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Topic: what is mpeg2 layer 3? (Read 5694 times) previous topic - next topic

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  • rdo
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what is mpeg2 layer 3?
Hi everyone,

I've got some files that have mp3 extension.
My player shows that they have bitrate 80kbs and frequency 225000.
EncSpot shows me that they are of type mpeg2 layer III.

I wonder what is this mpeg2 layer III? I thought mp3 is of type mpeg1 layer III.

I find that my files are very small in size and still the quality is acceptable.
Anyone that has experience with such encoding? Does it worth to try it? How to encode and how to achieve good results?

  • DreamTactix291
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what is mpeg2 layer 3?
Reply #1
Has to do with the samplerate and possible bitrates.

Code: [Select]
         Sample Rates   Bitrates
MPEG-1  32, 44.1,  48  32, 40, 48, 56, 64, 80, 96, 112, 128, 160, 192, 224, 256, 320
MPEG-2  16. 22.05, 24  8,  16, 24, 32, 40, 48, 56, 64,  80,  96,  112, 128, 144, 160
  • Last Edit: 16 August, 2005, 05:48:58 AM by DreamTactix291
Nero AAC 1.5.1.0: -q0.45

what is mpeg2 layer 3?
Reply #2
If the sampling rate is lower than 16 KHz, the files are MPEG 2.5.
AFAIK, MPEG 2.5 is not an official standard but was introduced to support low sampling rates.
  • Last Edit: 16 August, 2005, 05:58:51 AM by Sebastian Mares

  • SebastianG
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what is mpeg2 layer 3?
Reply #3
The mpeg2 specification not only contains a low sampling rate extension but also a multichannel extension.

Sebi

what is mpeg2 layer 3?
Reply #4
I noticed that the mp3 sound files that are part of the game "Sid Meier's Alpha Centauri" are MPEG2.

  • DreamTactix291
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what is mpeg2 layer 3?
Reply #5
Quote
The mpeg2 specification not only contains a low sampling rate extension but also a multichannel extension.

Sebi
[a href="index.php?act=findpost&pid=320445"][{POST_SNAPBACK}][/a]
A multichannel extension that has never had an encoder implementation AFAIK
Nero AAC 1.5.1.0: -q0.45

  • rjamorim
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what is mpeg2 layer 3?
Reply #6
Quote
A multichannel extension that has never had an encoder implementation AFAIK [a href="index.php?act=findpost&pid=320526"][{POST_SNAPBACK}][/a]


There is an MP2 encoder. Check RRW.
Get up-to-date binaries of Lame, AAC, Vorbis and much more at RareWares:
http://www.rarewares.org

  • DreamTactix291
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what is mpeg2 layer 3?
Reply #7
Alright no MP3 implementation.  The MP2 encoder sounds interesting though
Nero AAC 1.5.1.0: -q0.45

  • gasmann
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what is mpeg2 layer 3?
Reply #8
couldn't this be mp3pro, too? I mean if you play a mp3pro file in a non-mp3pro-compatible standard mp3 player a 44kHz file ends up in a 22kHz standard mp3 file. The Spectral Band Replication (or whatever its called  ) will not be seen by a standard mp3 decoder and so there are no higher frequencies available even though they are in the mp3pro file.
flac 1.2.1 -8 (archive) | aoTuVb5.7 -q 4 (pc, s1mp3)

  • bond
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what is mpeg2 layer 3?
Reply #9
mp3pro is not part of the official mp3 standard
I know, that I know nothing (Socrates)

  • SebastianG
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what is mpeg2 layer 3?
Reply #10
though, it makes use of mpeg2 (half the sampling rate) layer 3 for the "compatibility layer"

Sebi