COLOR PROCESSING APPARATUS, AND METHOD THEREFOR

• US 20110007333A1
• Filed: 06/25/2010
• Published: 01/13/2011
• Est. Priority Date: 07/13/2009
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hanamoto, Takashi, Ishii, Masatoshi
• Granted Patent: US 8,493,618 B2
• Time in Patent Office: Days
• US Class Current: 358/1.9
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence
• CPC Class Codes: H04N 1/6033 using test pattern analysis H04N1/6055 takes precedence

Abstract

A color processing apparatus configured to simulate a print product output by a printer on a monitor. The apparatus includes a first conversion unit configured to convert color data representing an image of the simulation object into color data in a printer color space, a first calculation unit configured to calculate color data of diffuse reflection in a line-of-sight direction from color data in the printer color space, a second calculation unit configured to calculate color data in the printer color space and specular reflection color data, a third calculation unit configured to calculate color data of specular reflection in a line-of-sight direction from color data of specular reflection calculated using a parameter representing an exitance of the glossiness and colorless light-source color data, a combination unit configured to combine the color data of diffuse reflection and color data of specular reflection, and a second conversion unit configured to convert the combined color data to color data in the monitor color space.

Claims

1. A color processing apparatus configured to simulate a print product output by a printer on a monitor, the color processing apparatus comprising:

a first conversion unit configured to convert color data representing an image of the simulation object into color data in a printer color space based on an illumination condition and a printer profile;

a first calculation unit configured to calculate color data of diffuse reflection in a line-of-sight direction from color data in the printer color space using a diffuse reflection table corresponding to the illumination condition;

a second calculation unit configured to calculate color data in the printer color space and specular reflection color data using a specular reflection table corresponding to the illumination condition;

a third calculation unit configured to calculate color data of specular reflection in a line-of-sight direction from color data of specular reflection calculated using a parameter representing an exitance of the glossiness and colorless light-source color data;

a combination unit configured to combine the color data of diffuse reflection in a line-of-sight direction and color data of specular reflection in a line-of-sight direction; and

a second conversion unit configured to convert the combined color data to color data in a color space of the monitor.

2. The color processing apparatus according to claim 1, wherein a parameter representing the exitance of the glossiness, a specular reflection table and a diffuse reflection table are produced by measuring the extent of the reflected light, the spectral reflectance in the specular direction and the spectral reflectance in the diffuse direction with reference to a patch output by the printer.

3. A method for simulating a print product output by a printer on a monitor, the method comprising:

converting color data representing an image of the simulation object into color data in a printer color space based on an illumination condition and a printer profile;

calculating color data of diffuse reflection in a line-of-sight direction from color data in the printer color space using a diffuse reflection table corresponding to the illumination condition;

calculating color data in the printer color space and specular reflection color data using a specular reflection table corresponding to the illumination condition;

calculating color data of specular reflection in a line-of-sight direction from color data of specular reflection calculated using a parameter representing the exitance of the glossiness and colorless light-source color data;

combining the color data of diffuse reflection in a line-of-sight direction and color data of specular reflection in a line-of-sight direction; and

converting the combined color data to color data in a color space of the monitor.

4. A computer-readable storage medium storing a program of computer-executable instructions which cause a color processing apparatus configured to simulate a print product output by a printer on a monitor, the program of computer-executable instructions comprising:

computer-executable instructions which convert color data representing an image of the simulation object into color data in a printer color space based on an illumination condition and a printer profile;

computer-executable instructions which calculate color data of diffuse reflection in a line-of-sight direction from color data in the printer color space using a diffuse reflection table corresponding to the illumination condition;

computer-executable instructions which calculate color data in the printer color space and specular reflection color data using a specular reflection table corresponding to the illumination condition;

computer-executable instructions which calculate color data of specular reflection in a line-of-sight direction from color data of specular reflection calculated using a parameter representing the exitance of the glossiness and colorless light-source color data;

computer-executable instructions which combine the color data of diffuse reflection in a line-of-sight direction and color data of specular reflection in a line-of-sight direction; and

computer-executable instructions which convert the combined color data to color data in a color space of the monitor.