US5657068A
Expired / Lapsed
US
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Color image processing apparatus and conversion method
Assignee: Canon Inc
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Filing: 1993-03-29
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Granted: 1997-08-12
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Expires: 2013-03-29
Abstract
Abstract A minimum value of input color image signals (R, G, B) is extracted, difference signals between the extracted minimum value and the input signals (R, G, B) are calculated, and matrix conversion is executed based on the difference signals, thereby obtaining desired output color image signals having a color reproduction range different from that of the input color image signals.
Inventors
- 👤 Ken-ichi Ohta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:18
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6058
Claims Analysis
Total Claims: 31
Claim 1
Independent Claim
122 words
A color image processing apparatus for gamut mapping color image data into a gamut of an output device, comprising: inputting means for inputting color image data comprised of a plurality of color components; extracting means for extracting achromatic color component data which corresponds to a minimum value of the color components in the color image data; first generating means for generating difference data which defines a difference between the achromatic color component data and each of the color components of the color image data; second generating means for generating correction data for the color image data using the difference data; and gamut mapping means for gamut mapping the color image data into the gamut of the output device using the correction data.
Claim 2
Dependent Claim
122 words
A color image processing apparatus for gamut mapping color image data into a gamut of an output device, comprising: inputting means for inputting color image data comprised of a plurality of color components; extracting means for extracting achromatic color component data which corresponds to a minimum value of the color components in the color image data; first generating means for generating difference data which defines a difference between the achromatic color component data and each of the color components of the color image data; second generating means for generating correction data for the color image data using the difference data; and gamut mapping means for gamut mapping the color image data into the gamut of the output device using the correction data.
Claim 3
Dependent Claim
22 words
The apparatus according to claim 1, wherein said inputting means inputs color image data comprised of R, G, and B color signals.
Claim 4
Dependent Claim
52 words
The apparatus according to claim 1, wherein said second generating means includes conversion means for executing matrix conversion on the difference data in order to generate the correction data, and setting means for adaptively setting matrix coefficients for the matrix conversion in accordance with a color distribution of the color image data.
Claim 5
Dependent Claim
95 words
The apparatus according to claim 3, wherein the setting means comprises (1) calculating means for calculating inner products between a vector defined by predetermined chrominance signal values, and a vector defined by color signal values in the color image data, (2) detecting means for detecting a maximum value of the inner products, (3) storing means for storing the color signal values when the maximum value of the inner products is obtained, and (4) solving means for obtaining the matrix coefficients by solving simultaneous equations defined by the color signal values stored in the storing means.
Claim 6
Dependent Claim
42 words
The apparatus according to claim 1, wherein the color image data defines an object image, and wherein said gamut mapping means performs gamut mapping on the color image data so that the object image fits inside the gamut of the output device.
Claim 7
Dependent Claim
110 words
A color image processing method for gamut mapping color image data into a gamut of an output device, comprising the steps of: inputting color image data comprised of a plurality of color components; extracting achromatic color component data which corresponds to a minimum value of the color components in the color image data; generating difference data which defines a difference between the achromatic color component data and each color component of the color image data; generating correction data for the color image data using the difference data and the color image data; and gamut mapping the color image data into the gamut of the output device using the correction data.
Claim 8
Dependent Claim
110 words
A color image processing method for gamut mapping color image data into a gamut of an output device, comprising the steps of: inputting color image data comprised of a plurality of color components; extracting achromatic color component data which corresponds to a minimum value of the color components in the color image data; generating difference data which defines a difference between the achromatic color component data and each color component of the color image data; generating correction data for the color image data using the difference data and the color image data; and gamut mapping the color image data into the gamut of the output device using the correction data.
Claim 9
Dependent Claim
91 words
A color image processing apparatus for gamut mapping color image data for an object image into a gamut of an output device, comprising: inputting means for inputting color image data for the object image; detecting means for detecting a color distribution of the color image data for the object image; calculating means for calculating matrix coefficients using the color distribution detected by said detecting means; and gamut mapping means for gamut mapping the color image data for the object image into the gamut of the output device using the matrix coefficients.
Claim 10
Dependent Claim
91 words
A color image processing apparatus for gamut mapping color image data for an object image into a gamut of an output device, comprising: inputting means for inputting color image data for the object image; detecting means for detecting a color distribution of the color image data for the object image; calculating means for calculating matrix coefficients using the color distribution detected by said detecting means; and gamut mapping means for gamut mapping the color image data for the object image into the gamut of the output device using the matrix coefficients.
Claim 11
Dependent Claim
57 words
The apparatus according to claim 7, further comprising transforming means for transforming the color image data for the object image into color image signals on a uniform color space, wherein said gamut mapping means uses the color image signals to gamut map the color image data for the object image into the gamut of the output device.
Claim 12
Dependent Claim
36 words
The apparatus according to claim 7, wherein said gamut mapping means performs gamut mapping on the color image data for the object image so that the object image fits inside the gamut of the output device.
Claim 13
Dependent Claim
81 words
A color image processing method for gamut mapping color image data for an object image into a gamut of an output device, comprising the steps of: inputting color image data for the object image; detecting a color distribution of the color image data for the object image; calculating matrix coefficients using the color distribution detected in said detecting step; and gamut mapping the color image data for the object image into the gamut of the output device using the matrix coefficients.
Claim 14
Dependent Claim
81 words
A color image processing method for gamut mapping color image data for an object image into a gamut of an output device, comprising the steps of: inputting color image data for the object image; detecting a color distribution of the color image data for the object image; calculating matrix coefficients using the color distribution detected in said detecting step; and gamut mapping the color image data for the object image into the gamut of the output device using the matrix coefficients.
Claim 15
Dependent Claim
59 words
The apparatus according to claim 1, wherein said second generating means includes correcting means for correcting the difference data prior to generating the correction data, and wherein said gamut mapping means includes adding means for adding the correction data to the color image data in order to map the color image data into the gamut of the output device.
Claim 16
Dependent Claim
33 words
The apparatus according to claim 7, wherein the output device comprises an image forming means, and wherein said calculating means calculates the matrix coefficients based on a gamut of the image forming means.
Claim 17
Dependent Claim
112 words
A color image processing apparatus comprising: calculating means for calculating matrix coefficients for mapping color image data for an input image into a color gamut of an image forming means using first information which defines a color gamut of the input image, and second information which defines the color gamut of the image forming means; color gamut mapping means for mapping the color image data for the input image into the color gamut of the image forming means by performing matrix calculations on the color image data using the matrix coefficients; and outputting means for outputting the color image data mapped by said color gamut mapping means to the image forming means.
Claim 18
Dependent Claim
112 words
A color image processing apparatus comprising: calculating means for calculating matrix coefficients for mapping color image data for an input image into a color gamut of an image forming means using first information which defines a color gamut of the input image, and second information which defines the color gamut of the image forming means; color gamut mapping means for mapping the color image data for the input image into the color gamut of the image forming means by performing matrix calculations on the color image data using the matrix coefficients; and outputting means for outputting the color image data mapped by said color gamut mapping means to the image forming means.
Claim 19
Dependent Claim
34 words
The apparatus according to claim 13, wherein said calculating means calculates the matrix coefficients using first and second information comprised of color image data having hues of R, G, B, C, M, and Y.
Claim 20
Dependent Claim
25 words
The apparatus according to claim 13, wherein said calculating means calculates the matrix coefficients for mapping color image data comprising R, G, and B data.
Claim 21
Dependent Claim
102 words
A color image processing method comprising the steps of: calculating matrix coefficients for mapping color image data for an input image into a color gamut of an image forming means using first information which defines a color gamut of the input image, and second information which defines the color gamut of the image forming means; mapping the color image data for the input image into the color gamut of the image forming means by performing matrix calculations on the color image data using the matrix coefficients; and outputting the color image data mapped in said mapping step to the image forming means.
Claim 22
Dependent Claim
102 words
A color image processing method comprising the steps of: calculating matrix coefficients for mapping color image data for an input image into a color gamut of an image forming means using first information which defines a color gamut of the input image, and second information which defines the color gamut of the image forming means; mapping the color image data for the input image into the color gamut of the image forming means by performing matrix calculations on the color image data using the matrix coefficients; and outputting the color image data mapped in said mapping step to the image forming means.
Claim 23
Dependent Claim
93 words
A color image processing apparatus comprising: inputting means for inputting color image data for an object image; outputting means for outputting high-saturation data for a plurality of hues in the color image data for the object image, the high-saturation data corresponding to a color gamut of the color image data for the object image; and color gamut mapping means for mapping the color image data for the object image into a color gamut of an image outputting means using a parameter which is based on the high-saturation data for the plurality of hues.
Claim 24
Dependent Claim
93 words
A color image processing apparatus comprising: inputting means for inputting color image data for an object image; outputting means for outputting high-saturation data for a plurality of hues in the color image data for the object image, the high-saturation data corresponding to a color gamut of the color image data for the object image; and color gamut mapping means for mapping the color image data for the object image into a color gamut of an image outputting means using a parameter which is based on the high-saturation data for the plurality of hues.
Claim 25
Dependent Claim
26 words
The apparatus according to claim 17, wherein said outputting means outputs high-saturation data for the plurality of hues comprising R, G, B, C, M, and Y.
Claim 26
Dependent Claim
21 words
The apparatus according to claim 17, wherein said color gamut mapping means maps the color image data by using matrix coefficients.
Claim 27
Dependent Claim
21 words
The apparatus according to claim 17, wherein said inputting means inputs color image data comprised of R, G, and B data.
Claim 28
Dependent Claim
116 words
A color image processing method comprising the steps of: inputting color image data for an object image; gamut mapping the color image data for the object image into a color gamut of an image output means based on high-saturation colors in each of a plurality of hues in the color image data for the object image; and outputting the color image data mapped in said gamut mapping step to the image output means; wherein said gamut mapping step performs gamut mapping so that the high-saturation colors in each of the plurality of hues in the color image data for the object image are converted into high-saturation colors for the color gamut of the image output means.
Claim 29
Dependent Claim
116 words
A color image processing method comprising the steps of: inputting color image data for an object image; gamut mapping the color image data for the object image into a color gamut of an image output means based on high-saturation colors in each of a plurality of hues in the color image data for the object image; and outputting the color image data mapped in said gamut mapping step to the image output means; wherein said gamut mapping step performs gamut mapping so that the high-saturation colors in each of the plurality of hues in the color image data for the object image are converted into high-saturation colors for the color gamut of the image output means.
Claim 30
Dependent Claim
38 words
The method according to claim 21, wherein said gamut mapping step performs gamut mapping on the color image data for the object image so that the object image fits inside of the gamut of the image output means.
Claim 31
Dependent Claim
54 words
The method according to claim 21, wherein said gamut mapping step maps the color image data for the object image so that the high-saturation colors in each of the plurality of hues in the color image data for the object image comprise high-saturation colors for representing the color gamut of the image output means.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-08-11 | 2001-02-10 | 2001-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-08-11 | 2005-02-10 | 2005-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-08-11 | 2009-02-10 | 2009-08-12 | $7700.00 | Window Closed / Lapsed |