 1/(the intrinsic ratio value).

9. The gamut mapping method as claimed in claim 7, wherein the fixed parameter is equal to 0.45.

10. A gamut mapping apparatus, mapping a plurality of first color points of a first gamut of an image signal into a plurality of second color points of a second gamut, each of the plurality of first color points being composed of a plurality of primary colors, comprising:

a mapping unit, generating each of the plurality of second color points by multiplying each component value of the plurality of primary colors by a corresponding scaling factor,

wherein if at least one component value of the plurality of primary colors is zero, the larger a maximum component value of the plurality of primary colors is, the smaller the corresponding scaling factor is.

11. The gamut mapping apparatus as claimed in claim 10, wherein the first gamut is defined by red, green and blue primary colors, and the plurality of primary colors comprises red, green and blue primary colors.

12. The gamut mapping apparatus as claimed in claim 11, wherein t the second gamut is defined by red, green, blue and white primary colors, and the gamut mapping apparatus further comprises:

a scaling factor calculator, determining the corresponding scaling factor based on minimum and maximum component values of the plurality of primary colors and a variable parameter equal to a ratio value of a maximum allowable component value of the white primary color to a maximum allowable component value of the red, green and blue primary colors of the second gamut.

13. The gamut mapping apparatus as claimed in claim 12, wherein if the minimum and maximum component values of the plurality of primary colors are equal, the corresponding scaling factor is equal to 1.

14. The gamut mapping apparatus as claimed in claim 13, wherein the scaling factor calculator determines a scaling factor f of a first color point C based on:

15. The gamut mapping apparatus as claimed in claim 14, wherein if

16. The gamut mapping apparatus as claimed in claim 15, wherein the variable parameter is not larger than an intrinsic ratio value of a maximum allowable component value of a white primary color to a maximum allowable component value of red, green and blue primary colors of a display device where the gamut mapping is applied and varied depending on any combination of ambient light condition, required output luminance of the display device and quality requirements of the display device.

17. The gamut mapping apparatus as claimed in claim 16, wherein the fixed parameter is not larger than 1/(the intrinsic ratio value).

18. The gamut mapping apparatus as claimed in claim 16, wherein the fixed parameter is equal to 0.45.