  Banding artifacts are artificially-introduced contours arising from the
quantization of a smooth region in a video. Despite the advent of recent higher
quality video systems with more efficient codecs, these artifacts remain
conspicuous, especially on larger displays. In this work, a comprehensive
subjective study is performed to understand the dependence of the banding
visibility on encoding parameters and dithering. We subsequently develop a
simple and intuitive no-reference banding index called CAMBI (Contrast-aware
Multiscale Banding Index) which uses insights from Contrast Sensitivity
Function in the Human Visual System to predict banding visibility. CAMBI
correlates well with subjective perception of banding while using only a few
visually-motivated hyperparameters.
