MPEG transport stream

MPEG transport stream (MPEG-TS, MTS) or simply transport stream (TS) is a standard digital container format for transmission and storage of audio, video, and Program and System Information Protocol (PSIP) data.

Transport stream is specified in MPEG-2 Part 1, Systems, formally known as ISO/IEC standard 13818-1 or ITU-T Rec.

Many streams are often mixed together, such as several different television channels, or multiple angles of a movie.

Due to the tiny packet size, streams can be interleaved with less latency and greater error resilience compared to program streams and other common containers such as AVI, MOV/MP4, and MKV, which generally wrap each frame into one packet.

Transport streams tend to be broadcast as constant bitrate (CBR) and filled with padding bytes when not enough data exists.

[b] The 188-byte packet size was originally chosen for compatibility with Asynchronous Transfer Mode (ATM) systems.

In most applications, time-division multiplexing will be used to decide how often a particular PID appears in the transport stream.

To enable a decoder to present synchronized content, such as audio tracks matching the associated video, at least once each 100 ms, a program clock reference (PCR) is transmitted in the adaptation field of an MPEG-2 transport stream packet.

Some transmission schemes, such as those in ATSC and DVB, impose strict constant bitrate requirements on the transport stream.

In order to ensure that the stream maintains a constant bitrate, a multiplexer may need to insert some additional packets.

[18][19] The timecode allows quick access to any part of the stream either from a media player, or from a non-linear video editing system.

Blu-ray Disc video titles authored with menu support are in the Blu-ray Disc Movie (BDMV) format and contain audio, video, and other streams in a BDAV container, which is based on the MPEG-2 transport stream format.

This enables transport streams of a BDAV converted digital broadcast to be recorded as they are with minimal alteration of the packets.