Facsimile and static presentation processing – Natural color facsimile – Color correction
Patent
1995-05-10
1998-01-20
Rogers, Scott A.
Facsimile and static presentation processing
Natural color facsimile
Color correction
358520, 358523, 358504, 382167, G03F 308, H04N 146
Patent
active
057106444
ABSTRACT:
In a color expression method and an image processing apparatus using that method, characteristics of human vision which responds in proportion of a cube root of a luminance signal indicated by CIE L*a*b* colorimetric system is utilized. In look-up tables (for example), a cube-root (or other) conversion is performed and a difference signal of data on which the conversion has been performed is generated in subtraction circuits 104, 105. That is, 8-bit data for R, G, B are reduced to 7-bit data in the look-up tables, and each of two color signals after a subtraction operation is requantized to 6-bit data. Accordingly, color signals of 24 bits/pixel can be reduced to 19 bits/pixel, thus resulting in elimination of color data redundancy.
REFERENCES:
patent: 4409614 (1983-10-01), Eichler et al.
patent: 4500919 (1985-02-01), Schreiber
patent: 4751535 (1988-06-01), Myers
patent: 4769718 (1988-09-01), Imamura
patent: 4941038 (1990-07-01), Walowit
patent: 4965663 (1990-10-01), Sasaki
patent: 5126838 (1992-06-01), Ohsawa
patent: 5299291 (1994-03-01), Ruetz
patent: 5422739 (1995-06-01), Usami et al.
McColl et al., "Compression of Colour Image Data using Histogram Analysis and Clustering Techniques", Electronics and Communications Engineering, No. 1, 99. 93-100 (1989).
Roger et al., "Nutzungstiefe eines Videosystems", Elektronik, No. 7, pp. 84-88 (Jul. 1992).
Green et al., "Colour Error Reduction in Video Systems, IEEE Transactions on Broadcasting", No. 1, pp. 99-107 (Mar. 1990).
Mikami et al., "Full Color Image Printer", Fujitsu Scientific & Technical Journal, Summer, No. 2, pp. 166-174 (1988).
Sugiura et al., "The Color Space for Multi-Bender Communication", Journal of the Institute of Image Electronics Engineers of Japan, vol. 22, No. 1, 1993, pp. 11-19.
Canon Kabushiki Kaisha
Lee Thomas D.
Rogers Scott A.
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