Image processing apparatus, image processing method, image processing program, storage medium and computer data signal

Abstract

An image processing apparatus performs color conversion processing on an input image. The image processing apparatus includes a reducing unit, a first color converting unit and an enlarging unit. The reducing unit reduces the input image. The first color converting unit performs color conversion on the image reduced by the reducing unit. The enlarging unit enlarges the image color-converted by the first color converting unit.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will be described in detail based on the following figures, wherein:

FIG. 1 is a block diagram showing a first exemplary embodiment of the invention;

FIG. 2 is an explanatory diagram showing a specific example of the operation of the first exemplary embodiment of the invention;

FIG. 3 is a block diagram showing an example of an attribute judgment section;

FIG. 4 is a block diagram showing a second exemplary embodiment of the invention;

FIG. 5 is a block diagram showing a modification of the second exemplary embodiment of the invention;

FIG. 6 is a block diagram showing another modification of the second exemplary embodiment of the invention;

FIG. 7 is a block diagram showing a third exemplary embodiment of the invention;

FIG. 8 is an explanatory diagram showing a computer program as an implementation of the functions of the image processing apparatus according to the exemplary embodiments of the invention or the image processing method according to the exemplary embodiments of the invention as well as exemplary storage media in which the computer program is stored; and

FIG. 9 illustrates an exemplary color conversion method using a DLUT.

Claims

1. An image processing apparatus for performing color conversion processing on an input image, the image processing apparatus comprising: a reducing unit that reduces the input image;a first color converting unit that performs color conversion on the image reduced by the reducing unit; andan enlarging unit that enlarges the image color-converted by the first color converting unit.

2. The apparatus according to claim 1, further comprising: a second color converting unit that performs color conversion on the input image; andan output image generating unit that generates an output image based on at least one of the image enlarged by the enlarging unit and the image color-converted by the second color converting unit.

3. An image processing apparatus for performing color conversion processing on an input image, the image processing apparatus comprising: a reducing unit that reduces the input image;a first color converting unit that performs color conversion on the image reduced by the reducing unit;an enlarging unit that enlarges the image color-converted by the first color converting unit;a second color converting unit that performs color conversion on the input image; andan output image generating unit that generates an output image based on at least one of the image enlarged by the enlarging unit and the image color-converted by the second color converting unit, wherein:the second color converting unit performs the color conversion according to a color conversion method, which requires a less calculation amount than a color conversion method of the first color converting unit.

4. The apparatus according to claim 2, further comprising: a filtering unit that performs adaptive filtering on the input image, the adaptive filtering that emphasizes an edge contained in the input image, wherein:the second color converting unit performs the color conversion on the image filtered by the filtering unit.

5. The apparatus according to claim 2, further comprising: an attribute judging unit that judges an attribute of each region of the input image, wherein:the output image generating unit selects for each region either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with the attribute of the corresponding region judged by the attribute judging unit, to generate the output image.

6. The apparatus according to claim 5, wherein the attribute judging unit detects an edge amount in the input image and judges the attribute of each region using the detected edge amount.

7. The apparatus according to claim 5, wherein: the attribute judging unit comprises: a first judging unit that judges the attribute of each region; anda second judging unit that judges an attribute of one region if the first judging unit cannot judge the attribute of the one region, andjudgment processing performed by the first judging unit is simpler than that performed by the second judging unit.

8. The apparatus according to claim 7, wherein: the first judging unit judges the attribute of each region using a first edge detection filter,the second judging unit judges the attribute of the one region using a second edge detection filter, anda size of the second detection filter is larger than that of the first detection filter.

9. The apparatus according to claim 4, further comprising: an attribute judging unit that judges an attribute of each region of the input image, wherein:the output image generating unit selects for each region either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with the attribute of the corresponding region judged by the attribute judging unit, to generate the output image,the attribute judging unit comprises: a first judging unit that judges the attribute of each region; anda second judging unit that judges an attribute of one region if the first judging unit cannot judge the attribute of the one region,judgment processing performed by the first judging unit is simpler than that performed by the second judging unit,the filtering unit performs first filtering if the first judging unit of the attribute judging unit judges that the attribute of the one region is one, which requires the color conversion of the second color converting unit,the filtering unit performs second filtering if the second judging unit judges that the attribute of the one region is one, which requires the color conversion of the second color converting unit, andthe second filtering involves a larger processing amount than the first filtering.

10. The apparatus according to claim 5, wherein: the input image is data written in printer description language, andthe attribute judging unit interprets the data written in the printer description language to judge the attribute of each region.

11. The apparatus according to claim 5, wherein: the output image generating unit selects the image color-converted by the second color converting unit, for a region, which the attribute judging unit judges as a text/line-drawing region, andthe output image generating unit selects the image enlarged by the enlarging unit, for a region, which the attribute judging unit judges as a photograph region.

12. The apparatus according to claim 2, wherein the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with a processing mode, to generate the output image.

13. The apparatus according to claim 2, wherein the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with a document mode, to generate the output image.

14. The apparatus according to claim 2, wherein the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with a color mode, to generate the output image.

15. The apparatus according to claim 4, wherein: the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with a color mode, to generate the output image, andthe output image generating unit selects the image, which is filtered by the filtering unit and not subjected to the color conversion of the second color converting unit if the color mode is a black-and-white mode.

16. The apparatus according to claim 2, wherein the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with a processing speed mode indicating whether priority is attached to the processing speed or the image quality, to generate the output image.

17. The apparatus according to claim 2, wherein the output image generating unit selects either the image enlarged by the enlarging unit or the image color-converted by the second color converting unit in accordance with system resource situations of the apparatus, to generate the output image

18. The apparatus according to claim 1, wherein: the reducing unit changes a reducing algorithm or a reduction factor in accordance with a processing mode, andthe enlarging unit changes an enlarging algorithm or a enlargement factor in accordance with the processing mode.

19. An image processing method for performing color conversion processing on an input image, the method comprising: reducing the input image;performing first color conversion on the reduced image; andenlarging the image subjected to the first color conversion.

20. The method according to claim 19, further comprising: performing second color conversion on the input image; andgenerating an output image based on at least one of the enlarged image and the image subjected to the second color conversion.

21. An image processing method for performing color conversion processing on an input image, the method comprising: reducing the input image;performing first color conversion on the reduced image;enlarging the image subjected to the first color conversion;performing second color conversion on the input image; andgenerating an output image based on at least one of the enlarged image and the image subjected to the second color conversion, wherein:the second color conversion requires a less calculation amount than the first color conversion.

22. The method according to claim 20, further comprising: performing adaptive filtering on the input image, the adaptive filtering that emphasizes an edge contained in the input image, wherein:the second color conversion is performed on the image subjected to the adaptive filtering.

23. The method according to claim 20, further comprising: judging an attribute of each region of the input image, wherein:the generating of the output image comprises selecting for each region either the enlarged image or the image subjected to the second color conversion in accordance with the judged attribute of the corresponding region.

24. The method according to claim 23, further comprising: detecting an edge amount in the input image, wherein:the attribute of each region is judged using the detected edge amount.

25. The method according to claim 23, wherein: the judging of the attribute of each region comprises: performing a first judgment processing on each region of the input image to judge the attribute of each region; andperforming a second judgment processing on one region to judge an attribute of the one region if the first judgment processing cannot judge the attribute of the one region, andthe first judgment processing is simpler than the second judgment processing.

26. The method according to claim 25, wherein: the first judgment processing uses a first edge detection filter,the second judgment processing uses a second edge detection filter, anda size of the second edge detection filter is larger than that of the first edge detection filter.

27. The method according to claim 22, further comprising: judging an attribute of each region of the input image, wherein:the generating of the output image comprises selecting for each region either the enlarged image or the image subjected to the second color conversion in accordance with the judged attribute of the corresponding region,the judging of the attribute of each region comprises: performing a first judgment processing on each region of the input image to judge the attribute of each region; andperforming a second judgment processing on one region to judge an attribute of the one region if the first judgment processing cannot judge the attribute of the one region, andthe first judgment processing is simpler than the second judgment processing,the adaptive filtering comprises:performing first filtering if a result of the first judgment processing indicates that the attribute of the one region is one, which requires the second color conversion,performing second filtering if a result of the second judgment processing indicates that the attribute of the one region is one, which requires the second color conversion, andthe second filtering involves a larger processing amount than the first filtering.

28. The method according to claim 23, wherein: the input image is data written in printer description language, andthe judging of the attribute of each region comprises interpreting the data written in the printer description language to judge the attribute of each region.

29. The method according to claim 23, wherein: the selecting of either the enlarged image or the image subjected to the second color conversion comprises: selecting the image subjected to the second color conversion for a region, which a result of the judging indicates as a text/line-drawing region, andselecting the enlarged image for a region, which the result of the judging indicates as a photograph region.

30. The method according to claim 20, wherein the selecting of either the enlarged image or the image subjected to the second color conversion comprises selecting either the image enlarged or the image subjected to the second color conversion in accordance with a processing mode.

31. The method according to claim 20, wherein the selecting of either the enlarged image or the image subjected to the second color conversion comprises selecting either the image enlarged or the image subjected to the second color conversion in accordance with a document mode.

32. The method according to claim 20, wherein the selecting of either the enlarged image or the image subjected to the second color conversion comprises selecting either the image enlarged or the image subjected to the second color conversion in accordance with a color mode.

33. The method according to claim 22, wherein: the generating of the output image comprises selecting either the enlarged image or the image subjected to the second color conversion in accordance with a color mode, andthe selecting selects the image, which is subjected to the adaptive filtering and not subjected to the second color conversion if the color mode is a black-and-white mode.

34. The method according to claim 20, wherein the generating of the output image comprises selecting either the enlarged image or the image subjected to the second color conversion in accordance with a processing speed mode of an apparatus which performs the color conversion processing, the processing speed mode indicating whether priority is attached to the processing speed or the image quality.

35. The method according to claim 20, wherein the generating of the output image comprises selecting either the enlarged image or the image subjected to the second color conversion in accordance with a system resource situations of an apparatus, which performs the conversion processing.

36. The method according to claim 19, wherein: the reducing changes a reducing algorithm or a reduction factor in accordance with a processing mode, andthe enlarging changes an enlarging algorithm or a enlargement factor in accordance with the processing mode.

37. A computer readable medium storing a program causing a computer to execute a process for performing color conversion processing on an input image, the process comprising: reducing the input image;performing first color conversion on the reduced image; andenlarging the image subjected to the first color conversion.

38. A computer data signal embodied in a carrier wave for enabling a computer to perform a process for performing color conversion processing on an input image, the process comprising: reducing the input image;performing first color conversion on the reduced image; andenlarging the image subjected to the first color conversion.