EP0494034A2
Expired / Lapsed
EP
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Automatic correction for color printing
Assignee: International Business Machines Corp
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Filing: 1991-11-29
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Granted: —
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Expires: 2011-11-29
Abstract
Abstract Automatic processing of color signals to print an accurate reproduction of an original color image. The RGB scan signals are processed to use the full dynamic range of the system and to adjust the values such that the gray scale lines of the color components pass through the white points. The additive color signals are converted to subtractive color signals that are adjusted so that the gray scale lines pass through the black points to produce auto-matically an accurate reproduction with a proper neutral gray scale. The processing is arranged to make the adjustments and corrections as fast as possible
Inventors
- 👤 Anthony Joseph Dattilo
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 19:21
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/46; H04N1/56; H04N1/60; H04N1/603; H04N1/6027
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
100 words
A method of processing color component signals for accurate color image reproduction comprising the steps of: scanning a color image to be reproduced to derive color compo-nent signals of the color image; adjusting the color component signals to correct for errors in the signals introduced by the scanning step; converting said color component signals to color printing signals; correcting automatically the color printing signals for nonlinearities in reproduction characteristics due to the inks used to make the reproduction; and printing a color reproduction of the color image to be reproduced according to the values of the corrected color printing signals.
Claim 2
Dependent Claim
27 words
The method claimed in claim 1 wherein said color component signals represent the values of red, green, and blue hues in the color image to be reproduced.
Claim 3
Dependent Claim
29 words
The method claimed in claim 1 wherein the adjusting step includes corrections to errors in dynamic ranges and gamma functions of the color component signals from the scanning step.
Claim 4
Dependent Claim
31 words
The method claimed in claim 1 wherein said converting step includes the steps of: scanning samples of inks to be used in the printing step;and deriving coefficients representing color conversion factors.
Claim 5
Dependent Claim
19 words
The method claimed in claim 1 wherein the color printing signals represent cyan, magenta, and yellow color ink values.
References Cited (Backward Citations)
No citation records indexed.
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