Picture encoding method and apparatus and picture decoding method and apparatus

摘要

A picture decoding apparatus characterized by comprising: input means (200) for receiving an input code stream containing a video code stream obtained by encoding a video signal and a motion-compensated reference picture code stream obtained by encoding a reference picture signal; first decoding means (202-204) for decoding the motion-compensated reference picture code stream contained in the input code stream to generate a first reference picture signal; and second decoding means (209-211) for decoding the video code stream contained in the input code stream by selectively using one of a second reference picture signal obtained from a previous picture signal and the first reference picture signal to generate a playback picture signal, the second decoding means including a frame memory (208) which stores the playback picture signal as the second reference picture signal, and motion compensation means (207) for subjecting one of the second reference picture signal read out from the frame memory and the first reference picture signal to motion compensation.