Patent ID: 8553767

Claim:
A video decoding method comprising: decoding video encoded data using a predictive picture signal for a video signal to generate a decoded picture signal; compressing the decoded picture signal to generate a compressed picture signal; storing the decoded picture signal in a first memory; storing the compressed picture signal, which is a compressed version of the decoded picture signal stored in the first memory, in a second memory; decompressing the compressed picture signal read from the second memory to generate a compressed/decompressed picture signal; selecting one of the decoded picture signal read from the first memory and the compressed/decompressed picture signal as a reference picture signal according to at least one of a coding type of the video encoded data in picture unit and a prediction mode in block unit; storing the reference picture signal in a third memory; and performing motion compensation on the reference picture signal to generate a predictive picture signal, wherein the selecting includes selecting the decoded picture signal read from the first memory at the time that the prediction mode in block unit indicates a mode for generating the predictive picture signal from a forward prediction pixel block, and selecting two reference blocks of the compressed/decompressed picture signal at the time that the prediction mode in block unit a mode for generating the predictive picture signal from a dual prime prediction pixel block.