YUVkoodaukseen

YUVkoodaus refers to a family of color spaces used in video and image processing. YUV is a digital representation of the Y'CbCr color space, which itself is derived from the analog YIQ color space used in early NTSC television systems. The YUV system separates color information into two components: luminance (Y) and chrominance (UV). The luminance component represents the brightness or grayscale information of an image, while the chrominance components (U and V) represent the color information, specifically the blue and red components of the color, respectively.

The primary advantage of YUV (and its related spaces like Y'CbCr) is its ability to reduce the amount of data required to represent an image or video without significant perceptual loss. This is achieved through subsampling, where the chrominance information is sampled at a lower resolution than the luminance information. Human vision is more sensitive to changes in brightness than to changes in color. Therefore, reducing the spatial resolution of the color components has a less noticeable impact on perceived image quality compared to reducing the resolution of the luminance component. Common subsampling schemes include 4:4:4 (no subsampling), 4:2:2 (luminance sampled at full resolution, chrominance sampled horizontally at half resolution), and 4:2:0 (luminance sampled at full resolution, chrominance sampled horizontally and vertically at half resolution). YUVkoodaus is widely used in video compression standards such as MPEG and H.264, as well as in broadcast television formats.