Patent ID: 7167521

Claim:
A computer system for decoding an encoded alpha-map signal, comprising: demultiplexer means for demultiplexing a alpha-map code and a size conversion ratio information code from the encoded alpha-map signal; decoding means for decoding the alpha-map code to a binary image; up-sampling means for up-sampling the binary image as the alpha-map code output from said decoding means in accordance with the size conversion ratio information code to output the up-sampled image as a decoded video signal; motion compensation means for generating a motion compensation signal on the basis of a previous decoded video signal and a motion vector signal; and down-sampling means for down-sampling the motion compensation signal in accordance with the size conversion ratio information to output the down-sampled motion compensation signal to said decoding means, said decoding means decoding the alpha-map code in accordance with the motion estimation/compensation signal and the size conversion ratio information.