This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Raster image processor" – news ·newspapers ·books ·scholar ·JSTOR(January 2023) (Learn how and when to remove this message)

Araster image processor (RIP) is a component used in aprinting system which produces araster image also known as abitmap.^[1][2] Such a bitmap is used by a later stage of the printing system to produce the printed output.^[3] The input may be a page description in a high-levelpage description language such asPostScript,PDF, orXPS, includingraster and/orvector graphics.^[4] The input can also be or include bitmaps of higher or lower resolution than the output device, which the RIP resizes using animage scaling algorithm.

Originally a RIP was arack of electronic hardware which received the page description via some interface (e.g.RS-232) and generated a "hardware bitmap output" which was used to enable or disable eachpixel on a real-time output device such as alaser printer, an opticalfilm recorder,computer to film, orcomputer to plate.

A RIP can be implemented as a software module on a general-purpose computer, or as afirmware program executed on amicroprocessor inside a printer. For high-end typesetting, standalone hardware RIPs are sometimes used.Ghostscript, GhostPCL, and ColorBurst's Overdrive (formacOS) are examples of software RIPs. Every PostScript printer contains a RIP in itsfirmware. The RIPchip in alaser printer sends itsraster image output to thelaser.

Earlier RIPs retained backward compatibility withphototypesetters/photosetters, so they supported the older languages. So, for example, Linotype RIPs supported CORA (RIP30).

1. Interpretation: This is the stage where the supported PDLs (page description languages) are translated into a private internal representation of each page. Most RIPs process pages serially, one page at a time, so the current machine state is only for the current page. After a page has been output, the page state is discarded to prepare for the next page.
2. Rendering: A process through which the private internal representation is turned into acontinuous-tone bitmap. In practical RIPs, interpretation and rendering are frequently done together. Simple languages were designed to work on minimal hardware, so tend to "directly drive" the renderer.
3. Screening: In order to print, the continuous-tone image is converted into ahalftone (pattern of dots). Two screening methods or types areamplitude modulation (AM) screening andstochastic orfrequency modulation (FM) screening. In AM screening, dot size varies depending on object density—tonal values; dots are placed in a fixed grid. In FM screening, dot size remains constant and dots are placed in random order to create darker or lighter areas of the image; dot placement is precisely controlled by sophisticated mathematical algorithms.

• Image tracing (raster-to-vector "conversion")
• Laser printing
• Raster graphics
• Vector graphics

• Printing technology
• Printing terminology

• Articles with short description
• Short description is different from Wikidata
• Articles needing additional references from January 2023
• All articles needing additional references