 Luma (brightness, resolution) is stored separately from chroma (color, hue, phase) and even further separated into red and blue components.The chroma is also subsampled to , meaning it is reduced to half resolution vertically and half resolution horizontally, i.e., to just one quarter the number of samples used for the luma component of the video.This use of higher resolution for some color components is similar in concept to the Bayer pattern filter that is commonly used for the image capturing sensor in digital color cameras.