::Raster graphics


Image::graphics    Raster::raster    Color::title    Graphics::pixel    Pixels::formats    November::display

The smiley face in the top left corner is a raster image. When enlarged, individual pixels appear as squares. Zooming in further, they can be analyzed, with their colors constructed by adding the values for red, green and blue.

In computer graphics, a raster graphics image is a dot matrix data structure representing a generally rectangular grid of pixels, or points of color, viewable via a monitor, paper, or other display medium. Raster images are stored in image files with varying formats.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>{{ safesubst:#invoke:Unsubst||$N=Self-published inline |date=__DATE__ |$B= {{#invoke:Category handler|main}}[self-published source?] }}

A bitmap, a single-bit raster,<ref>James D. Foley (1995). Computer Graphics: Principles and Practice. Addison-Wesley Professional. p. 13. ISBN 0-201-84840-6. "The term bitmap, strictly speaking, applies only to 1-bit-per-pixel bilevel systems; for multiple-bit-per-pixel systems, we use the more general term pixmap (short for pixel map)."</ref> corresponds bit-for-bit with an image displayed on a screen, generally in the same format used for storage in the display's video memory, or maybe as a device-independent bitmap. A raster is technically characterized by the width and height of the image in pixels and by the number of bits per pixel (a color depth, which determines the number of colors it can represent).<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

The printing and prepress industries know raster graphics as contones (from "continuous tones"). The opposite to contones is "line work", usually implemented as vector graphics in digital systems.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref>

Raster graphics sections
Intro  Etymology  Applications  Resolution  Raster-based image editors  See also  References  External links  

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