IMAGE PROCESSING METHOD

• US 20100104176A1
• Filed: 10/15/2009
• Published: 04/29/2010
• Est. Priority Date: 10/24/2008
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Hayase, Yosuke
• Granted Patent: US 8,488,905 B2
• Time in Patent Office: Days
• US Class Current: 382/162
• CPC Class Codes: H04N 1/3871 the composed originals being of different kinds, e.g. low- and high-resolution originals
• CPC Class Codes: H04N 1/6088 by viewing conditions, i.e. conditions at picture output
• CPC Class Codes: H04N 9/3182 Colour adjustment, e.g. white balance, shading or gamut white balance per se H04N9/73; control of amplitude of colour signals H04N9/68; colour control circuits for displays in general G09G5/02, G09G3/2003, G09G3/3607
• CPC Class Codes: H04N 9/67 for matrixing camera processing pipelines for matrixing of colour signals H04N23/85

Abstract

It is difficult to reproduce an input image more faithfully while enlarging a dynamic range and color gamut, in a reproduced image obtained by overlapping output images by a projector and printer. An image processing apparatus (102) transforms an input signal (101) into an RGB signal for a projector (103) and a CMY signal for a printer (104). In this case, the image processing apparatus (102) uses a transformation LUT, which is generated based on the spectral distribution characteristics of the projector (103) and the spectral reflectivity characteristics of the printer (104). By overlapping images formed by the projector (103) and printer (104) based on the transformed image signals, an input image can be reproduced more faithfully while enlarging the dynamic range and color gamut.

Claims

1. An image processing method for reproducing one image by overlapping output images by first and second devices having different output modes, comprising:

an input step of inputting an image signal to be reproduced;

a device image generation step of generating, from the input image signal, a first image signal for the first device and a second image signal for the second device; and

an output step of outputting the first image signal to the first device and the second image signal to the second device.

2. The method according to claim 1, wherein in the device image generation step, the first and second image signals are generated based on a spectroscopic characteristics associated with the first device and a spectroscopic characteristics associated with the second device.

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

a storage step of storing a transformation table, which is created based on a spectroscopic characteristics associated with the first device, a spectroscopic characteristics associated with the second device, and a color-matching function,

wherein in the device image generation step, the image signal input in the input step is transformed into the first and second image signals using the table stored in the storage step.

4. The method according to claim 3, wherein the first device is a light-emitting type device which allows a user to observe an image formed by self emission, and

the second device is a reflection type device which allows the user to observe reflected light from an image formed on a medium.

5. The method according to claim 4, wherein the first device is a projector, and

the second device is a printer.

6. The method according to claim 5, wherein the spectroscopic characteristics associated with the first device is a spectral distribution characteristics of projection light of the projector, and

the spectroscopic characteristics associated with the second device is a spectral reflectivity characteristics of printed matter of the printer.

7. The method according to claim 3, wherein in the storage step, a transformation table, which is created based on the spectroscopic characteristics associated with the first device, the spectroscopic characteristics associated with the second device, a spectroscopic characteristics of an observation illumination, and the color-matching function, is stored.

8. The method according to claim 7, wherein in the storage step, a plurality of tables, which are respectively created according to different observation illuminations, are stored,

the method further comprises a table selection step of selecting an appropriate table from the storage step according to information of an actual observation illumination, and

in the device image generation step, the image signal input in the input step is transformed into the first and second image signals using the table selected in the table selection step.

9. The method according to claim 3, wherein the table is created using a virtual three-dimensional color space upon overlapping output images by the first and second devices.

10. The method according to claim 9, wherein the table is created so that one of the first device and the second device attaches importance to color reproduction, and the other attaches importance to luminance correction.

11. The method according to claim 9, wherein the table is created so that the first device reproduces colors whose brightness is higher than a predetermined threshold, and the second device reproduces colors whose brightness is not more than the threshold.

12. The method according to claim 7, wherein in the storage step, a plurality of tables respectively having different properties are stored in correspondence with sole use modes and an overlap use mode of the first and second devices,

the method further comprises a table selection step of selecting an appropriate table from the storage step in accordance with a use mode of the first and second devices for each type of an object in an image, and

in the device image generation step, the image signal input in the input step is transformed into the first and second image signals using the table selected in the table selection step.

13. The method according to claim 12, wherein in the table selection step, the use mode of the first and second devices and the table according to the use mode are selected for each type of an object in an image based on a user instruction.

16. A program for making a computer function as respective steps of an image processing method according to claim 1.

17. A computer-readable storage medium storing a program according to claim 16.

14. An image processing method for generating images respectively for first and second devices so as to reproduce one image by overlapping output images by the first and second devices having different output modes, comprising:

an input step of inputting an image signal to be reproduced; and

a device image generation step of generating, from the input image signal, a first image signal for the first device and a second image signal for the second device,

wherein in the device image generation step, the first and second image signals are generated based on a spectroscopic characteristics associated with the first device and a spectroscopic characteristics associated with the second device.

15. The method according to claim 14, further comprising a step of creating a transformation table based on the spectroscopic characteristics associated with the first device, the spectroscopic characteristics associated with the second device, and a color-matching function,

wherein in the device image generation step, the image signal input in the input step is transformed into the first and second image signals using the table.