BRIGHTNESS CONTROL APPARATUS AND BRIGHTNESS CONTROL METHOD

• US 20120044277A1
• Filed: 08/19/2011
• Published: 02/23/2012
• Est. Priority Date: 08/23/2010
• Status: Abandoned Application

• Current Assignee: ATRC Corporation, Mitsumi Electric Co., Ltd. (Minebea Mitsumi, Inc.)
• Original Assignee: ATRC Corporation, Mitsumi Electric Co., Ltd. (Minebea Mitsumi, Inc.)
• Inventors: ADACHI, Takeshi
• Application Number:
  US13/213,206
• Publication Number:
  US 20120044277A1
• Time in Patent Office: Days
• US Class Current: 345/690
• CPC Class Codes: G09G 2320/064 by time modulation of the brightness of the illumination source
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2360/16 Calculation or use of calculated indices related to luminance levels in display data
• CPC Class Codes: G09G 3/3426 the different display panel areas being distributed in two dimensions, e.g. matrix

Abstract

A brightness control apparatus for performing brightness control on backlights for a display screen based on an input image signal, includes: an image information analysis unit configured to analyze information of at least one item of an average brightness level, brightness histogram information, color histogram information and frequency histogram information that are obtained from an image frame included in the image signal; a block information obtaining unit configured to divide the image frame into blocks and to obtain image information for each of the blocks based on an analysis result of the image information analysis unit; a brightness correction unit configured to perform brightness correction on backlights corresponding to each of the blocks divided by the block information obtaining unit; and a backlight driving control unit configured to perform driving control of the backlights for each of the blocks based on correction information obtained by the brightness correction unit.

Claims

1. A brightness control apparatus for performing brightness control on backlights for a display screen based on an input image signal, comprising:

an image information analysis unit configured to analyze information of at least one item of an average brightness level, brightness histogram information, color histogram information and frequency histogram information that are obtained from an image frame included in the image signal;

a block information obtaining unit configured to divide the image frame into blocks and to obtain image information for each of the blocks based on an analysis result of the image information analysis unit;

a brightness correction unit configured to perform brightness correction on backlights corresponding to each of the blocks divided by the block information obtaining unit; and

a backlight driving control unit configured to perform driving control of the backlights for each of the blocks based on correction information obtained by the brightness correction unit.

2. The brightness control apparatus as claimed in claim 1, wherein the brightness correction unit performs offset correction and/or non-linear correction for a brightness value of the backlights based on the analysis result obtained by the image information analysis unit.

3. The brightness control apparatus as claimed in claim 1, comprising:

an image correction unit configured to perform correction for the image signal based on brightness correction information for the backlights that is obtained by the brightness correction unit.

4. The brightness control apparatus as claimed in claim 1, wherein the image information analysis unit analyzes an area where brightness change in the image frame is equal to or greater than a predetermined value by using at least one of the average brightness level, the brightness histogram information, the color histogram information and the frequency histogram information.

5. A brightness control method for performing brightness control on backlights for a display screen based on an input image signal, comprising:

an image information analysis step of analyzing information of at least one item of an average brightness level, brightness histogram information, color histogram information and frequency histogram information that are obtained from an image frame included in the image signal;

a block information obtaining step of dividing the image frame into blocks and obtaining image information for each of the blocks based on an analysis result of the image information analysis step;

a brightness correction step of performing brightness correction on backlights corresponding to each of the blocks divided by the block information obtaining step; and

a backlight driving control step of performing driving control of the backlights for each of the blocks based on correction information obtained by the brightness correction step.

6. The brightness control method as claimed in claim 5, wherein the brightness correction step includes:

performing offset correction and/or non-linear correction for a brightness value of the backlights based on the analysis result obtained by the image information analysis step.

7. The brightness control method as claimed in claim 5, comprising:

an image correction step of performing correction for the image signal based on brightness correction information for the backlights that is obtained by the brightness correction step.

8. The brightness control method as claimed in claim 5, wherein the image information analysis step includes:

analyzing an area where brightness change in the image frame is equal to or greater than a predetermined value by using at least one of the average brightness level, the brightness histogram information, the color histogram information and the frequency histogram information.