Facsimile and static presentation processing – Facsimile – Specific signal processing circuitry
Patent
1990-07-19
1992-07-28
Ng, Jin F.
Facsimile and static presentation processing
Facsimile
Specific signal processing circuitry
358448, 358463, H04N 140
Patent
active
051345030
ABSTRACT:
The image processing apparatus of the present invention determines the number of surrounding pixels to be averaged and their locations, determines a weighting coefficient based on the density and contrast levels of an input image data derived from a continuous tone image, and performs an averaging operation on the input image signal by performing a weighting operation using the averaged result of the surrounding pixels, the input image data, and the weighting coefficient. Therefore, the image processing apparatus of the present invention is capable of reducing the noise level over a wide range of image types, from shadow regions with high density. Further to highlight regions with low density, and images reproduced by this apparatus do not exhibit a deterioration of the sharpness of image boundaries in the high density regions, images characterized by a gradual change in the density level do not turn out having an unnatural quality.
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Fuji Photo Film Co. , Ltd.
Lefkowitz Edward
Ng Jin F.
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