US 5,398,124 A · Image processor

Abstract

In an image possessor, two kinds of color differences in the orthogonal coordinate axes in the hue plane in the color space are separated from the digital data of three primary colors, and the separate color signals are synthesized to generate the chroma signal. When the digital data of the three primary colors are converted to the data of the reproduction colors with use of the under color remove amount and the black paint amount, an under color remove amount is subtracted from the digital data of the three primary colors, while a black paint amount which is the black data obtained from the digital data is generated to print with black toners. The under color remove amount and the black paint amount are increased with increase in the chroma signal according to the color data of the three primary colors and the chroma signal at the same pixel position. The edge emphasis is performed not on the image data of the three primary colors in the subtractive color system, but on the image data of the black color, in an edge image portion of achromatic color. Further, in the edge emphasis, a first change in the value signal and a second change in the image data for image reproduction are detected, and the two changes are synthesized. Then, the edge emphasis is conducted on the image data for printing or on the image data for color reproduction according to the synthesized change.

Claims12

Dependent claims

An image processor, wherein each image data is processed to obtain image data for printing for each pixel, comprising:

a read means for reading a document image to send an image data of three primary colors of an additive color system;
an edge decision means for deciding an edge image portion according to the image data received from said read means;
an achromatic color decision means for deciding an achromatic color according to the image data received from said read means;
a generation means for generating image data of three primary colors in a subtractive color system and of a black color from the image data received from said read means;
a correction means for conducting edge emphasis processing not on the image data of the three primary colors in the subtractive color system, but on the image data of the black color, in an edge image portion of achromatic color decided by said edge decision means and said achromatic color decision means.

2 more elements

Dependencies are inferred from the claim text.

Image processor

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Image processor

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Abstract

Claims12