Chrominance
What is chrominance?
Chroma or chrominance in video systems is a signal which conveys information about the color of the video. Chroma is the difference between the two color components. In composite video signals, chroma is a modulated sub-carrier signal. The phase represents the saturation and the amplitude represents hue.
What are the different chroma standards?
Chrominance is encoded into the video signal. The PAL system uses a frequency of 4.43MHz over the video signal. NTSC uses a frequency of 3.58 MHz more than the video signal. The presence of color-burst on the back porch is an indication of the presence of chrominance.
What is chroma sub-sampling?
Chroma sampling is the encoding of images by using less resolution for chroma than luminance. It takes advantage of human vision which can detect a difference in luminance more than chrominance. It is used in the encoding of videos and JPEG.