Dynamic net power control for OLED and local dimming LCD displays

Patent metadata

Field	Value
Publication number	US-10297191-B2
Application number	US-201615239743-A
Country	US
Kind code	B2
Filing date	Aug 17, 2016
Priority date	Jan 29, 2016
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A method of power control of a display system, the method including receiving dynamic metadata corresponding to input image data, determining a panel load level of the display system based on the dynamic metadata, and applying a first net power control (NPC) function to the display system during a first scene based on the panel load level.

First claim

What is claimed is:

1. A method of power control of a display system, the method comprising:
receiving first dynamic metadata corresponding to input image data;
determining, at a beginning of a first scene, an expected panel load level of the display system based on the first dynamic metadata, the expected panel load level corresponding to one or more image frames to be subsequently displayed after the beginning of the first scene; and
applying a first net power control (NPC) function to the display system during the first scene based on the expected panel load level,
wherein the first dynamic metadata is received prior to display of the beginning of the first scene, and
wherein the first NPC function is applied during an entirety of the first scene.

2. The method of claim 1 , further comprising:
receiving a second dynamic metadata corresponding to an input image data from a second scene;
determining a panel load level of the display system based on the second dynamic metadata; and
applying a second NPC function to the display system during the second scene based on the panel load level.

3. The method of claim 1 , further comprising:
detecting a detected panel load level of the display system corresponding to a first image frame of the first scene;
setting a NPC panel load basis value of the first NPC function to a first value according to the detected panel load level;
detecting a panel load that exceeds an anticipated NPC function range caused by an increased panel load level at a second image frame of the first scene that is after the first image frame, and that is an out-of-range frame; and
adjusting the NPC panel load basis value of the first NPC function to a second value that is higher than the first value upon the out-of-range frame.

4. The method of claim 3 , further comprising detecting a local peak in a plurality of panel load levels during the first scene, wherein the second value is higher than the local peak.

5. The method of claim 4 , further comprising maintaining the second value as the NPC panel load basis value of the first NPC function until a second scene, or until detecting an additional local peak in another plurality of panel load levels that is higher than the local peak.

6. The method of claim 4 , further comprising:
detecting a low panel load after the local peak; and
readjusting the NPC panel load basis value of the first NPC function after the local peak at a constant decreasing rate.

7. The method of claim 1 , further comprising applying a second NPC function to a second scene occurring after a change in panel load levels, the first NPC function and the second NPC function being different.

8. The method of claim 1 , wherein the first dynamic metadata comprises information corresponding to at least one of:
a duration of one of the first scene;
a peak image brightness of the first scene;
a minimum image brightness the first scene;
an average brightness of an image frame of the first scene;
a maximum frame average luminance level (MaxFALL) of the first scene;
spatial information about image content of the first scene; or
suggested color model information of the first scene.

9. The method of claim 1 , wherein the determining a change of scenes between image frames comprises:
calculating one or more statistics corresponding to each of image frames corresponding to the input image data;
storing the statistics; and
comparing the statistics to determine that a first image frame of the image frames belongs to the first scene, and to determine that a second image frame of the image frames belongs to a second scene.

10. The method of claim 1 , further comprising setting a NPC function such that it minimizes fluctuations in image gain.

11. The method of claim 1 , wherein the first NPC function is further based on a low power mode.

12. The method of claim 1 , wherein the first NPC function is further based on an operating temperature of the display system exceeding a temperature threshold.

13. A display system comprising:
a display panel for displaying images according to input image data;
a processor; and
a memory, wherein the memory has stored thereon instructions that, when executed by the processor, causes the processor to:
detect dynamic metadata corresponding to the input image data;
determine, prior to displaying an initial image frame, an expected panel load level of the display system based on the dynamic metadata, the expected panel load level corresponding to one or more image frames to be subsequently displayed after the initial image frame;
apply a first net power control (NPC) function to the display system during a first scene based on the expected panel load level;
detect an interruption of a sequence of the image frames of the first scene; and
apply a second NPC function to a second scene occurring after the interruption, the first and second NPC functions being different,

wherein the dynamic metadata is received prior to display of a beginning of the first scene, and
wherein the first NPC function is applied during an entirety of the first scene.

14. The display system of claim 13 , wherein the instructions, when executed by the processor, further cause the processor to:
detect a detected panel load level of the display system corresponding to a first image frame of the first scene;
set a NPC panel load basis value of the first NPC function to a first value according to the detected panel load level;
detect an excess in load caused by a change in the input image data at a second image frame of the first scene that is after the first image frame; and
adjust the first NPC function to a second function such that a gain level is lower and thus more sustainable than the first value upon the excess in load.

15. The display system of claim 14 , wherein the instructions, when executed by the processor, further cause the processor to detect an elevated panel load level during the first scene, wherein the second function is higher than the elevated panel load level.

16. The display system of claim 15 , wherein the instructions, when executed by the processor, further cause the processor to maintain the second function as the NPC panel load basis value for determining an appropriate first NPC function until a second scene, or until detecting an additional elevated panel load level that is higher than the elevated panel load level.

17. The display system of claim 15 , wherein the instructions, when executed by the processor, further cause the processor to:
detect a low panel load after the elevated panel load level; and
readjust the NPC panel load basis value of the first NPC function after the elevated panel load level at a measured rate.

18. The display system of claim 13 , wherein the instructions, when executed by the processor, further cause the processor to apply a second NPC function to a second scene occurring after a change in panel load level, the first NPC function and the second NPC function being different.

19. The display system of claim 13 , wherein the dynamic metadata comprises information corresponding to at least one of:
a duration of one of the first scene or of a second scene;
a peak image brightness of one of the first or second scenes;
a minimum image brightness one of the first or second scenes;
an average brightness of an image frame of one of the first or second scenes;
a maximum frame average luminance level (MaxFALL) of one of the first or second scenes;
spatial information about image content of one of the first or

Assignees

• Samsung Display Co Ltd

Inventors

• Hoffman David M

Classifications

• G09G2360/16

  Calculation or use of calculated indices related to luminance levels in display data · CPC title

• G09G3/36 Primary

  using liquid crystals · CPC title

• G09G2330/021

  Power management, e.g. power saving · CPC title

• G09G2320/062

  Adjustment of illumination source parameters · CPC title

• G09G2320/0646

  Modulation of illumination source brightness and image signal correlated to each other · CPC title