ENTROPY CODING OF MOTION VECTOR DIFFERENCES

摘要

A decoder for decoding a video from a datastream in which horizontal and vertical components of motion vector difference values are coded using binarizations of horizontal and vertical components is described, where the binarizations are the first interval in the domain of horizontal and vertical components below the truncation value. Within, a truncated unary code of the horizontal and vertical components, respectively, and a prefix in the form of a truncated unary code for each truncated value, within the second interval of the domain of the horizontal and vertical components above the truncated value, Identify the combination of arcs and suffixes in the form of exponential-Golomb codes of horizontal and vertical components. The entropy encoder performs context-adaptive binary entropy decoding with exactly one context per position of the truncated unary code, typical for horizontal and vertical components of motion vector difference values, for the horizontal and vertical components of motion vector difference values. It is configured to derive a truncated unary code from the used data stream and an exponential-Golomb code using a constant equal-probability bypass scheme to obtain binarization of motion vector difference values. The desymbalizer is configured to debinarize the binarizations of the motion vector difference syntax elements to obtain an integer value of the horizontal and vertical components of the motion vector difference values. The reconstructor is configured to reconstruct the video based on the integer values of the horizontal and vertical components of the motion vector difference values.