Transcoder, recorder, and transcoding method

摘要

A transcoder for decoding a motion picture stream encoded by using a first coding scheme, which provides intraframe coding and interframe predictive coding, and encoding the decoded motion picture stream by using a second coding scheme, the transcoder including: at decoder for decoding an input motion picture stream and detecting sub-information indicating whether an intraframe coding scheme or an interframe predictive coding scheme is used; and an encoder for changing the frame to be referenced at the time of coding depending on whether the sub-information indicates the use of the intraframe coding scheme or the interframe predictive coding scheme.