Image processing apparatus for preparing printing plates having

Abstract

According to this invention, the original cassette accommdates the color originals having difference sizes The original cassette is mounted on an original board. Plane scanning is carried out without causing flare by use of an image sensor in accordance with a transmissive method or a reflective method. Auxiliary scanning is then effected after executing a linear reading process, thereby obtaining image data of the whole. Printing plates of CMY and black (K) are directly outputted. Processing is performed by executing rough prescanning and fine main scanning when reading the image. The conditional parameters for processing the images are automatically (or manually) set based on the data stored. The images can be outputted at a high efficiency from a relation between the original and the photosensitive material. The image processing system of this invention has a function to indicate a speed preference mode, a photosensitive material consumption preference mode an a quality preference mode. When indicating the speed preference mode, an output pattern having the least number of scannings is selected. When indicating the photosensitive material consumption preference mode, there is selected an output pattern in which the top end of the printing plate to be outputted is the closest to the output original point. In the case or indicating the quality preference mode, the quality of the output image is enhanced by increasing the read resolution in the input unit. In this case, the optical magnifications are calculated, wherein the short and long sides of the original reading range undergo the main scanning.