Content adaptive motion compensation filtering for high efficiency video coding

摘要

A system and method for adaptive motion filtering to improve subpel motion prediction efficiency of interframe motion compensated video coding is described. The technique uses a codebook approach that is efficient in search complexity to look-up best motion filter set from a pre-calculated codebook of motion filter coefficient set. In some embodiments, the search complexity is further reduced by partitioning the complete codebook into a small base codebook and a larger virtual codebook, such that the main calculations for search only need to be performed on the base codebook.

主权项

1. A video-decoder-device-implemented method for predicting blocks of an encoded video frame, the method comprising:
obtaining, by the video decoder device, a codebook comprising a multiplicity of motion-compensation filters grouped into a plurality of subpel-position groups that respectively correspond to a plurality of subpel positions, each of the plurality of subpel-position groups comprising a plurality of motion-compensation filters suitable for interpolating blocks of the encoded video frame at a corresponding one of the plurality of subpel positions; obtaining an encoded bitstream comprising the encoded video frame and a subpel-filter code identifying an adaptive motion-compensation filter set within the codebook, the adaptive motion-compensation filter set comprising the plurality of motion-compensation filters respectively corresponding to the plurality of subpel positions; during decoding of the encoded video frame, the video decoder device selecting from the codebook the adaptive motion-compensation filter set identified by the subpel-filter code; using the adaptive motion-compensation filter set identified by the subpel-filter code, predicting a plurality of blocks of the encoded video frame; generating a decoded picture according to at least the predicted plurality of blocks of the encoded video frame; and rendering the generated decoded picture to a display associated with the video decoder device.