RICE PARAMETER INITIALIZATION FOR COEFFICIENT LEVEL CODING IN VIDEO CODING PROCESS

摘要

Techniques are described for initializing a Rice parameter used to define codes for coefficient level coding. According to the techniques, the initial value of the Rice parameter is determined for a coefficient group (CG) in a transform block of video data based on statistics of coefficient levels that are gathered for previously coded coefficients of the video data. The statistics may be statistics of absolute values of coefficient levels or remaining absolute values of coefficient levels of previously coded coefficients. A value of the statistics may be initialized to zero at a beginning of a video slice and updated based on coefficient levels coded in each CG of the slice. The statistics may be updated once per CG. In some cases, statistics may be gathered separately for each of a plurality of different categories of CGs that are defined based on characteristics of transform blocks that include the CGs.