VIDEO AND GRAPHICS SYSTEM WITH A DATA TRANSPORT PROCESSOR

A video and graphics system uses multiple transport processors to receive compressed data streams to perform PID and section filtering as well as DVB and DES decryption and to demultiplex them. The compressed data streams may include in-band and out-of-band MPEG Transport streams. The video and graphics system processes the PES into digital audio, MPEG video and message data. A core transport processor includes a PCR recovery module for extracting PCRs contained in the compressed data streams and for providing the extracted PCRs to a video transport processor and an audio decode processor. The PCR recovery module has a direct load capability for receiving user defined PCRs and outputting them instead of outputting the extracted PCRs. The PCR recovery module extracts PCRs from both MPEG Transport streams and DIRECTV transport streams. The core transport processor may also include a transport recorder for storing portions of compressed data streams and a playback circuit for reading the stored portions of the compressed data streams. The playback circuit includes a throttling mechanism and a hold mechanism to prevent buffer overflow.