Parallel pipelines for computing backlight illumination fields in high dynamic range display devices

• US 10,607,552 B2
• Filed: 10/04/2018
• Issued: 03/31/2020
• Est. Priority Date: 02/27/2018
• Status: Active Grant

• Current Assignee: NVIDIA Corporation
• Original Assignee: NVIDIA Corporation
• Inventors: Roever, Jens
• Primary Examiner(s): Cheng, Joe H
• Application Number:
  US16/152,358
• Publication Number:
  US 20190266954A1
• Time in Patent Office: 544 Days
• CPC Class Codes: G09G 2320/0252 Improving the response speed
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2360/141 the light conveying information used for selecting or modulating the light emitting or modulating element
• CPC Class Codes: G09G 2360/145 the light originating from the display screen
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/2096 Details of the interface to the display terminal specific for a flat panel suitable for both CRT and flat panel G09G5/006; specific for a CRT G09G1/167
• 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 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix
• CPC Class Codes: G09G 3/36 using liquid crystals

Abstract

A display controller generates a backlight illumination field (BLIF) based on a coarse point-spread function (PSF) and a correction PSF. The display controller samples the coarse PSF to accumulate light contributions from a larger neighborhood of LEDs around a given LCD pixel. The display controller samples the correction PSF to generate correction factors for a smaller neighborhood of LEDs around the given LCD pixel. The display controller interpolates samples drawn from the coarse PSF and samples drawn from the correction PSF and then combines the interpolated samples to generate a full resolution BLIF.

Claims

1. A computer-implemented method for displaying an image, the method comprising:

generating a first sample associated with a first light source based on a first dataset, wherein the first dataset includes a first plurality of luminance values indexed by a first set of distances;

generating a second sample associated with the first light source based on a second dataset, wherein the second dataset includes a second plurality of luminance values indexed by a second set of distances;

combining the first sample with the second sample to determine a first luminance value associated with light that is contributed to a first screen pixel by the first light source; and

configuring the first screen pixel to output light associated with a first portion of the image based on the first luminance value.

2. The computer-implemented method of claim 1, further comprising determining a first distance between the first light source and the first screen pixel based on geometry data associated with a display screen that includes the first light source and the first screen pixel.

3. The computer-implemented method of claim 2, wherein generating the first sample comprises extracting a first subset of luminance samples from the first dataset based on the first distance, and wherein generating the second sample comprises extracting a second subset of luminance samples from the second dataset based on the first distance.

4. The computer-implemented method of claim 3, wherein generating the first sample further comprises scaling the first subset of luminance samples based on a brightness setting associated with the first light source, and wherein generating the second sample further comprises scaling the second subset of luminance samples based on a brightness setting associated with the first light source.

5. The computer-implemented method of claim 3, wherein generating the first sample further comprises interpolating between at least two samples included in the first subset of luminance samples to generate a first interpolated sample, and wherein generating the second sample further comprises interpolating between at least two samples included in the second subset of luminance samples to generate a second interpolated sample.

6. The computer-implemented method of claim 1, wherein combining the first sample with the second sample comprises adding a first interpolated sample to a second interpolated sample to generate the first luminance value.

7. The computer-implemented method of claim 1, wherein the first dataset defines a coarse approximation of a point-spread function associated with the first light source, and wherein the second dataset defines a set of correction factors for refining the coarse approximation of the point-spread function.

8. The computer-implemented method of claim 1, wherein the first sample and the second sample are generated at least partially in parallel with one another.

9. The computer-implemented method of claim 1, wherein the first dataset includes M samples, the second dataset includes N samples, N and M are integer values, and N is greater than M.

10. The computer-implemented method of claim 1, further comprising:

determining that the first light source resides outside of a boundary that surrounds a second screen pixel;

determining a first distance between the first light source and the second screen pixel;

generating a third sample associated with the first light source based on the first dataset;

determining a second luminance value associated with light that is contributed to the second screen pixel by the first light source based on the third sample; and

configuring the second screen pixel to output light associated with a second portion of the image based on the second luminance value.

11. A display device, comprising:

a display screen; and

a display controller that causes the display screen to display an image by performing the steps of;

generating a first sample associated with a first light source based on a first dataset, wherein the first dataset includes a first plurality of luminance values indexed by a first set of distances,

generating a second sample associated with the first light source based on a second dataset, wherein the second dataset includes a second plurality of luminance values indexed by a second set of distances,

combining the first sample with the second sample to determine a first luminance value associated with light that is contributed to a first screen pixel by the first light source, and

configuring the first screen pixel to output light associated with a first portion of the image based on the first luminance value.

12. The display device of claim 11, wherein the display controller performs the additional step of determining a first distance between the first light source and the first screen pixel based on geometry data associated with the display screen, wherein the display screen includes the first light source and the first screen pixel.

13. The display device of claim 12, wherein the display controller performs the step of generating the first sample by extracting a first subset of luminance samples from the first dataset based on the first distance, wherein the display controller performs the step of generating the second sample by extracting a second subset of luminance samples from the second dataset based on the first distance, and wherein the first subset of luminance samples and the second subset of luminance samples are extracted at least partially in parallel with one another.

14. The display device of claim 13, wherein the display controller further performs the step of generating the first sample by scaling the first subset of luminance samples based on a brightness setting associated with the first light source, wherein the display controller further performs the step of generating the second sample by scaling the second subset of luminance samples based on a brightness setting associated with the first light source, and wherein the first sample and the second sample are generated at least partially in parallel with one another.

15. The display device of claim 13, wherein the display controller further performs the step of generating the first sample by interpolating between at least two samples included in the first subset of luminance samples to generate a first interpolated sample, wherein the display controller further performs the step of generating the second sample by interpolating between at least two samples included in the second subset of luminance samples to generate a second interpolated sample, and wherein the first interpolated sample and the second interpolated sample are generated at least partially in parallel with one another.

16. The display device of claim 11, wherein the display controller performs the step of combining the first sample with the second sample by adding a first interpolated sample to a second interpolated sample to generate the first luminance value.

17. The display device of claim 11, wherein the first data set defines a coarse approximation of a point-spread function associated with the first light source and includes M samples, wherein the second data set defines a set of correction factors for refining the coarse approximation of the point-spread function and includes N samples, and wherein M and N comprise different integer values.

18. The display device of claim 11, wherein the display controller performs the additional steps of:

determining that the first light source resides outside of a boundary that surrounds a second screen pixel;

determining a first distance between the first light source and the second screen pixel;

generating a third sample associated with the first light source based on the first dataset;

determining a second luminance value associated with light that is contributed to the second screen pixel by the first light source based on the third sample; and

configuring the second screen pixel to output light associated with a second portion of the image based on the second luminance value.

19. The display device of claim 11, wherein the display controller performs the additional steps of:

generating a third sample associated with a simulated version of the first light source based on the first dataset;

generating a fourth sample associated with the simulated version of the first light source based on the second dataset;

combining the third sample with the fourth sample to determine a second luminance value associated with light that is reflected to the first screen pixel by an edge of the display screen and derived from the first light source; and

configuring the first screen pixel to output light associated with the first portion of the image based further on the second luminance value.

20. A subsystem for displaying an image, the subsystem comprising:

a first sample pipeline that generates a first sample associated with a first light source based on a first dataset, wherein the first dataset includes a first plurality of luminance values indexed by a first set of distances;

a second sample pipeline that operates in parallel with the first sample pipeline to generate a second sample associated with the first light source based on a second dataset, wherein the second dataset includes a second plurality of luminance values indexed by a second set of distances;

a combiner that is coupled to the first sample pipeline and to the second sample pipeline and that combines the first sample with the second sample to determine a first luminance value associated with light that is contributed to a first screen pixel by the first light source,

wherein the first screen pixel outputs light associated with a first portion of the image based on the first luminance value.