This example shows an image with a portion greatly enlarged, in which the individual pixels are rendered as small squares and can easily be seen.
A photograph of sub-pixel display elements on a laptop's LCD screen
In digital imaging, a pixel, pel,[1] dots, orpicture element[2] is a physical point in araster image, or the smallest addressable element in an all points addressable display device; so it is the smallest controllable element of a picture represented on the screen. The address of a pixel corresponds to its physical coordinates. LCD pixels are manufactured in a two-dimensional grid, and are often represented using dots or squares, but CRT pixels correspond to their timing mechanisms .
Each pixel is a sample of an original image; more samples typically provide more accurate representations of the original. The intensityof each pixel is variable. In color imaging systems, a color is typically represented by three or four component intensities such asred, green, and blue, or cyan, magenta, yellow, and black.
In some contexts (such as descriptions ofcamera sensors), the term pixel is used to refer to a single scalar element of a multi-component representation (more precisely called a photosite in the camera sensor context, although the neologism sensel is sometimes used to describe the elements of a digital camera's sensor),[3] while in yet other contexts the term may be used to refer to the set of component intensities for a spatial position. Drawing a distinction between pixels, photosites, and samples may reduce confusion when describing color systems that use chroma subsampling or cameras that useBayer filter to produce color components via upsampling.
The word pixel is based on a contraction ofpix (from word "pictures", where it is shortened to "pics", and "cs" in "pics" sounds like "x") and el (for "element"); similar formations with 'el' include the words voxel[4]and texel.[4]
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