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US5875260A Expired / Lapsed US ⏱️ 0.0 years remaining

Image processing apparatus and method for altering color image signals

Assignee: Canon Inc
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Filing: 1995-10-27
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Granted: 1999-02-23
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Expires: 2015-10-27
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Abstract

Abstract An input color signal is converted into a color signal representing a color which is visually closer to a color represented by the input color signal by performing gamut mapping processing based on the visual characteristics of humans. An image processing method includes the steps of inputting color signals, and performing gamut mapping processing in which the input color signal is converted into a color signal having a hue different from the hue of the input color signal based on a locus set corresponding to the hue and color saturation of the input color signal in color space.

Inventors

  • 👤 Kenichi Ohta

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 16:44
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/6058

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 82 words
A color image data processing method which performs color gamut mapping processing to color data, comprising the steps of: storing mapping parameters set for a plurality of representative colors; obtaining a mapping parameter corresponding to an input color from the stored mapping parameters based on the relation between a hue of the input color and a hue of the representative colors; and mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 2
Dependent Claim 82 words
A color image data processing method which performs color gamut mapping processing to color data, comprising the steps of: storing mapping parameters set for a plurality of representative colors; obtaining a mapping parameter corresponding to an input color from the stored mapping parameters based on the relation between a hue of the input color and a hue of the representative colors; and mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 3
Dependent Claim 11 words
A method according to claim 1, wherein the locus is non-linear.
Claim 4
Dependent Claim 18 words
A method according to claim 1, wherein the mapping parameter is obtained by interpolating the stored mapping parameters.
Claim 5
Dependent Claim 30 words
A method according to claim 1, wherein the mapping parameter is based on the hue and saturation of the color data, and is obtained by interpolating the stored mapping parameters.
Claim 6
Dependent Claim 20 words
A method according to claim 1, wherein the plurality of representative colors include R, G, B, C, M and Y.
Claim 7
Dependent Claim 28 words
A method according to claim 1, wherein color data outside of the color gamut is mapped at the boundary of the color data using the mapping parameter obtained.
Claim 8
Dependent Claim 78 words
A color image data processing device which performs color gamut mapping processing to color data, comprising: storing means for storing mapping parameters set for a plurality of representative colors; interpolating means for generating a mapping parameter based on the relation between a hue of an input color and a hue of the representative colors; and mapping means for mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 9
Dependent Claim 78 words
A color image data processing device which performs color gamut mapping processing to color data, comprising: storing means for storing mapping parameters set for a plurality of representative colors; interpolating means for generating a mapping parameter based on the relation between a hue of an input color and a hue of the representative colors; and mapping means for mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 10
Dependent Claim 88 words
A storage medium storing information for a color image data processing method which performs color gamut mapping processing to color data comprising the steps of: storing mapping parameters set for a plurality of representative colors; obtaining a mapping parameter corresponding to an input color from the stored mapping parameters based on the relation between a hue of the input color and a hue of the representative colors; and mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 11
Dependent Claim 88 words
A storage medium storing information for a color image data processing method which performs color gamut mapping processing to color data comprising the steps of: storing mapping parameters set for a plurality of representative colors; obtaining a mapping parameter corresponding to an input color from the stored mapping parameters based on the relation between a hue of the input color and a hue of the representative colors; and mapping the input color in a color gamut of an output device along a locus based on the mapping parameter.
Claim 12
Dependent Claim 12 words
A storage medium according to claim 8, wherein the locus is non-linear.
Claim 13
Dependent Claim 28 words
A storage medium according to claim 8, wherein the mapping parameter is based on the hue of the color data and obtained by interpolating the mapping parameters stored.

References Cited (Backward Citations)

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2002-02-22 2002-08-24 2003-02-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2006-02-22 2006-08-24 2007-02-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2010-02-22 2010-08-24 2011-02-23 $7700.00 Window Closed / Lapsed

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