Editing Core Image (section)

==Pixel accuracy==
All pixel processing provided by an Image Unit is performed in a pre-multiplied alpha ([[RGBA color space|RGBA]]) color space, storing four color channels: red, green, blue, and transparency ([[alpha channel|alpha]]). Each color channel is represented by a 32-bit, [[floating point]] number. This provides exceptional color depth, far greater than can be perceived by the [[human eye]], as each pixel is represented by a 128-bit vector (four 32-bit color channels). For color spaces of lower bit-depth, the floating-point calculation model employed by Core Image provides exceptional performance, which is useful when processing multiple images or video frames.<ref name="developer.apple.com"/><ref>{{cite web | title=Mac Dev Center - Core Image Programming Guide - Core Image Concepts - Color Components and Premultiplied Alpha | url=https://developer.apple.com/mac/library/documentation/GraphicsImaging/Conceptual/CoreImaging/ci_concepts/ci_concepts.html#//apple_ref/doc/uid/TP30001185-CH202-BCIDAIEJ | access-date=September 20, 2009}}</ref>