Patent ID: 7602851

Claim:
A method of differential quantization in video coding of a coded video bit stream, comprising: analyzing motion vectors of macroblocks for a frame of a video sequence to determine whether global motion of the video at the frame in the video sequence is characteristic of panning or zooming; classifying regions of the frame according to perceptual significance based on the global motion determination; differentially quantizing the regions according to their perceptual significance classification in coding a compressed bit stream of the video sequence; signaling different quantization of the regions in the compressed bit stream, wherein the signaled different quantization includes signaling different quantization strength for macroblocks in a region on at least one boundary edge of the frame, and wherein the signaling uses a syntax that includes coding a choice of the region from among the boundary edges of the frame; reading the signaled different quantization from the compressed bit stream; and dequantizing, by an inverse quantizer, the macroblocks of the frame according to the signaled different quantization.