Interpolation (spatial)

Defining the value of a new pixel from those of its near neighbors. For example, when re-positioning or re-sizing a digital image, for dramatic effect or to change picture format, more, fewer or different pixels are required from those in the original image. Simply repeating or removing pixels causes unwanted artifacts. For far better results the new pixels have to be interpolated, calculated by making suitably weighted averages of adjacent input pixels, to produce a more accurate result. The quality will depend on the techniques used; bi-cubic interpolation is generally accepted as being good, and the number of pixels (points) taken into account (hence 16-point interpolation), or area of original picture that is used to calculate the result all affect the quality of the result.

See also: Anti-aliasing, Interpolation (temporal), Sub-pixel