Image processing apparatus, image forming apparatus, image processing method, and non-transitory computer readable storage medium configured to generate, based on correction data, data indicating on dot positions during printing and scanning

Patent metadata

Field	Value
Publication number	US-9894250-B2
Application number	US-201615239252-A
Country	US
Kind code	B2
Filing date	Aug 17, 2016
Priority date	Aug 27, 2015
Publication date	Feb 13, 2018
Grant date	Feb 13, 2018

Abstract

A unit acquires first image data expressing a color of an image and second image data expressing a feature of the image. A unit color-separates the first image data into first and second color material amount data. A unit generates inverted data by inverting the second image data. A unit generates first corrected data from the first color material amount data and the inverted data and generates second corrected data from the second color material amount data and the second image data. A unit generates, based on the first corrected data, first data indicating on dot printing positions during a printing and scanning operation, generates, based on the second corrected data, second data indicating on dot printing positions in the operation, and generates, based on the first and second data, image forming data.

First claim

What is claimed is:

1. An image processing apparatus comprising:
at least one processor; and
a memory having stored thereon instructions which, when executed by the at least one processor, cause the apparatus to:
acquire first image data expressing a color of an image to be formed and second image data expressing a feature of the image;
color-separate the first image data into first color material amount data and second color material amount data;
generate inverted data acquired by inverting the second image data;
generate first corrected color material amount data from the first color material amount data and the inverted data and generate second corrected color material amount data from the second color material amount data and the second image data; and
generate, based on the first corrected color material amount data, first data indicating on dot printing positions during a printing and scanning operation of an image forming apparatus, generate, based on the second corrected color material amount data, second data indicating on dot printing positions in the printing and scanning operation, and generate, based on the first data and the second data, image forming data to be output to the image forming apparatus.

2. The apparatus according to claim 1 , wherein the feature of the image is sharpness, the first color material amount data is color material amount data to reproduce low-sharpness, and the second color material amount data is color material amount data to reproduce high-sharpness.

3. The apparatus according to claim 1 , wherein the feature of the image is a degree of glossiness, the first color material amount data is low-gloss color material amount data to reproduce low-gloss, and the second color material amount data is high-gloss color material amount data to reproduce high-gloss.

4. The apparatus according to claim 3 , wherein the execution of the instructions by the at least one processor further causes the apparatus to generate the low-gloss color material amount data by referring to a color separation characteristic table which uses many dark color materials and generates the high-gloss color material amount data by referring to a color separation characteristic table which uses many light color materials.

5. The apparatus according to claim 3 , wherein the execution of the instructions by the at least one processor further causes the apparatus to generate the first corrected color material amount data by normalizing, based on a number of tones, a multiplication result of the low-gloss color material amount data and the inverted data for each pixel and generates the second corrected color material amount data by normalizing, based on the number of tones, a multiplication result of the high-gloss color material amount data and the second image data for each pixel.

6. The apparatus according to claim 3 , wherein the execution of the instructions by the at least one processor further causes the apparatus to:
correct, based on a gloss reproducible range corresponding to color image data acquired as the first image data, gloss image data acquired as the second image data.

7. The apparatus according to claim 6 , wherein the execution of the instructions by the at least one processor further causes the apparatus to perform the correction by using a gloss reproducible range table which indicates a low-gloss value corresponding to minimum gloss image data and a high-gloss value corresponding to maximum gloss image data that are reproducible for each of the color image data.

8. The apparatus according to claim 7 , wherein the execution of the instructions by the at least one processor further causes the apparatus to correct the gloss image data of a pixel of interest based on a minimum value of the low-gloss value, a maximum value of the high-gloss value, a low-gloss value and a high-gloss value corresponding to the color image data of the pixel of interest, and a maximum value of the acquired gloss image data which are obtained from the gloss reproducible range table.

9. The apparatus according to claim 6 , wherein the execution of the instructions by the at least one processor further causes the apparatus to:
correct the color image data and generate low-gloss image data and high-gloss image data, and
color-separate the low-gloss image data into the low-gloss color material amount data and the high-gloss image data into the high-gloss color material amount data.

10. The apparatus according to claim 9 , wherein the execution of the instructions by the at least one processor further causes the apparatus to perform the correction using a color gloss table indicating correspondence between a color gloss indicated by a combination of the color image data and the acquired gloss image data, a low-gloss color gamut indicating a color gloss reproducible range by the first data, and a high-gloss color gamut indicating a color gloss reproducible range by the second data.

11. The apparatus according to claim 10 , wherein the color gloss table includes a first table indicating the low-gloss color gamut gloss image data and the high-gloss color gamut gloss image data which correspond to the color gloss indicated by the combination of the color image data and the gloss image data and a second table indicating the low-gloss color gamut color image data and the high-gloss color gamut color image data which correspond to the color gloss, and
the first table is used for the correction based on a gloss reproducible range corresponding to color image data acquired as the first image data, gloss image data acquired as the second image data, and the second table is used for the correction of the color image data and for generating low-gloss image data and high-gloss image data.

12. The apparatus according to claim 1 , wherein the execution of the instructions by the at least one processor further causes the apparatus to determine, in the generation of the first data, the number of on dots in the printing and scanning operation and determines on dot positions based on cell values of a dither matrix.

13. The apparatus according to claim 12 , wherein the execution of the instructions by the at least one processor further causes the apparatus to determine, in the generation of the second data, the number of on dots in the printing and scanning operation, determines the on dot positions based on the cell values of the dither matrix, and updates the values of the respective cells of the dither matrix corresponding to the determined on dot positions.

14. The apparatus according to claim 13 , wherein the update is performed by adding, to each of the cell values, one of the number of cells of the dither matrix and a value which is not less than a maximum value of cells.

15. The apparatus according to claim 1 , wherein the execution of the instructions by the at least one processor further causes the apparatus to determine, in the generation of the first data, the number of on dots in the printing and scanning operation, determines on dot positions based on cell values of a dither matrix, and updates the values of the respective cells of the dither matrix corresponding to the determined on dot positions.

16. The apparatus according to claim 15 , wherein the execution of the instructions by the at least one processor further causes the apparatus to determine, in the generation of the second data, the number of on dots in the printing and scanning operation, determines the on dot positions based on the updated cell values of the dither matrix, and updates the values of the respective cells of the dither matrix corresponding

Assignees

• Canon Kk

Inventors

• Moribe Shoei

Classifications

• H04N1/6019

  using look-up tables (H04N1/6025 takes precedence) · CPC title

• H04N2201/0082

  Image hardcopy reproducer (H04N2201/0091 - H04N2201/0094 take precedence) · CPC title

• H04N1/6066 Primary

  dependent on the gamut of the image to be reproduced · CPC title

• H04N1/52 Primary

  Circuits or arrangements for halftone screening · CPC title

• H04N1/502

  Reproducing the colour component signals dot-sequentially or simultaneously in a single or in adjacent picture-element positions · CPC title