The role and characteristics of Postscript

It is necessary to understand Postscript before introducing RIP. Here, take Adobe Postscript3 as an example for a brief introduction, in order to have a comprehensive understanding of it.
Adobe Postscript3 is a major page description language and is the dominant workflow model in the printing and publishing process. The appearance of Postscript3 makes the color change smoother and has a better reproduction of gradation. Adobe Postscript3 supports high-fidelity color and is combined with the latest PDF (portable document format) version. A few years ago, Adobe introduced Acrobat software and PDF file formats. In recent years, the PDF format has had a great influence on digital presses.
Postscript RIP work can be divided into two phases: First, it creates a display list of all text, graphics, images, and background elements. It then converts each element into a bitmap, or in a multicolored document, forms a color separation bitmap for each color. When a file is distilled into a PDF file, the program has performed half of the postscript rasterization process. The PDF file is actually a display list generated during the first step of the RIP process.
The latest PDF3 version expands the editability of PDF files and supports some color management and professional copying techniques such as FM screening and high-fidelity color. Another important improvement is the independence of the page: Each page in the PDF file can be treated as a separate element. This simplifies the process of printing, network delivery, and grouping. Moreover, PDF and Postscript3 make the raster image processing more productive and greatly improve the flexibility of the prepress production system. Instead of having to send a single large-format design file with a high-resolution image to RIP, PDF first reduces the file size and then turns it into its own page element. Compared with the past, the current process appears to have more advantages.