Chroma subsampling
![In full size, this image shows the difference between four subsampling schemes. Note how similar the color images appear. The lower row shows the resolution of the color information.](/Images/godic/202501/05/Colorcomp0259.jpg")
Chroma subsampling is the practice of encoding images by implementing less resolution for chroma information than for luma information, taking advantage of the human visual system's lower acuity for color differences than for luminance.
It is used in many video encoding schemes — both analog and digital — and also in JPEG encoding.