Editing Pixel (section)

===Sampling patterns===
For convenience, pixels are normally arranged in a [[regular grid|regular two-dimensional grid]]. By using this arrangement, many common operations can be implemented by uniformly applying the same operation to each pixel independently. Other arrangements of pixels are possible, with some sampling patterns even changing the shape (or [[Convolution kernel|kernel]]) of each pixel across the image. For this reason, care must be taken when acquiring an image on one device and displaying it on another, or when converting image data from one pixel format to another.

For example:
[[Image:Wikipedia ClearType.png|thumb|right|upright=1.15|Text rendered using [[ClearType]] using subpixels]]
* [[Liquid crystal display|LCD screens]] typically use a staggered grid, where the red, green, and blue components are sampled at slightly different locations.  [[Subpixel rendering]] is a technology which takes advantage of these differences to improve the rendering of text on LCD screens.
* The vast majority of color digital cameras use a [[Bayer filter]], resulting in a regular grid of pixels where the ''color'' of each pixel depends on its position on the grid.
* A [[clipmap]] uses a hierarchical sampling pattern, where the size of the [[support (mathematics)|support]] of each pixel depends on its location within the hierarchy.
* Warped grids are used when the underlying geometry is non-planar, such as images of the earth from space.<ref>{{cite web|url=http://staff.utia.cas.cz/zitova/registration.htm|title=Image registration of blurred satellite images|publisher=staff.utia.cas.cz|date=28 February 2001|access-date=2008-05-09|url-status=live|archive-url=https://web.archive.org/web/20080620023947/http://staff.utia.cas.cz/zitova/registration.htm|archive-date=20 June 2008}}</ref>
* The use of non-uniform grids is an active research area, attempting to bypass the traditional [[Nyquist rate|Nyquist limit]].<ref>{{cite journal |title= Image representation by a new optimal non-uniform morphological sampling | doi=10.1016/S0031-3203(99)00158-2 |volume=33 |issue=6 |journal=Pattern Recognition |pages=961–977|year= 2000 |last1= Saryazdi |first1= Saeı̈d |last2= Haese-Coat |first2= Véronique |last3= Ronsin |first3= Joseph | bibcode=2000PatRe..33..961S }}</ref>
* Pixels on computer monitors are normally "square" (that is, have equal horizontal and vertical sampling pitch); pixels in other systems are often "rectangular" (that is, have unequal horizontal and vertical sampling pitch – oblong in shape), as are [[digital video]] formats with diverse [[Pixel aspect ratio|aspect ratios]], such as the [[anamorphic widescreen]] formats of the [[Rec. 601]] digital video standard.