Method and apparatus for converting grayscale, and display device

Patent metadata

Field	Value
Publication number	US-10916173-B2
Application number	US-201916397185-A
Country	US
Kind code	B2
Filing date	Apr 29, 2019
Priority date	Jul 31, 2018
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

The disclosure relates to a method and apparatus for converting a grayscale, and a display device, where color coordinates of respective pixel elements are determined according to grayscales corresponding to red sub-pixels, green sub-pixels, and blue sub-pixels in the respective pixel elements in image data of a frame to be displayed, and then the distances between the color coordinates of the respective pixel elements, and color coordinates of a preset white pixel on the panel, in a CIE chroma graph are determined; and the maximum grayscales of white sub-pixels in the respective pixel elements are further determined according to the respective determined distances and a preset segmentation function.

First claim

The invention claimed is:

1. A method for converting a grayscale, the method comprising:
receiving image data of a frame to be displayed, wherein the image data of the frame to be displayed comprise grayscales corresponding respectively to red sub-pixels, green sub-pixels, and blue sub-pixels in respective pixel elements;
determining color coordinates of the respective pixel elements according to the grayscales corresponding to the red sub-pixels, the green sub-pixels, and the blue sub-pixels in the respective pixel elements;
determining distances between the color coordinates of the respective pixel elements and color coordinates of a preset white pixel on a panel, in a CIE chroma graph; and
determining a maximum grayscale of the white sub-pixels in the respective pixel elements according to respective determined distances and a preset segmentation function;
wherein the determining the maximum grayscale of the white sub-pixels in the respective pixel elements according to the respective determined distances and the preset segmentation function comprises:
for each pixel element, determining the maximum grayscale W pixel_max of the white sub-pixel in the pixel element in the equation of:

W

pixel
⁢

⁢
_
⁢

⁢
m
⁢

⁢
ax

=

f
⁡

(
k
)

*

W

ma
⁢

⁢
x

,
and

f
⁡

(
k
)

=

{

α
0

+

α
1

⁢
k

+

α
2

⁢

k
2

+

α
3

⁢

k
2

+
…
+

α
n

⁢

k
n

(

0
≤
k
≤

k
1

)

β
0

+

β
1

⁢
k

+

β
2

⁢

k
2

+

β
3

⁢

k
3

+
…
+

β
m

⁢

k
m

(

k
1

<
k
≤
1

)

,

wherein k represents the distance between the color coordinates of the pixel element, and the color coordinates of the preset white pixel on the panel, in the CIE chroma graph, W max represents a maximum of all normalized grayscales in the image data of the frame to be displayed, α n and β m represents coefficients respectively, n≥0 and n is an integer, m≥0 and m is an integer, and 0≤k 1 ≤1.

2. The method for converting a grayscale according to claim 1 , wherein k 1 =0.5, n=3, and m=2.

3. The method for converting a grayscale according to claim 1 , wherein the determining the color coordinates of the respectiv

Assignees

• Boe Technology Group Co Ltd

Inventors

• Dai Bin
• Xi Yanhui
• Zhang Xiaomang
• Sun Yan
• Li Yue
• Bi Yuxin
• Gao Yankai

Classifications

• G09G3/3607 Primary

  for displaying colours or for displaying grey scales with a specific pixel layout, e.g. using sub-pixels (display of colours in flat matrix panels other than liquid crystal displays G09G3/2003; grey scales specific for television H04N3/127) · CPC title

• G09G3/2003 Primary

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

• G09G2300/0452

  Details of colour pixel setup, e.g. pixel composed of a red, a blue and two green components · CPC title

• G09G3/2007 Primary

  Display of intermediate tones · CPC title

• G09G2340/06

  Colour space transformation · CPC title