Image processing method, image processing apparatus and computer program

• US 8,363,270 B2
• Filed: 04/24/2009
• Issued: 01/29/2013
• Est. Priority Date: 04/30/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hanamoto, Takashi
• Primary Examiner(s): Nguyen, Madelein A
• Application Number:
  US12/429,291
• Publication Number:
  US 20090273819A1
• Time in Patent Office: 1,376 Days
• Field of Search: 358/1.9, 358/509, 358/515, 358/518, 345/48, 345/690, 345/697
• US Class Current: 358/1.9
• CPC Class Codes: G06T 15/50 Lighting effects
• CPC Class Codes: H04N 1/60 Colour correction or control H04N1/54 takes precedence
• CPC Class Codes: H04N 1/6052 Matching two or more picture signal generators or two or more picture reproducers
• CPC Class Codes: H04N 1/6077 Colour balance, e.g. colour cast correction
• CPC Class Codes: H04N 1/6097 depending on the characteristics of the output medium, e.g. glossy paper, matt paper, transparency or fabrics

Abstract

An image processing method displays a simulation image of an image formed on a print medium under a first light-source color on a display under a second light-source color. The method includes an acquisition step of acquiring image data to be simulated in a format according to the second light-source color, a step of calculating a reflective color obtained when the acquired image data is processed to represent an image corresponding to the image data illuminated by an achromatic light-source color, a step of converting the first light-source color into the format according to the second light-source color, and calculating a glossy color of the image data based on the converted first light-source color, and a generation step of generating an image to be displayed by adding the reflective color calculated in the reflective color calculation step and the glossy color calculated in the glossy color calculation step.

Claims

1. An image processing method for displaying a simulation image of an image formed on a print medium under a first light-source color on a display device under a second light-source color, comprising:

an acquisition step of acquiring image data to be simulated in a format according to the second light-source color;

a reflective color calculation step of calculating a reflective color obtained by processing the acquired image data so that the processed image data represents an image corresponding to the acquired image data illuminated by an achromatic light-source color;

a glossy color calculation step of converting the first light-source color into the format according to the second light-source color, and calculating a glossy color of the image data based on the converted first light-source color; and

a generation step of generating the simulation image to be displayed by adding the reflective color calculated in the reflective color calculation step and the glossy color calculated in the glossy color calculation step.

2. The method according to claim 1, wherein the acquisition step includes:

a first color conversion step of applying color conversion according to the first light-source color to the image data; and

a second color conversion step of applying color conversion according to the second light-source color to the image data which has undergone the color conversion in the first color conversion step.

3. The method according to claim 1, wherein the achromatic light-source color is set as a white point corresponding to the second light-source color.

4. The method according to claim 1, wherein in the reflective color calculation step, the reflective color is calculated based on a diffuse reflection model.

5. The method according to claim 1, wherein in the glossy color calculation step, the glossy color of the image data is calculated based on a glossy reflection model.

6. The method according to claim 1, further comprising:

a peripheral image acquisition step of acquiring peripheral image data representing objects to be displayed around the simulated image at the time of simulation;

a peripheral reflective color calculation step of calculating a reflective color to be obtained when the peripheral image data is processed to represent a peripheral image illuminated under the first light-source color;

a peripheral glossy color calculation step of calculating a glossy color of the peripheral image data based on the first light-source color;

a display peripheral image generation step of generating the peripheral image to be displayed by adding the reflective color calculated in the peripheral reflective color calculation step and the glossy color calculated in the peripheral glossy color calculation step;

a display peripheral image conversion step of converting the peripheral image to be displayed into the format according to the second light-source color; and

a composition step of compositing the converted peripheral image to be displayed on the simulation image to be displayed.

7. The method according to claim 6, wherein the peripheral image data represents a three-dimensional object generated using computer graphics.

8. An image processing method for displaying an image formed on a print medium, which is observed under a first light-source color, on a display device under a second light-source color, so as to simulate the image, comprising:

an acquisition step of acquiring image data to be simulated in a format according to the first light-source color;

a reflective color calculation step of calculating a reflective color obtained by processing the acquired image data so that the processed image data represents an image corresponding to the acquired image data illuminated by an achromatic light-source color;

a glossy color calculation step of calculating a glossy color of the image data based on the first light-source color;

an addition step of generating an addition image by adding the reflective color calculated in the reflective color calculation step and the glossy color calculated in the glossy color calculation step; and

a generation step of generating the simulation image to be displayed by converting the addition image into the format according to the second light-source color.

9. A computer program, stored in a non-transitory computer readable storage medium, causing a computer to execute an image processing method for displaying a simulation image of an image formed on a print medium under a first light-source color on a display device under a second light-source color, said method comprising:

an acquisition step of acquiring image data to be simulated in a format according to the second light-source color;

a reflective color calculation step of calculating a reflective color obtained by processing the acquired image data so that the processed image data represents an image corresponding to the acquired image data illuminated by is an achromatic light-source color;

a glossy color calculation step of converting the first light-source color into the format according to the second light-source color, and calculating a glossy color of the image data based on the converted first light-source color; and

a generation step of generating the simulation image to be displayed by adding the reflective color calculated in the reflective color calculation step and the glossy color calculated in the glossy color calculation step.

10. An image processing apparatus for reproducing a simulation image of an image formed on a print medium under a first light-source color on a display device under a second light-source color, comprising:

an acquisition unit configured to acquire image data according to the second light-source color;

a lighting processing unit configured to apply lighting processing using an achromatic light-source color to the acquired image data according to the second light-source color;

a conversion unit configured to convert the first light-source color based on the second light-source color; and

a gloss addition processing unit configured to execute processing for adding gloss to the image data that has undergone the lighting processing, based on the converted first light-source color.