Skip thresholding in pipelined video encoders

Abstract

The video encoders described herein may make an initial determination to designate a macroblock as a skip macroblock, but may subsequently reverse that decision based on additional information. For example, an initial skip mode decision may be based on aggregate distortion metrics for the luma component of the macroblock (e.g., SAD, SATD, or SSD), then reversed based on an individual pixel difference metric, an aggregate or individual pixel metric for a chroma component of the macroblock, or on the position of the macroblock within a macroblock row. The final skip mode decision may be based, at least in part, on the maximum difference between any pixel in the macroblock (or in a region of interest within the macroblock) and the corresponding pixel in a reference frame. The initial skip mode decision may be made during an early stage of a pipelined video encoding process and reversed in a later stage.