SPATIAL SCALABLE COMPRESSION

摘要

A method and apparatus for providing spatial scalable compression of a video stream is disclosed. The video stream is downsampled to reduce the resolution of the video stream. The downsampled video stream is encoded to produce a base stream. The base stream is decoded and upconverted to produce a reconstructed video stream. The reconstructed video stream is subtracted from the video stream to produce a residual stream. It is then determined which segments or pixels in each frame have a predetermined chance of having a predetermined characteristic. A gain value for the content of each segment or pixel is calculated, wherein the gain for pixels which have the predetermined chance of having the predetermined characteristic is biased toward 1 and the gain for other pixels is biased toward 0. The residual stream is multiplied by the gain values so as to remove bits from the residual stream which do not correspond to the predetermined characteristic. The resulting residual stream is encoded and outputted as an enhancement stream.