Data compression for video with preprocessing

摘要

The invention relates to a method of compressing a video signal for transmission to a decoder of a receiving terminal, the method comprising: receiving a video signal comprising a plurality of frames, each frame comprising a plurality of portions of video data; for each of a plurality of target ones of said portions, generating difference data representing a difference between the target image portion and a respective reference portion; and outputting the difference data in an encoded bitstream; wherein the method comprises, prior to generating the difference data, modifying at least one of said target and reference portions based on a measure of human sensitivity to the video data, so as to reduce a number of bits required to encode the difference data.