Patent ID: 7375853

Claim:
An image processing apparatus, comprising: image reading means for reading analog color image data of a color image, separating the analog color image data into red image data, green image data, and blue image data, and converting the red image data into digital red image data, the green image data into digital green image data, and the blue image data into digital blue image data; and processing means for subjecting the digital red image data, the digital green image data, and the digital blue image data to digital processing, wherein the processing means includes color identifying means for determining, for each of the digital red image data, the digital green image data, and the digital blue image data, whether there exists black data, generating density data from the black data when black data exists, and generating color data from data other than the black data; multinarizing means for converting the color data for each of the digital red image data, the digital green image data, and the digital blue image data into multinary color data; magnification varying means for varying the density data and the multinary color data, using a cubic function convolution method; binarizing means for binarizing the varied multinary color data, based on a predetermined threshold; and image printing means for printing the binarized varied multinary color data and the varied density data, onto a recording medium.