Variable refresh rate gamma correction

Patent metadata

Field	Value
Publication number	US-10147370-B2
Application number	US-201615338253-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Oct 29, 2015
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A method, computer program product, and system perform gamma correction for a variable refresh rate display panel. An image is received for display on a screen of a display device. The image is adjusted based on gamma correction factors that are dependent on a variable refresh rate of the display device and the adjusted image is output for display on the screen of the display device.

First claim

What is claimed is:

1. A method, comprising:
receiving an image for display on a screen of a display device;
obtaining a first gamma correction factor and a second gamma correction factor, wherein the first and second gamma correction factors depend on a variable refresh rate and the variable refresh rate is based on a refresh frequency specified for the display device and a varying image rendering time;
interpolating between the first gamma correction factor and the second gamma correction factor based on a refresh rate for a currently displayed image to produce a third gamma correction factor corresponding to the refresh rate;
scaling at least one pixel component of the image by the third gamma correction factor; and
outputting the adjusted image for display on the screen of the display device.

2. The method of claim 1 , further comprising, prior to adjusting the image, writing the first and second gamma correction factors associated with a first refresh rate to a first lookup table.

3. The method of claim 1 , further comprising, prior to adjusting the image, determining the refresh rate for the currently displayed image.

4. The method of claim 3 , wherein determining the refresh rate comprises measuring a frame duration time for the currently displayed image.

5. The method of claim 1 , wherein the first gamma correction factor and the second gamma correction factor are obtained from a look-up-table.

6. The method of claim 1 , wherein the first and second gamma correction factors are also configured to perform overdrive operations.

7. The method of claim 1 , wherein sets of gamma correction factors are stored in look-up tables, each set of gamma correction factors corresponding to a different refresh rate, and the first and second gamma correction factors are read from a first look-up table of the look-up tables corresponding to the refresh rate for the currently displayed image.

8. The method of claim 1 , wherein adjusting the image is performed by circuitry configured to implement a mathematical formula defining a curve to produce the adjusted image based on the refresh rate for the currently displayed image.

9. A system, comprising:
a memory storing an image; and
a processor configured to:
receive the image for display on a screen of a display device;
obtain a first gamma correction factor and a second gamma correction factor, wherein the first and second gamma correction factors depend on a variable refresh rate and the variable refresh rate is based on a refresh frequency specified for the display device and a varying image rendering time;
interpolate between the first gamma correction factor and the second gamma correction factor based on a refresh rate for a currently displayed image to produce a third gamma correction factor corresponding to the refresh rate;
scale at least one pixel component of the image by the third gamma correction factor; and
output the adjusted image for display on the screen of the display device.

10. The system of claim 9 , wherein the processor is further configured to write the first and second gamma correction factors associated with a first refresh rate to a first lookup table.

11. The system of claim 9 , wherein the processor is further configured to determine the refresh rate for the currently displayed image prior to adjusting the image.

12. The system of claim 11 , wherein the refresh rate is determined by measuring a frame duration time for the currently displayed image.

13. The system of claim 9 , wherein the first and second gamma correction factors are also configured to perform overdrive operations.

14. The system of claim 9 , wherein the processor comprises circuitry configured to implement a mathematical formula defining a curve to produce the adjusted image based on the refresh rate for the currently displayed image.

15. A non-transitory, computer-readable storage medium storing instructions that, when executed by a processor, cause the processor to perform steps comprising:
receiving an image for display on a screen of a display device;
obtaining a first gamma correction factor and a second gamma correction factor, wherein the first and second gamma correction factors depend on a variable refresh rate and the variable refresh rate is based on a refresh frequency specified for the display device and a varying image rendering time;
interpolating between the first gamma correction factor and the second gamma correction factor based on a refresh rate for a currently displayed image to produce a third gamma correction factor corresponding to the refresh rate;
scaling at least one pixel component of the image by the third gamma correction factor; and
outputting the adjusted image for display on the screen of the display device.

16. The non-transitory, computer-readable storage medium of claim 15 , further comprising instructions that cause the processor to write the first and second gamma correction factors associated with a first refresh rate to a first lookup table.

17. The non-transitory, computer-readable storage medium of claim 15 , further comprising instructions that cause the processor to determine the refresh rate for the currently displayed image prior to adjusting the image.

18. The non-transitory, computer-readable storage medium of claim 17 , wherein the refresh rate is determined by measuring a frame duration time for the currently displayed image.

19. The non-transitory, computer-readable storage medium of claim 15 , wherein the first and second gamma correction factors are also configured to perform overdrive operations.

20. The non-transitory, computer-readable storage medium of claim 15 , wherein sets of gamma correction factors are stored in look-up tables, each set of gamma correction factors corresponding to a different refresh rate, and the first and second gamma correction factors are read from a first look-up table of the look-up tables corresponding to the refresh rate for the currently displayed image.

Assignees

• Nvidia Corp

Inventors

• Verbeure Tom
• Schutten Robert Jan
• Slavenburg Gerrit A

Classifications

• G09G2320/0276

  for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction · CPC title

• G09G3/3611 Primary

  Control of matrices with row and column drivers · CPC title

• G09G2320/0247

  Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes · CPC title

• G09G2340/0435

  Change or adaptation of the frame rate of the video stream · CPC title

• G09G2320/0252

  Improving the response speed · CPC title