METHODS AND SYSTEMS TO ESTIMATE MOTION BASED ON RECONSTRUCTED REFERENCE FRAMES AT A VIDEO DECODER

摘要

Methods and systems to apply motion estimation (ME) based on reconstructed reference pictures in a B frame or in a P frame at a video decoder. For a P frame, projective ME may be performed to obtain a motion vector (MV) for a current input block. In a B frame, both projective ME and mirror ME may be performed to obtain an MV for the current input block. The ME process can be performed on sub-partitions of the input block, which may reduce the prediction error without increasing the amount of MV information in the bitstream. Decoder-side ME can be applied for the prediction of existing inter frame coding modes, and traditional ME or the decoder-side ME can be adaptively selected to predict a coding mode based on a rate distribution optimization (RDO) criterion.

主权项

1. A machine-implemented method, comprising:
defining a motion estimation search window for a first block of a first frame of a video; selecting a motion vector to a block of a second frame of the video and a motion vector to a block of a third frame of the video based on the search window, distances between the first frame and each of the second and third frames, and a measure of visual similarity between the respective blocks of the second and third frames; and deriving a motion vector for the first block based on one or more of the selected motion vector to a block to the second frame and the selected motion vector to a block of the third frame.