MPEG-2

MPEG-2 is an extended version of the MPEG-1 standard for video and audio streams. It is used in digital TV broadcasts and DVDs. The ISO/IEC 13818 group of standards specify the details of the standard.

A number of patents relate to various aspects of the format, but they are starting to expire as of 2012, with most expired by 2015 (but a few hanging on a little longer). As long as any of the patents are in effect, a licensing body with control over the entire patent pool demands royalties from everybody producing anything using the format.

The popular MP3 audio format is based on layer 3 of MPEG-1 and MPEG-2.

The AAC audio format is based on MPEG-2 Part 7.

Data within an MPEG-2 stream is divided into packets in the Packetized Elementary Stream format.

Formats
There are separate articles for these formats:
 * AAC
 * MP3
 * MPEG Audio Layer I (MP1)
 * MPEG Audio Layer II (MP2)
 * MPEG Elementary Stream
 * MPEG Program Stream
 * MPEG Transport Stream
 * Packetized Elementary Stream

Other formats based on MPEG-2:
 * Enhanced VOB
 * M2TS
 * VOB

Specifications
These documents are not free to download. This is not a complete list of the MPEG-2 Parts and Amendments.
 * ISO/IEC 13818-1:2013 - Part 1: Systems
 * Part 1 is also published as ITU-T Rec. H.222.0
 * ISO/IEC 13818-2:2013 - Part 2: Video
 * Part 2 is also published as ITU-T Rec. H.262
 * ISO/IEC 13818-3:1998 - Part 3: Audio
 * ISO/IEC 13818-7:2006 - Part 7: Advanced Audio Coding

Links

 * Wikipedia article
 * MPEG official website
 * Official page on MPEG-2
 * Forthcoming changes to MPEG-1 and MPEG-2 variants in next PRONOM/DROID signature release