Patent ID: 7899080

Claim:
A demultiplexer for extracting effective payloads from a multiplexed stream comprising a plurality of packets, each of which includes a packet header and a payload, and ineffective data with an unknown length located between packets, the demultiplexer comprising: a packet header detector operable to detect packet headers in the multiplexed stream; and a payload separator operable to separate payloads included in the multiplexed stream based on detection results of the packet header detector, wherein: a finite search length is set in the packet header detector, the packet header detector searches for a start code included in a packet header which is to be detected through a range designated by the search length so as not to detect a false start code in the ineffective data, the search length is larger than the length of the start code, wherein: a plurality of search lengths are set in the packet header detector, and the packet header detector selectively uses the plurality of search lengths such that: if the length of the ineffective data previous to a packet header which is to be detected is long, the packet header detector selects a long search length, and if the length of the ineffective data previous to a packet header which is to be detected is short, the packet header detector selects a short search length.