  Chroma from luma (CfL) prediction is a new and promising chroma-only intra
predictor that models chroma pixels as a linear function of the coincident
reconstructed luma pixels. In this paper, we present the CfL predictor adopted
in Alliance Video 1 (AV1), a royalty-free video codec developed by the Alliance
for Open Media (AOM). The proposed CfL distinguishes itself from prior art not
only by reducing decoder complexity, but also by producing more accurate
predictions. On average, CfL reduces the BD-rate, when measured with CIEDE2000,
by 5% for still images and 2% for video sequences.
