Part 3 of the
MPEG-2
MPEG-2 (a.k.a. H.222/H.262 as was defined by the ITU) is a standard for "the generic coding of moving pictures and associated audio information". It describes a combination of lossy video compression and lossy audio data compression methods ...
standard (formally known as ISO/IEC 13818-3, also known as MPEG-2 Audio or MPEG-2 BC) defines audio coding:
*
MPEG Multichannel
__NOTOC__
MPEG Multichannel, also known as MPEG-2 Backwards Compatible, or MPEG-2 BC, is an extension to the MPEG-1 Layer II audio compression specification, as defined in the MPEG-2 Audio standard (ISO/IEC 13818-3) which allows it provide up to ...
- It enhances
MPEG-1
MPEG-1 is a Technical standard, standard for lossy compression of video and Audio frequency, audio. It is designed to compress VHS-quality raw digital video and CD audio down to about 1.5 Mbit/s (26:1 and 6:1 compression ratios respectively ...
's audio by allowing the coding of audio programs with more than two
channels, up to 5.1 multichannel. This method is backwards-compatible (also known as MPEG-2 BC
), allowing MPEG-1 audio decoders to decode the two main stereo components of the presentation.
* MPEG-2 Part 3 also defined additional bit rates and sample rates for
MPEG-1 Audio Layer I
MPEG-1 Audio Layer I, commonly abbreviated to MP1, is a lossy audio codec and one of three audio formats included in the MPEG-1 standard. For files only containing MP1 audio, the file extension .mp1 is used.
It is a deliberately simplified ver ...
,
MPEG-1 Audio Layer II
MP2 (formally MPEG-1 Audio Layer II or MPEG-2 Audio Layer II, sometimes incorrectly called Musicam) is a lossy audio compression format. It is standardised as one of the three audio codecs of MPEG-1 alongside MPEG-1 Audio Layer I (MP1) and M ...
and
MPEG-1 Audio Layer III
MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) is a coding format for digital audio developed largely by the Fraunhofer Society in Germany under the lead of Karlheinz Brandenburg. It was designed to greatly reduce the amount ...
(the first version of
MP3
MP3 (formally MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) is a coding format for digital audio developed largely by the Fraunhofer Society in Germany under the lead of Karlheinz Brandenburg. It was designed to greatly reduce the amount ...
).
[Predrag Supurovic]
MPEG Audio Frame Header
Retrieved on 2009-07-11
The MPEG-2 Part 3 should not be confused with MPEG-2 Part 7: AAC a.k.a. MPEG-2 NBC (Non-Backward Compatible) - the MPEG-2
Advanced Audio Coding
Advanced Audio Coding (AAC) is an audio coding standard for lossy digital audio compression. It was developed by Dolby, AT&T, Fraunhofer and Sony, originally as part of the MPEG-2 specification but later improved under MPEG-4.ISO (2006ISO/ ...
with support for multichannel encoding (up to 48 channels).
Overview
MPEG-2 Part 3 introduced new audio encoding methods compared to MPEG-1 Part 3:
MPEG-2 BC (backward compatible with MPEG-1 audio formats)
* low bitrate encoding with halved sampling rate (MPEG-1 Layer
1/
2/
3 LSF - "Low Sampling Frequencies")
* multichannel encoding with up to 5.1 channels
References
{{MPEG
#03