The prepress system consists of color image input, image and text editing processing, graphic output and other parts. The prepress system workflow is as follows: 1. The image acquisition system collects image information. The pre-press system collects image information. The available devices include an image scanner, a digital camera, a video camera, etc., and an image scanner is commonly used. 2. The image processing system performs color separation, color correction, and the like on the acquired image. 3. Graphic drawing, text entry. Text can be entered via a computer keyboard, which is the most common method. Now, the prepress system can also obtain text in a variety of ways, such as handwriting input, voice output, and can also use OCR text recognition by scanning. 4. Graphic and text mixing. In the pre-press system special typesetting software or in the graphics software, image files, files and graphics are placed to form a complete printed page, and the size, size and position of the page, image, text and graphic are determined according to the final requirements. Five. Raster image processing. The image-mixed pages are interpreted by the raster image processor before output, and the dot information on the color layout surface is decomposed and the control information for controlling the exposure of the laser imagesetter is formed. 6. Output. Under the control of RIP, exposure and development treatment are carried out to obtain a color separation film for sunburn, or to directly output a printing plate.