Sign prediction for block-based video coding

Abstract

Implementations of the disclosure provide a video decoding apparatus and method for transform coefficient sign prediction on a video decoder side. The method includes: receiving a bitstream including a sequence of sign signaling bits; determining a sign prediction area in a transform block of a video frame from a video for performing the sign prediction for the transform coefficients of the transform block; generating a plurality of candidate hypotheses for a set of candidate transform coefficients associated with the sign prediction area of the transform block; selecting a hypothesis from the plurality of candidate hypotheses as a set of predicted signs for the set of candidate transform coefficients based on a cost function; and estimating original signs for the set of candidate transform coefficients based on the set of predicted signs and the sequence of sign signaling bits.