MPEG PS和TS格式介绍.ppt

TS introduction ----- some features TS is a stream for communicating or storing one or more programs and other data in environments in which significant errors may occur TS may be either fixed or variable rate, TS rate is defined by the values and locations of PCR TS is made up of TS packets, each are 188 bytes in length TS introduction ----- TS packet(1) TS packet begin with a 4 byte prefix, which contains a 13-bit PID PID identifies the contents of the data contained in the TS packet via PSI table There are 4 PSI tables 1. Program Association Table (PAT) 2. Program Map Table (PMT) 3. Conditional Access Table (CAT) 4. Network Information Table (NIT) TS introduction ----- TS packet(2) TS introduction ----- TS packet(3) TS introduction ----- TS packet(4) sync_byte a fixed 8 bit field, value is 0x47 transport_error_indicator ‘1’ indicates that at least 1 uncorrectable bit error exists in the associate packet payload payload_unit_start_indicator * to PES packet,’1’ indicates this packet payload is a start of this PES packet * to PSI data, ’1’ indicates this packet payload is a start of current PSI data * to empty packet, always is ‘0’ transport_priority ‘1’ indicates this TS packet has a greater priority than other PID indicates the type of stored data in packet payload TS introduction ----- TS packet(5) transport_scrambling_control indicates the scrambling mode of TS packet payload, ’00’ ------ not scrambled, ’01’ to ’11’ ------ user defined adaptation_field_control indicates the TS packet header whether is followed with an adaptation field or/and payload ’00’ ------ reserved by ISO 13818-1, ’01’ ------ not adaptation field, payload only ’10’ ------ adaptation field, not payload, ‘11’ ----- adaptation field followed by payload continuity_counter incrementing with each TS packet with the same PID, to adaptation_field_control is ’00’ or ’01’, isn’t incremented data_byte cont