Display control apparatus and display control method

• US 10,504,456 B2
• Filed: 07/15/2016
• Issued: 12/10/2019
• Est. Priority Date: 07/30/2015
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Inokawa, Hiroyuki
• Primary Examiner(s): Haley, Joseph R
• Application Number:
  US15/578,297
• Publication Number:
  US 20180144690A1
• Time in Patent Office: 1,243 Days
• Field of Search: None
• CPC Class Codes: G09G 2320/0271 Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
• CPC Class Codes: G09G 2330/045 Protection against panel overheating
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/32 semiconductive, e.g. using light-emitting diodes [LED]
• CPC Class Codes: G09G 3/3225 using an active matrix
• 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: H04N 5/57 Control of contrast or brightness

Abstract

The present disclosure relates to a display control apparatus that enables a rise in surface temperature of a display apparatus to be suppressed by lowering a gain value of a high-luminance area, and a display control method.

A display control apparatus according to an aspect of the present disclosure includes: a high-luminance area detection unit that sets a measurement area on a screen of the video signal, calculates an APL value of the set measurement area, and detects a high-luminance area on the basis of a result of a comparison between the calculated APL value and a threshold value; a control unit that causes a LUT, in which an APL value of each pixel is an input and a gain value is an output, to be generated on the basis of the APL value of the detected high-luminance area; an APL value calculation unit that calculates the APL value of each pixel on the basis of pixel values of the video signal; a LUT unit that generates the LUT under control of the control unit and references the generated LUT to output the gain value corresponding to the calculated APL value of each pixel; and a multiplication unit that multiplies the pixel values of the video signal by the output gain value. The present disclosure is applicable to a video monitor.

Claims

1. A display control apparatus, comprising:

processing circuitry configured to

set a measurement area of an image of a video signal,

calculate an average picture level (APL) value of the set measurement area, and

detect a high-luminance area on the basis of a result of a comparison between the calculated APL value and a threshold value at which a temperature of the set measurement area on a reference display is determined to exceed a predetermined temperature.

2. The display control apparatus according to claim 1, wherein

the threshold value is set on the basis of an actual measurement where temperatures of set measurement areas on the reference display with different sizes are measured corresponding to each of a series of possible APL values applied to the set measurement areas.

3. The display control apparatus according to claim 1, wherein the processing circuitry is further configured to:

set multiple measurement areas of the image of the video signal,

calculate multiple APL values of the multiple set measurement areas, and

detect the high-luminance area on the basis of a result of a comparison between a maximum value of the calculated multiple APL values and the threshold value.

4. The display control apparatus according to claim 1, wherein the processing circuitry is further configured to:

set measurement areas of different sizes of the image of the video signal,

calculate APL values of each of the set measurement areas, and

detect the high-luminance area on the basis of the result of a comparison between the calculated APL values and the threshold value.

5. The display control apparatus according to claim 1, wherein the processing circuitry is further configured to:

determine a gain value with which the APL value of the detected high-luminance area can be lowered to a predetermined value, and

notify a look up table (LUT) circuit of the determined gain value.

6. The display control apparatus according to claim 5, wherein

the predetermined value is set on the basis of an actual measurement.

7. The display control apparatus according to claim 1, wherein the processing circuitry is further configured to:

in response to high-luminance areas of the same size being consecutively detected at the same position on the image, generate a nonlinear LUT, in which an APL value of each pixel is an input and a gain value is an output, on the basis of the APL value of the detected high-luminance area that is one of the high-luminance areas.

8. The display control apparatus according to claim 7, wherein the processing circuitry is further configured to:

when no high-luminance areas of the same size at the same position on the image are detected during an interval, generate a linear LUT, in which an APL value of each pixel is an input and a gain value is an output.

9. The display control apparatus according to claim 1, wherein the processing circuitry is further configured to:

indicate that a local luminance correction is being carried out at a position of the measurement area of the image.

10. The display control apparatus of claim 1, wherein the processing circuitry is further configured to:

generate a LUT, in which an APL value of each pixel is an input and a gain value is an output, on the basis of the APL value of the detected high-luminance area;

calculate the APL value of each pixel on the basis of pixel values of the video signal;

output the gain value corresponding to the calculated APL value of each pixel based on the generated LUT; and

multiply the pixel values of the video signal by the output gain value.

11. The display control apparatus according to claim 1, further comprising

a light-emitting display panel to which the multiplied pixel values of the video signal are displayed.

12. A display control method, comprising:

setting a measurement area of an image of a video signal,

calculating an average picture level (APL) value of the set measurement area; and

detecting, by processing circuitry of a display control apparatus, a high-luminance area on the basis of a result of a comparison between the calculated APL value and a threshold value at which a temperature of the set measurement area on a reference display is determined to exceed a predetermined temperature.

13. The method of claim 12, further comprising:

generating a look up table (LUT), in which an APL value of each pixel is an input and a gain value is an output, on the basis of the APL value of the detected high-luminance area;

calculating the APL value of each pixel on the basis of pixel values of the video signal;

output the gain value corresponding to the calculated APL value of each pixel based on the generated LUT; and

multiplying the pixel values of the video signal by the output gain value.

14. The display control method according to claim 12, wherein the threshold value is set on the basis of an actual measurement where temperatures of set measurement areas on the reference display with different sizes are measured corresponding to each of a series of possible APL values applied to the set measurement areas.

15. The display control method according to claim 12, further comprising:

setting multiple measurement areas of the image of the video signal;

calculating multiple APL values of the multiple set measurement areas; and

detecting the high-luminance area on the basis of a result of a comparison between a maximum value of the calculated multiple APL values and the threshold value.

16. The display control method according to claim 12, further comprising:

setting measurement areas of different sizes of the image of the video signal;

calculating APL values of each of the set measurement areas; and

detecting the high-luminance area on the basis of the result of a comparison between the calculated APL values and the threshold value.

17. The display control method according to claim 12, further comprising:

determining a gain value with which the APL value of the detected high-luminance area can be lowered to a predetermined value, and notifying a LUT circuit of the determined gain value.

18. The display control method according to claim 12, wherein the predetermined value is set on the basis of an actual measurement.

19. The display control method according to claim 12, further comprising:

in response to high-luminance areas of the same size being consecutively detected at the same position on the image, generating a nonlinear LUT, in which an APL value of each pixel is an input and a gain value is an output, on the basis of the APL value of the detected high-luminance area that is one of the high-luminance areas.

20. The display control method according to claim 19, further comprising:

when no consecutive high-luminance areas of the same size at the same position on the image are detected during an interval, generating a linear LUT, in which an APL value of each pixel is an input and a gain value is an output.