Multi zone backlight controlling method and device thereof

• US 10,650,758 B2
• Filed: 07/09/2018
• Issued: 05/12/2020
• Est. Priority Date: 11/21/2017
• Status: Active Grant

• Current Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Original Assignee: Wuhan China Star Optoelectronics Technology Co., Ltd. (TCL Technology Group Corp.)
• Inventors: Zha, Guowei
• Primary Examiner(s): Boddie, William
• Assistant Examiner(s): Parker, Jeffrey
• Application Number:
  US16/030,472
• Publication Number:
  US 20190156770A1
• Time in Patent Office: 673 Days
• CPC Class Codes: G09G 2320/0233 Improving the luminance or brightness uniformity across the screen
• CPC Class Codes: G09G 2320/103 Detection of image changes, e.g. determination of an index representative of the image change
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/342 using several illumination sources separately controlled corresponding to different display panel areas, e.g. along one dimension such as lines
• CPC Class Codes: G09G 3/3607 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

Abstract

Provided are a multi zone backlight controlling method and a device thereof. The method includes: obtaining original grayscale values of pixels of the image; obtain a backlight control coefficient correction factor according to the original grayscale value; obtaining a first backlight control coefficient and a second backlight control coefficient based on the backlight control coefficient correction factor and the original grayscale values, and adjusting backlight brightness according to the first backlight control coefficient and the second backlight control coefficient, thereby reducing difference between the display image and the real image.

Claims

1. A multi zone backlight controlling method, comprising:

obtaining original grayscale values of pixels of an image displayed in a display area, wherein the display area includes a first partition and a second partition, the image includes a first image block and a second image block, the first image block is displayed in the first partition, and the second image block is displayed in the second partition, the original grayscale value includes a first original grayscale value of each pixel point in the first image block and a second original grayscale value of each pixel point in the second image block;

obtaining a backlight control coefficient correction factor of the image according to the original grayscale value;

obtaining a first backlight control coefficient of the first partition based on the backlight control coefficient correction factor and the first original grayscale value, and adjusting a backlight brightness of the first partition according to the first backlight control coefficient; and

obtaining a second backlight control coefficient of the second partition based on the backlight control coefficient correction factor and the second original grayscale value, and adjusting a backlight brightness of the second partition according to the second backlight control coefficient;

wherein the step of obtaining the backlight control coefficient correction factor of the image according to the original grayscale value comprises;

performing an average operation on the first original grayscale values to obtain a first reference grayscale value of the first image block, and performing an average operation on the second original grayscale values to obtain a second reference grayscale value of the second image block, and performing an average operation on the first reference grayscale value and the second reference grayscale value to obtain a target reference grayscale value of the image, and obtaining the backlight control coefficient correction factor based on the target reference grayscale value;

or, performing an average operation on the original grayscale values of pixels of the image to obtain the target reference grayscale value of the image, and obtaining the backlight control coefficient correction factor based on the target reference grayscale value;

wherein the step of obtaining the backlight control coefficient correction factor based on the target reference grayscale value comprises;

a function mapping relationship between the target reference grayscale value and the backlight control coefficient correction factor;

2. The method according to claim 1, wherein the step of obtaining the first backlight control coefficient of the first partition based on the backlight control coefficient correction factor and the first original grayscale value comprises:

comparing the first original grayscale value with a preset grayscale threshold to obtain a target grayscale value greater than the preset grayscale threshold in the first original grayscale value;

obtaining a weighted average value of the target grayscale values, and obtaining a first reference backlight control coefficient of the first image block according to the weighted average value; and

obtaining the first backlight control coefficient based on the first reference backlight control coefficient and the backlight control coefficient correction factor.

3. The method according to claim 1, wherein the step of obtaining the first backlight control coefficient of the first partition based on the backlight control coefficient correction factor and the first original grayscale value comprises:

comparing the first original grayscale value with a preset grayscale threshold to obtain a target grayscale value greater than the preset grayscale threshold in the first original grayscale value;

determining whether a number of the target grayscale values is greater than a preset number, and as the number of the target grayscale values is greater than the preset number, the target grayscale value is the first reference backlight control coefficient of the first image block; and

obtaining the first backlight control coefficient based on the first reference backlight control coefficient and the backlight control coefficient correction factor.

4. A multi zone backlight controlling device, comprising:

an obtaining unit, obtaining original grayscale values of pixels of an image displayed in a display area, wherein the display area includes a first partition and a second partition, the image includes a first image block and a second image block, the first image block is displayed in the first partition, and the second image block is displayed in the second partition, the original grayscale value includes a first original grayscale value of each pixel point in the first image block and a second original grayscale value of each pixel point in the second image block;

a calculating unit, obtaining a backlight control coefficient correction factor of the image according to the original grayscale value;

a first processing unit, obtaining a first backlight control coefficient of the first partition based on the backlight control coefficient correction factor and the first original grayscale value, and adjusting a backlight brightness of the first partition according to the first backlight control coefficient; and

a second processing unit, obtaining a second backlight control coefficient of the second partition based on the backlight control coefficient correction factor and the second original grayscale value, and adjusting a backlight brightness of the second partition according to the second backlight control coefficient;

wherein the calculating unit comprises;

a first calculating module, performing an average operation on the first original grayscale values to obtain a first reference grayscale value of the first image block, and performing an average operation on the second original grayscale values to obtain a second reference grayscale value of the second image block, and performing an average operation on the first reference grayscale value and the second reference grayscale value to obtain a target reference grayscale value of the image, and obtaining the backlight control coefficient correction factor based on the target reference grayscale value;

a second calculating module, performing an average operation on the original grayscale values of pixels of the image to obtain the target reference grayscale value of the image, and obtaining the backlight control coefficient correction factor based on the target reference grayscale value;

wherein the first calculating module comprises;

a function mapping relationship between the target reference grayscale value and the backlight control coefficient correction factor;

5. The device according to claim 4, wherein the first processing unit comprises:

a first processing module, comparing the first original grayscale value with a preset grayscale threshold to obtain a target grayscale value greater than the preset grayscale threshold in the first original grayscale value;

a third calculating module, obtaining a weighted average value of the target grayscale values, and obtaining a first reference backlight control coefficient of the first image block according to the weighted average value; and

a second processing module, obtaining the first backlight control coefficient based on the first reference backlight control coefficient and the backlight control coefficient correction factor.

6. The device according to claim 4, wherein the first processing unit comprises:

a third processing module, comparing the first original grayscale value with a preset grayscale threshold to obtain a target grayscale value greater than the preset grayscale threshold in the first original grayscale value;

a fourth calculating module, determining whether a number of the target grayscale values is greater than a preset number, and as the number of the target grayscale values is greater than the preset number, the target grayscale value is the first reference backlight control coefficient of the first image block; and

a fourth processing module, obtaining the first backlight control coefficient based on the first reference backlight control coefficient and the backlight control coefficient correction factor.