Sustainability of Digital Formats: Planning for Library of Congress Collections

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MPEG-2, Main Profile

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Format Description Properties Explanation of format description terms

Identification and description Explanation of format description terms

Full name Information technology -- Generic coding of moving pictures and associated audio information (formal name), MPEG-2 (common name), Main Profile
Description Permits the use of Intra-coded (I) frames, predicted (P) frames, and bidirectionally predicted (B) frames. Conformance points for this bitstream exist at the following levels: Low, Main, High-1440, and High. At the Main Level, the broadcast-stream picture size is 720x576 pixels (non-square pixels), with color sampling of 4:2:0 and a maximum data rate of 15 Mb/s.
Production phase Generally a final-state (end-user delivery) format; may be used as a middle-state (broadcast production) format.
Relationship to other formats
    Subtype of MPEG-2, MPEG-2 Video Encoding (H.262)
    Used by MPEG-2_MP_layer_2, MPEG-2, Main Profile, with Layer II Audio Encoding

Local use Explanation of format description terms

LC experience or existing holdings See MPEG-2_family
LC preference See MPEG-2_family

Sustainability factors Explanation of format description terms

Disclosure Open standard. See MPEG-2
    Documentation See MPEG-2
Adoption MPEG-2_MP (Main Profile) is used by broadcasters and cablecasters, who may also use MPEG-2_422 (4:2:2 Profile). The Vanderbilt University TV News Archive uses MPEG-2_MP when reformatting its analog videotapes and when making new off-air recordings.
    Licensing and patents See MPEG-2.
Transparency See MPEG-2.
Self-documentation See MPEG-2.
External dependencies See MPEG-2.
Technical protection considerations See MPEG-2.

Quality and functionality factors Explanation of format description terms

Moving Image
Normal rendering Good support.
Clarity (high image resolution) See MPEG-2. At a given picture size, data rate, and encoding algorithm, MPEG-2_MP (Main Profile) will produce greater clarity than MPEG-2_SP (Simple Profile) but less than MPEG-2_422 (4:2:2 Profile).
Functionality beyond normal rendering See MPEG-2.

File type signifiers and format identifiers Explanation of format description terms

Tag Value Note
Filename extension mpg
mpeg
There is no explicit MPEG-2 file format; MPEG-2 content "ready to be delivered" is exchanged in files with these extensions.
Internet Media Type See related format. 

See MPEG-2

Magic numbers See related format. 

See MPEG-2


Notes Explanation of format description terms

General  
History  

Format specifications Explanation of format description terms


Useful references

URLs


Last Updated: Friday, 17-Feb-2017 14:45:58 EST