Adaptive selection of picture-level quantization parameters for predicted video pictures

摘要

Techniques and tools for adaptive selection of picture quantization parameters (“QPs”) for predicted pictures are described. For example, a video encoder adaptively selects a delta QP for a B-picture based on spatial complexity, temporal complexity, whether differential quantization is active, whether the B-picture is available as a reference picture, or some combination or subset of these or other factors. The delta QP can then be used to adjust the picture QP for the B-picture (e.g., to reduce bit rate for the B-picture without appreciably reducing the perceived quality of a video sequence.