From picture element. In digital imaging the term pixel frequently refers to the smallest complete discrete element that makes up an image. A dot.
While this may sound like a fairly straightforward definition, in reality things are very much contextual. For example, in colour imaging the concept of subpixels comes into play. On an LCD screen, say, what appears as a single white dot actually consists of three subpixels - one blue, one red, one green. Similarly most digital camera image sensors record brightness at each pixel but colour is recorded in a mosaic fashion across groups of four pixels.
The more pixels there are in a digital image, all other things being equal, the higher quality the image, though this is affected as well by bit depth and pixel density.
cf. bit depth, dpi, effective megapixels, image sensor, megapixel, pixel density.
Entry last updated 2002-04-04. Term 927 of 1487.
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