Abstract: The Program Clock Reference (PCR) is the time base of decoding video and audio in MPEG-2 system. A MPEG-2 decoder uses the PCR to control the decode time and the present time of video and to realize the synchronization of video and audio. The PCR correction is one of the key technique for the MPEG-2 remultiplexer design. This paper proposes an improved and practical method of the PCR correction for the design of MPEG-2 remultiplexer through analysis of problems in the PCR correction method currently used in MPEG-2 remultiplexer. With the correction method, the re-multiplexer can solve the problem that the timing of the PCR value described in the PCR field is not in accord with the timing of the decoder received in the PCR field in the packet, due to the buffering of the MPEG-2 signal in the processing of remultiplexing, therefore, it can solve the problems of PCR jitter and buffer overflow in the processing of MPEG-2 decode, which would happen with a wrong PCR correction method. A decoder can reconstruct the clock signal of the encoder from the PCR value, and keep the clock in synchronization between decoder and encoder. Furthermore the audio signal after re-multiplexer with the new PCR correction method can meet FM synchronous broadcast requirements for a more accurate time.
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Received: 02 June 2010
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