Image processing method and apparatus, storage medium and program

• US 6,814,420 B2
• Filed: 09/26/2002
• Issued: 11/09/2004
• Est. Priority Date: 10/01/2001
• Status: Expired due to Fees

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Iguchi, Ryosuke, Yamazoe, Manabu, Fujita, Takashi, Akiyama, Yuji
• Primary Examiner(s): NGUYEN, THINH H
• Application Number:
  US10/254,517
• Publication Number:
  US 20030063145A1
• Time in Patent Office: 775 Days
• Field of Search: 347/19, 347/43, 347/15, 358/1.9, 358/1.1
• US Class Current: 347/15
• CPC Class Codes: H04N 1/6005 with luminance or chrominance signals, e.g. LC1C2, HSL or YUV
• CPC Class Codes: H04N 1/6027 Correction or control of colour gradation or colour contrast H04N1/6058 takes precedence
• CPC Class Codes: H04N 1/6075 Corrections to the hue

Abstract

Main actual color is reproduced unsatisfactory in some cases according to prior art. An image processing method is provided in which the component values of hue, saturation and lightness of an image represented by image data are independently changed. The hue change amount is made different at each hue angle, the saturation change amount is made different for each hue angle and each saturation value, and the lightness change amount is made different at each hue angle.

Claims

1. An image processing method of changing independently component values of hue, saturation and lightness of an image represented by image data, wherein a change amount of the hue is made different at each hue angle and a change amount of the saturation is made different at each hue angle and each saturation value, and wherein a saturation value is partitioned into a plurality of sections for each hue angle in each divided hue angle group, and a target saturation value is set to each saturation value to change the saturation value.

2. An image processing method according to claim 1, wherein a change amount of the lightness is further made different at each hue angle.

3. An image processing method according to claim 1, wherein the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

4. An image processing method according to claim 1, wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

5. An image processing method comprising:

a first hue conversion step, of shifting a first hue of image data by a first hue angle;

a second hue conversion step, of shifting a second hue of the image data different from the first hue by a second hue angle different from the first hue angle;

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion; and

a shifting step, of shifting the hues having the hue angles between hue angles of the hues before and after conversion in said first hue conversion step to at least the hue after the conversion.

6. An image processing method according to claim 5, wherein conversion characteristics for saturation determined by the hue angle obtained after said first and second hue conversion steps are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

7. An image processing method according to claim 5, wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

8. An image processing method according to claim 5, wherein hue shift and conversion characteristics at said first and second hue conversion steps are determined by setting of a printer driver.

9. An image processing apparatus for changing independently component values of hue, saturation and lightness of an image represented by image data, comprising:

first conversion means for performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

second conversion means for performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a saturation value is partitioned into a plurality of sections for each hue angle in each divided hue angle group, and a target saturation value is set to each saturation value to change the saturation value.

10. An image processing apparatus according to claim 9, wherein a change amount of the lightness is further made different at each hue angle.

11. An image processing apparatus according to claim 9, wherein the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

12. An image processing apparatus according to claim 9, wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

13. An image processing apparatus comprising:

first hue conversion means for shifting image data having a first hue by a first hue angle;

second hue conversion means for shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle;

conversion means for converting at least lightness or saturation of the image data converted by said first and second hue conversion means in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion; and

shifting means for shifting the hues having the hue angles between hue angles of the hues before and after conversion by said first hue conversion means to at least the hue after the conversion.

14. An image processing apparatus according to claim 13, wherein conversion characteristics for saturation determined by the hue angle obtained after conversion by said first and second hue conversion means are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

15. An image processing apparatus according to claim 13, wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

16. An image processing apparatus according to claim 13, wherein hue shift and conversion characteristics to be used by said first and second hue conversion means are determined by setting of a printer driver.

17. A storage medium storing a program for changing independently component values of hue, saturation and lightness of an image represented by image data, the program comprising:

a first conversion step, of performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

a second conversion step, of performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a saturation value is partitioned into a plurality of sections for each hue angle in each divided hue angle group, and a target saturation value is set to each saturation value to change the saturation value.

18. A storage medium according to claim 17, wherein in the program a change amount of the lightness is further made different at each hue angle.

19. A storage medium according to claim 17, wherein in the program the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

20. A storage medium according to claim 17, wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

21. A storage medium storing a program which comprises:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle;

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion; and

a shifting step, of shifting the hues having the hue angles between hue angles of the hues before and after conversion in said first hue conversion steps to at least the hue after the conversion.

22. A storage medium according to claim 21, wherein conversion characteristics for saturation determined by the hue angle obtained by said first and second hue conversion means are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

23. A storage medium according to claim 21, wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

24. A storage medium according to claim 21, wherein hue shift and conversion characteristics to be used by said first and second hue conversion steps are determined by setting of a printer driver.

25. A program for changing independently component values of hue, saturation and lightness of an image represented by image data, the program comprising:

a first conversion step, of performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

a second conversion step, of performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a saturation value is partitioned into a plurality of sections for each hue angle in each divided hue angle group, and a target saturation value is set to each saturation value to change the saturation value.

26. A program comprising:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle;

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion; and

a shifting step, of shifting the hues having the hue angles between hue angles of the hues before and after conversion in said first hue conversion steps to at least the hue after the conversion.

27. An image processing method of changing independently component values of hue, saturation and lightness of an image represented by image data, wherein a change amount of the hue is made different at each hue angle and a change amount of the saturation is made different at each hue angle and each saturation value, and wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

28. An image processing method according to claim 27, wherein a change amount of the lightness is further made different at each hue angle.

29. An image processing method according to claim 27, wherein the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

30. An image processing apparatus for changing independently component values of hue, saturation and lightness of an image represented by image data, comprising:

first conversion means for performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

second conversion means for performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

31. An image processing apparatus according to claim 30, wherein a change amount of the lightness is further made different at each hue angle.

32. An image processing apparatus according to claim 30, wherein the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

33. A storage medium storing a program for changing independently component values of hue, saturation and lightness of an image represented by image data, the program comprising:

a first conversion step, of performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

a second conversion step, of performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

34. A storage medium according to claim 33, wherein in the program a change amount of the lightness is further made different at each hue angle.

35. A storage medium according to claim 33, wherein in the program the hue angle is divided into a plurality of hue angle groups, and a target hue value is set to each hue value in each divided hue angle group to change the hue value.

36. A program for changing independently component values of hue, saturation and lightness of an image represented by image data, the program comprising:

a first conversion step, of performing conversion in such a manner that a change amount of the hue is made different at each hue angle; and

a second conversion step, of performing conversion in such a manner that a change amount of the saturation is made different at each hue angle and each saturation value,

wherein a color table is formed based upon a result of changing the hue and saturation values in a predetermined color space.

37. An image processing method comprising:

a first hue conversion step, of shifting a first hue of image data by a first hue angle;

a second hue conversion step, of shifting a second hue of the image data different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein conversion characteristics for saturation determined by the hue angle obtained after said first and second hue conversion steps are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

38. An image processing apparatus comprising:

first hue conversion means for shifting image data having a first hue by a first hue angle;

second hue conversion means for shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

conversion means for converting at least lightness or saturation of the image data converted by said first and second hue conversion means in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein conversion characteristics for saturation determined by the hue angle obtained by said first and second hue conversion means are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

39. A storage medium storing a program which comprises:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein conversion characteristics for saturation determined by the hue angle obtained in said first and second hue conversion steps are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

40. A program comprising:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted at said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein conversion characteristics for saturation determined by the hue angle obtained in said first and second hue conversion steps are prepared for each predetermined hue angle, and conversion characteristics for saturation at a hue angle different from the predetermined hue angle are determined through interpolation between a plurality of prepared conversion characteristics.

41. An image processing method comprising:

a first hue conversion step, of shifting a first hue of image data by a first hue angle;

a second hue conversion step, of shifting a second hue of the image data different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

42. An image processing apparatus comprising:

first hue conversion means for shifting image data having a first hue by a first hue angle;

second hue conversion means for shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

conversion means for converting at least lightness or saturation of the image data converted by said first and second hue conversion means in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

43. A storage medium storing a program which comprises:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

44. A program comprising:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein the image data after the hue conversion is converted into image data in excess of a monitor color reproduction range by using the conversion characteristics for saturation.

45. An image processing method comprising:

a first hue conversion step, of shifting a first hue of image data by a first hue angle;

a second hue conversion step, of shifting a second hue of the image data different from the first hue by a second hue angle different from the first hue angle;

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein hue shift and conversion characteristics in said first and second hue conversion steps are determined by setting of a printer driver.

46. An image processing apparatus comprising:

first hue conversion means for shifting image data having a first hue by a first hue angle;

second hue conversion means for shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

conversion means for converting at least lightness or saturation of the image data converted by said first and second hue conversion means in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein hue shift and conversion characteristics to be used by said first and second hue conversion means are determined by setting of a printer driver.

47. A storage medium storing a program which comprises:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein hue shift and conversion characteristics to be used in said first and second hue conversion steps are determined by setting of a printer driver.

48. A program comprising:

a first hue conversion step, of shifting image data having a first hue by a first hue angle;

a second hue conversion step, of shifting the image data having a second hue different from the first hue by a second hue angle different from the first hue angle; and

a conversion step, of converting at least lightness or saturation of the image data converted in said first and second hue conversion steps in accordance with conversion characteristics determined by hue angles of the image data after the hue conversion,

wherein hue shift and conversion characteristics to be used in said first and second hue conversion steps are determined by setting of a printer driver.

49. An image processing method, comprising the steps of changing independently component values of hue and saturation of an input image represented by image data,

wherein a change amount of the hue is made different at each hue angle and a change amount of the saturation is made different at each hue angle and each saturation value, and

wherein the input image is approximated to stored colors or stored colors of the input image are emphasized according to the changes of the hue and the saturation.

50. An image processing method according to claim 49, wherein lightness of which the change amount is made different at each hue angle is converted.

51. An image processing method according to claim 49, wherein the hue angle is divided into a plurality of hue angle groups, a target hue value is set to each hue value in each divided hue angle group, and each hue value is divided.

52. An image processing method according to claim 49, wherein the saturation value is partitioned into a plurality of sections for each hue angle in each divided hue angle group, a target saturation value is set to each saturation value partitioned, and each saturation value is converted.

53. An image processing method according to claim 49, wherein a color table is formed by converting the hue and the saturation on the basis of a certain color space.