Image Chroma Subsampling Detector
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Chroma Subsampling
Chroma subsampling is a method used to encode images by implementing less resolution for color information than for black/white information. A common subsampling type used for videos is 4:2:0.
Why do we test it?
Chroma subsampling takes advantage of the human's visual system's lower acuity for color differences than for black/white. Savely removing information that we can't notice saves bytes, resulting in lower file sizes.