MP3 frames, Bitrate combinations |
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MP3 frames, Bitrate combinations |
 May 24 2003, 13:24
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#1
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 Group: Members Posts: 3620 Joined: 14-May 03 From: Bad Herrenalb Member No.: 6613  |
Hello,
While looking around for some MP3 documentation I have came across the following sites: As you can see, the bitrate tables are different. ID3.org says that MPEG 2 Layer 2 varies between 32 and 384, while MP3' Tech says that it varies between 8 and 160. Which of the two tables is correct? Regards, Sebastian Mares -------------------- http://listening-tests.hydrogenaudio.org/sebastian/
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May 24 2003, 14:42
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#2
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 xcLame and OggDropXPd Developer Group: Developer Posts: 3706 Joined: 30-September 01 From: Bracknell, UK Member No.: 111 |
I should go back and read them again if I were you. They say the same thing.
 You're confusing the Version number with the Layer number.
-------------------- John
---------------------------------------------------------------- My compiles and utilities are at http://www.rarewares.org/ |
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May 24 2003, 16:41
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#3
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Group: Members Posts: 3620 Joined: 14-May 03 From: Bad Herrenalb Member No.: 6613 |
Actually, I don't!
MP3' Tech says that the lowest bitrate for MPEG 2 Layer II AND III is 8 kbps, while ID3.org says that ONLY MPEG 2 Layer III starts at bitrate 8 kbps. -------------------- http://listening-tests.hydrogenaudio.org/sebastian/
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May 24 2003, 16:56
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#4
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xcLame and OggDropXPd Developer Group: Developer Posts: 3706 Joined: 30-September 01 From: Bracknell, UK Member No.: 111 |
QUOTE (Sebastian Mares @ May 24 2003 - 03:41 PM) Actually, I don't! MP3' Tech says that the lowest bitrate for MPEG 2 Layer II AND III is 8 kbps, while ID3.org says that ONLY MPEG 2 Layer III starts at bitrate 8 kbps. Hmmm, I think my brain must have been out to lunch!!  I would tend to trust Gabriel's (mp3tech) since he is a LAME developer.
-------------------- John
---------------------------------------------------------------- My compiles and utilities are at http://www.rarewares.org/ |
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May 24 2003, 19:59
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#5
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Group: Members Posts: 674 Joined: 29-September 01 Member No.: 63 |
I shall resist against making some mean, sarcastic remarks about the intelligence of the creators of id3v2.
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May 24 2003, 20:14
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#6
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Group: Members Posts: 3620 Joined: 14-May 03 From: Bad Herrenalb Member No.: 6613 |
 Yes...
-------------------- http://listening-tests.hydrogenaudio.org/sebastian/
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May 25 2003, 10:46
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#7
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 LAME developer Group: Developer Posts: 2950 Joined: 1-October 01 From: Nanterre, France Member No.: 138 |
My copy of the ISO standard gives the same numbers as me.
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May 25 2003, 10:54
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#8
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LAME developer Group: Developer Posts: 2950 Joined: 1-October 01 From: Nanterre, France Member No.: 138 |
I checked id3.org, and they are listing the mpeg2 bitrates for layer I and II to be identical to mpeg1 ones.
This is wrong in case of use of mpeg2 low sampling frequencies. Anyway, layer II lsf should be quite rare. In the standard, the table listing the allowed stereo modes (as in mpeg1) is missing. It seems that the ISO comitee though about the following: *if you want to reduce bitrate, then use layer III and not layer II *if you want multichannel, use layer II, as it's less complew than layer III Layer III multichannel seems to be completely defined in the standard, however there is no encoder. Even in the ISO compliance bitstreams, there is only 1 layer III mc test sample, and this one is synthetic (not produced by an encoder) |
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May 25 2003, 11:25
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#9
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Group: Members Posts: 3620 Joined: 14-May 03 From: Bad Herrenalb Member No.: 6613 |
Thanks for the information Gabriel!
By the way, would it be possible for you to have a look at this tread and maybe answer some of my questions, please? Best regards, Sebastian -------------------- http://listening-tests.hydrogenaudio.org/sebastian/
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Lo-Fi Version | Time is now: 19th May 2013 - 21:58 |
