IMAGE PROCESSING APPARATUS AND METHOD

• US 20070243314A1
• Filed: 04/06/2007
• Published: 10/18/2007
• Est. Priority Date: 04/12/2006
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Jinno, Takayuki
• Granted Patent: US 8,027,058 B2
• Time in Patent Office: Days
• US Class Current: 427/8
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence
• CPC Class Codes: H04N 1/6022 Generating a fourth subtractive colour signal, e.g. under colour removal, black masking
• CPC Class Codes: H04N 1/6097 depending on the characteristics of the output medium, e.g. glossy paper, matt paper, transparency or fabrics

Abstract

A color region in which the difference of a bronzing between different colors is to be decreased is set in accordance with preset printing conditions, and a bronzing of a printing medium with a predetermined chromaticity is measured. The measured bronzing measurement value is held, and color separation data to decrease the difference of the measurement value between the different colors in the color region is generated based on the held bronzing measurement value.

Claims

1. An image processing method of generating, for a predetermined gamut, color separation data corresponding to a color material used in a printing apparatus, comprising:

a color region setting step of setting, in accordance with a preset printing condition, a color region in which a difference of a bronzing between different colors is to be decreased;

a bronzing measurement step of measuring a bronzing of a printing medium with a predetermined chromaticity;

a bronzing holding step of holding a bronzing measurement value measured in the bronzing measurement step; and

a color separation data generation step of generating color separation data to decrease a difference of the bronzing measurement value between different colors in the color region on based on the bronzing measurement value held in the bronzing holding step.

2. The method according to claim 1, wherein a tint of specular reflected light from the printing medium is measured in the bronzing measurement step.

3. The method according to claim 1, wherein the printing condition includes information of a color region which is set in the color region setting step and in which a difference of a bronzing is to be decreased.

4. An image processing apparatus which converts image data into printing data for a printing apparatus by using color separation data and outputs the printing data, comprising:

a storage unit adapted to store characteristic data of a plurality of images printed under a plurality of printing conditions including a printing condition acceptable by the printing apparatus;

a color distribution generation unit adapted to generate a color distribution based on each pixel data value of input image data; and

a color separation data generation unit adapted to generate color separation data by extracting from the storage unit characteristic data to decrease a difference of a bronzing of an image to be printed, in accordance with a printing condition for printing an image by the printing apparatus and a color distribution of the input image data.

6. The apparatus according to claim 4, further comprising:

a bronzing measurement unit adapted to measure a bronzing of each image printed using a plurality of color materials on a plurality of printing media with a plurality of chromaticities; and

a unit adapted to generate, based on a bronzing measurement value measured by said bronzing measurement unit, the characteristic data to decrease a difference between the bronzing measurement value and image data corresponding to said each image.

7. The apparatus according to claim 6, wherein said bronzing measurement unit measures a tint of specular reflected light from the printing media.

8. The apparatus according to claim 4, wherein the printing condition includes at least one of a kind of a printing medium and a kind of a color material used in printing onto the printing medium.

9. The apparatus according to claim 4, further comprising a user interface to designate the printing condition.

5. An image processing apparatus which converts image data into printing data for a printing apparatus by using color separation data and outputs the printing data, comprising:

a storage unit adapted to store characteristic data of a plurality of images printed under a plurality of printing conditions including a printing condition acceptable by the printing apparatus;

an indication unit adapted to indicate an attribute of an input image; and

a color separation data generation unit adapted to generate color separation data by extracting from said storage unit characteristic data to decrease a difference of a bronzing of an image to be printed, in accordance with a printing condition for printing an image by the printing apparatus and the attribute of the image indicated by said indication unit.

16. The apparatus according to claim 5, further comprising:

a bronzing measurement unit adapted to measure a bronzing of each image printed using a plurality of color materials on a plurality of printing media with a plurality of chromaticities; and

a unit adapted to generate, based on a bronzing measurement value measured by said bronzing measurement unit, the characteristic data to decrease a difference between the bronzing measurement value and image data corresponding to said each image.

17. The apparatus according to claim 16, wherein said bronzing measurement unit measures a tint of specular reflected light from the printing media.

18. The apparatus according to claim 5, wherein the printing condition includes at least one of a kind of a printing medium and a kind of a color material used in printing onto the printing medium.

19. The apparatus according to claim 5, further comprising a user interface to designate the printing condition.

10. An image processing method of converting image data into printing data for a printing apparatus by using color separation data and outputting the printing data, comprising:

a color distribution generation step of generating a color distribution based on each pixel data value of input image data; and

a color separation data generation step of generating color separation data by extracting, from a memory storing characteristic data of a plurality of images printed under a plurality of printing conditions including a printing condition acceptable by the printing apparatus, characteristic data to decrease a difference of a bronzing of an image to be printed, in accordance with a printing condition for printing an image by the printing apparatus and a color distribution of the input image data.

12. The method according to claim 10, further comprising:

a bronzing measurement step of measuring a bronzing of each image printed using a plurality of color materials on a plurality of printing media with a plurality of chromaticities; and

a step of generating, based on a bronzing measurement value measured in the bronzing measurement step, the characteristic data to decrease a difference between the bronzing measurement value and image data corresponding to said each image.

13. The method according to claim 12r wherein a tint of specular reflected light from the printing media is measured in the bronzing measurement step.

14. The method according to claim 10, wherein the printing condition includes at least one of a kind of a printing medium and a kind of a color material used in printing onto the printing medium.

15. The method according to claim 10, further comprising a step of providing a user interface to designate the printing condition.

11. An image processing method of converting image data into printing data for a printing apparatus by using color separation data and outputting the printing data, comprising:

an indication step of indicating an attribute of an input image; and

a color separation data generation step of generating color separation data by extracting, from a memory storing characteristic data of a plurality of images printed under a plurality of printing conditions including a printing condition acceptable by the printing apparatus, characteristic data to decrease a difference of a bronzing of an image to be printed, in accordance with a printing condition for printing an image by the printing apparatus and the attribute of the image indicated in the indication step.

20. The method according to claim 11, further comprising:

a bronzing measurement step of measuring a bronzing of each image printed using a plurality of color materials on a plurality of printing media with a plurality of chromaticities; and

a step of generating, based on a bronzing measurement value measured in the bronzing measurement step, the characteristic data to decrease a difference between the bronzing measurement value and image data corresponding to said each image.

21. The method according to claim 20, wherein a tint of specular reflected light from the printing media is measured in the bronzing measurement step.

22. The method according to claim 11, wherein the printing condition includes at least one of a kind of a printing medium and a kind of a color material used in printing onto the printing medium.

23. The method according to claim 11, further comprising a step of providing a user interface to designate the printing condition.