Resolution-based context selection for vector difference coding

Abstract

A decoder receives, from a video bitstream, a first indication of a resolution of a vector difference for a block. Based on the first indication and a position of a magnitude symbol in a suffix portion of a codeword representing the vector difference to be decoded, a probability model is selected from a plurality of probability models for the magnitude symbol. The decoder arithmetically decodes, from the video bitstream and based on the probability model, a second indication indicating whether the magnitude symbol of the vector difference is equal to a corresponding magnitude symbol of a vector difference predictor. A value of the magnitude symbol of the vector difference is determined based on the second indication and a value of the corresponding magnitude symbol of the vector difference predictor. The block is decoded based on the vector difference represented by the codeword having the magnitude symbol with the determined value.