METHOD AND APPARATUS FOR VIDEO CODING WITH AUTOMATIC MOTION INFORMATION REFINEMENT

摘要

In a particular implementation, a video decoder may refine an initial motion vector predictor decoded from the bitstream for a current block. In order to reduce signaling overhead, the decoder may determine whether or not motion refinement is used based on information that is already available, for example, based on whether the motion field is uniform around the current block, and whether there is a certain level of textureness in adjacent blocks. The motion vector difference decoded from the bitstream can be used to automatically activate or deactivate the motion refinement without receiving explicit signaling in the bitstream. For example, when the motion vector difference is smaller than a threshold, motion refinement is automatically activated, and when the motion vector difference is greater than another threshold, motion refinement is automatically deactivated. A corresponding video encoder may choose whether to use and signal motion refinement based on encoder decisions.