Transport stream demultiplexer which detects null packets and does not write their payload into memory

摘要

A transport stream demultiplexer (10) which receives transport stream packets and outputs data included the packets, has a device (12) which judges whether a received transport stream packet is a null packet. If the received transport stream packet is a null packet, it prohibits writing data included in the received transport stream packet payload into a local buffer. Packet header and status data is stored for null packets, and dummy data may be added to the header to regenerate the null packet for output. The system saves bandwidth of the local buffer memory by reducing the number of write operations. The system may be utilised with a digital television receiver, for video packet transport streams.