IMAGE COMPENSATION APPARATUS AND METHOD

• US 20080122833A1
• Filed: 06/29/2007
• Published: 05/29/2008
• Est. Priority Date: 07/04/2006
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: CHOE, Won-hee
• Granted Patent: US 8,040,342 B2
• Time in Patent Office: Days
• US Class Current: 345/214
• CPC Class Codes: G06T 5/40 using histogram techniques
• CPC Class Codes: G06T 5/92 based on global image properties
• 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 2320/0606 Manual adjustment
• CPC Class Codes: G09G 2320/0646 Modulation of illumination source brightness and image signal correlated to each other
• CPC Class Codes: G09G 2320/0673 for control of gamma adjustment, e.g. selecting another gamma curve
• CPC Class Codes: G09G 2330/021 Power management, e.g. power saving
• CPC Class Codes: G09G 2360/144 the light being ambient light
• CPC Class Codes: G09G 3/3406 Control of illumination source illumination devices structurally associated with liquid crystal cells G02F1/1336
• CPC Class Codes: H04N 5/20 Circuitry for controlling amplitude response

Abstract

An image compensation apparatus and method is provided. The image compensation apparatus includes a power control module which controls a light emitting unit according to a power control input signal input thereto by a user and provides power reduction information corresponding to the power control input signal, a control parameter generation module which determines a threshold based on the power reduction information, an image compensation module which divides input image information according to the threshold and converts the input image information according to image control information, and an output module which outputs image information obtained by the conversion performed by the image compensation module.

Claims

1. An image compensation apparatus comprising:

a power control module which controls a light emitting unit according to a power control input signal input thereto by a user and provides power reduction information corresponding to the power control input signal;

a control parameter generation module which determines a threshold based on the power reduction information;

an image compensation module which divides input image information according to the threshold and converts the input image information according to image control information; and

an output module which outputs image information obtained by the conversion performed by the image compensation module.

2. The image compensation apparatus of claim 1, wherein the image control information increases the input image information by a predetermined amount.

3. The image compensation apparatus of claim 1, wherein the image compensation module does not convert the input image information less than the threshold.

4. The image compensation apparatus of claim 1, wherein the image compensation module converts the input image information by increasing the input image information less than the threshold by a predetermined amount.

11. The image compensation method of claim 1, wherein the dividing of the input image information comprises:

dividing an original image into a first image information section and a second image information section according to the threshold;

maintaining image information belonging to the first image information section; and

converting image information belonging to the second image information section according to the image control information.

12. The image compensation method of claim 11, wherein the image control information increases the input image information by a predetermined amount.

5. The image compensation apparatus of claim , wherein the image compensation module divides an original image into a first image information section and a second image information section according to the threshold, maintains image information belonging to the first image information section, and converts image information belonging to the second image information section according to the image control information.

6. The image compensation apparatus of claim 5, wherein the image control information increases the input image information by a predetermined amount.

7. An image compensation method comprising:

controlling a light emitting unit according to a power control input signal input thereto by a user and providing power reduction information corresponding to the power control input signal;

determining a threshold based on the power reduction information;

dividing input image information according to the threshold and converting the input image information according to image control information; and

outputting image information obtained by the conversion performed in on the input image information.

8. The image compensation method of claim 7, wherein the image control information increases the input image information by a predetermined amount.

9. The image compensation method of claim 7, wherein the dividing of the input image information comprises not compensating for the input image information less than the threshold.

10. The image compensation method of claim 7, wherein the dividing of the input image information comprises converting the input image information by increasing the input image information less than the threshold by a predetermined amount.

13. A method of compensating an image on a display, comprising:

receiving a control signal to reduce power to the display;

determining at least one threshold in pixel information of the image according to the received control signal to reduce power;

determining at least one image compensating function that selectively adjusts the pixel information;

compensating the image by applying the image compensating function to the pixel information; and

outputting the compensated image to the display.

14. The method of claim 13, wherein the determining of the at least one threshold includes referencing a lookup table containing a predetermined relationship between the threshold and a reduce power information.

15. The method of claim 13, wherein the threshold divides the pixel information into at least a first section and a second section.

16. The method of claim 15, wherein the compensating of the image includes applying the image compensation function only to the first section and not the second section.

17. The method of claim 15, wherein the pixel information is adjusted for only the first section and not the second section.

18. A method of adjusting an image on a display based on changing an amount of emitted light, comprising:

changing an amount of power supplied to and/or consumed by the display to change the amount of emitted light;

adjusting a portion of the pixel information of the image while maintaining a remaining portion of the pixel information of the image to improve both brightness and contrast of the image simultaneously.

19. The method of claim 18, wherein the adjusted portion of the pixel information and the maintained portion of the pixel information are defined by a threshold.

20. The method of claim 19, wherein the threshold is determined according to the amount of the change in the power of the display.

21. The method of claim 18, wherein the maintained portion of the pixel information is proportional to a reduction of the power of the display.

22. The method of claim 18, wherein the maintaining of the remaining portion of the pixel information includes obtaining the remaining portion by referring to a predetermined lookup table.

23. An image compensation apparatus for use with a light emitting unit, comprising:

a power control module to supply power to the light emitting unit;

a control parameter generation module to generate one or more parameters to compensate pixel information of an image based on the supply of power by the power supply module;

an image compensation module to compensate the image by dividing pixel information of the original image; and

an output module to output the compensated image.

24. The image compensating apparatus of claim 23, wherein pixel information of the original image are divided into at least two sections.

25. The image compensating apparatus of claim 24, wherein the pixel information of only one of the two sections are adjusted.

26. The image compensating apparatus of claim 23, wherein the pixel information divided at a threshold, which is determined according to the amount of the change in the supplied power to the light emitting unit.

27. The image compensating apparatus of claim 25, wherein the non-adjusted portion of the pixel information is proportional to the amount of the change in the supplied power to the light emitting unit.

28. The image compensating apparatus of claim 23, wherein the control parameter generation module contains a predetermined lookup table and the division of the pixel information is determined by referring to the predetermined lookup table.

29. The image compensating apparatus of claim 23, wherein the division of the pixel information is determined according to a pattern of distribution of the pixel information of the image.

30. The image compensating apparatus of claim 25, wherein the non-adjusted portion of the pixel information decreases as the supply of power is decreased.

31. An image compensation apparatus to adjust brightness and contrast of a displayed image based on amount of emitted light dependent on a power usage, comprising:

a power detector to detect the power usage; and

a compensator to adjust pixel information of a portion of the image based on the detected power usage and to maintain pixel information of a remaining portion of the image.

32. The image compensation apparatus of claim 31, wherein the maintained portion of the pixel information is based on the amount of the emitted light.

33. The image compensation apparatus of claim 31, wherein an amount of adjustment of the pixel information in the adjusted portion is based on the amount of the emitted light.

34. A computer readable medium recorded with a program for a computer to execute a method of compensating an image on a display, wherein the computer executes the method comprising:

receiving a control signal to reduce power to the display;

determining at least one threshold in pixel information of the image according to the received control signal to reduce power;

determining at least one image compensating function that selectively adjusts the pixel information;

compensating the image by applying the image compensating function to the pixel information; and

outputting the compensated image to the display.

35. The medium of claim 34, wherein the determining of the at least one threshold includes referencing a lookup table containing a predetermined relationship between the threshold and a reduce power information.

36. The medium of claim 34, wherein the threshold divides the pixel information into at least a first section and a second section.

37. The medium of claim 36, wherein the compensating of the image includes applying the image compensating function only to the first section and not the second section.

38. A computer readable medium recorded with a program for a computer to execute a method of adjusting an image on a display based on changing an amount of emitted light, wherein the computer executes the method comprising:

changing an amount of power supplied to and/or consumed by the display to change the amount of emitted light; and

adjusting a portion of the pixel information of the image while maintaining a remaining portion of the pixel information of the image to improve both brightness and contrast of the image simultaneously.

39. The medium of claim 38, wherein the adjusted portion of the pixel information and the maintained portion of the pixel information are defined by a threshold.

40. An image compensation method to enhance both brightness and contrast of an image, comprising:

reducing a supplied and/or consumed power a backlight unit;

maintaining low-luminance grayscale values and increasing medium—

and high-luminance grayscale values of the original image to compensate a reduction in the brightness of the backlight unit corresponding to the reduction in the power.

41. The method of claim 40, wherein the reducing of the supplied and/or consumed power is performed selectively by a user, and/or is based on detection of external ambient light.

42. The method of claim 40, wherein the low-luminance grayscale values and the medium—

and high-luminance grayscale values are delineated by a threshold.

43. The method of claim 42, wherein an amount of the low-luminance grayscale values corresponds to a length L of the threshold, and the compensation of the medium—

and high-luminance grayscale values correspond to a difference D that is increased proportionally according to the reduction in the brightness of the backlight unit.

44. The method of claim 43, wherein the length L and the difference D are adjusted according to a pattern of distribution of the low-luminance grayscale values relative to the medium—

and high-luminance grayscale values.

45. An image compensation method to enhance both brightness and contrast of an image, comprising compensating pixel information of the original image by using a luminance of the original image, wherein if the luminance of the original image is lower than a predefined threshold, pixel information of the original image is not adjusted, but if the luminance of the original image is higher than the predefined threshold, the pixel information of the original image is adjusted by increasing the luminance of the original image by a predetermined compensation amount.

46. The image compensation method of claim 45, further comprising if the luminance of the original image is higher than another predefined threshold higher than the predefined threshold, the pixel information of the original image is not adjusted.

47. The image compensation method of claim 45, wherein the predetermined threshold and the predetermined compensation amount are adjusted according to a reduction in brightness of a light emitting unit.

48. The image compensation method of claim 45, wherein the predetermined threshold and the predetermined compensation amount are adjusted according to the pattern of distribution of pixel information of the original image.

49. The image compensation method of claim 45, wherein the predefined threshold is determined based on a lookup table having values of a plurality of thresholds that correspond to luminance reduction amounts.

50. The image compensation method of claim 45, wherein the predetermined compensation amount is determined according to the luminance of the original image.

51. The image compensation method of claim 45, wherein the predetermined compensation amount is determined with reference to a lookup table containing pixel information that correspond to compensation amounts.

52. The image compensation method of claim 45, wherein the predefined threshold is determined from the intersection between the value pixel information x that satisfies the following equation:

x=(ax⁵+bx⁴+cx³+dx²+ex¹+f)*g,

where a, b, c, d, e, and f are coefficients corresponding to a reduction in brightness of a light emitting unit, and g is the predetermined compensation amount.

53. The image compensation method of claim 45, wherein the method reduces the power consumption of a display device by compensating the pixel information of the original image so that deterioration of the quality of the original image is reduced even when the luminance of the original image is reduced.

54. A method of compensating an image on a display, comprising:

dividing pixel information of the image into two or more sections based on power supplied to and/or consumed by the display; and

adjusting the pixel information of one or more of the sections.

55. The method of claim 54, wherein the pixel information of at least one of the sections are not adjusted.

56. The method of claim 54, wherein the adjusting of the pixel information is based on the supplied and/or consumed power.

57. The method of claim 54, wherein the dividing and/or the adjusting of the pixel information is based on a change of the supplied and/or consumed power.

58. The method of claim 57, wherein the change is a reduction.

59. A method of compensating an image on a display, comprising:

dividing pixel information of the image into two or more sections based on power supplied to and/or consumed by the display; and

adjusting the pixel information of one or more of the sections differently from the pixel information of a remainder of the sections.

60. The method of claim 59, wherein the pixel information of at least one of the sections are not adjusted.

61. An image compensation apparatus for use with a display, comprising:

pixel information of an image displayed on the display being divided into two or more sections based on power supplied to and/or consumed by the display; and

the pixel information of one or more of the sections being adjusted differently from the pixel information of a remainder of the sections.

62. The image compensation apparatus of claim 61, wherein the pixel information of at least one of the sections are not adjusted.

63. The image compensation apparatus of claim 61, wherein the power supplied to and/or consumed by the display is reduced.

64. A method of processing an image via an image device, comprising:

converting a first power level of the image device to a second power level of the image device;

dividing image information of the image into at least two groups, and separately processing the image information so that a picture quality of the image that is output at the second power level is the same as that of the image that is output at the first power level; and

outputting the image information processed according to each of the groups at the second power level.

65. The method of claim 64, further comprising setting a threshold according to the second power level in order to divide the image information into the at least two groups.

66. The method of claim 65, wherein the dividing of the image information into the at least two groups includes:

processing the image information in order to maintain an image information value if the image information value is smaller than the threshold; and

processing the image information in order to increase the image information value if the image information value is equal to or greater than the threshold.

67. The method of claim 65, wherein the dividing of the input image information into the at least two groups includes:

processing the image information so that an image information value is increased by a first increase rate if the image information value is smaller than the threshold; and

processing the image information so that the image information value is increased by a second increase rate if the image information value is equal to or greater than the threshold.

68. The method of claim 64, wherein the image information is a luminance information of pixels.