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I see here http://en.wikipedia.org/wiki/MP3 that MP3 file consists of MP3 headers interchanged with MP3 data. MP3 header consist of few bytes.

But here is my MP3 file dump with ID3 tag cut. Header is highlighted with blue.

MP3 file dump with ID3 tag cut

You can see that "LAME3.96" text is highlighted with green. What does it does there? Is this a part of MP3 elementary stream? Or this is the part of some headers I didn't tag?

hippietrail
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Dims
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1 Answers1

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LAME is an MP3 encoder, which is a program that takes an uncompressed audio source and outputs a compressed MP3. That piece of text there just indicates that the file was compressed using the LAME encoder. According to the LAME SourceForge page, the latest version is 3.99, pretty close to what you got inserted into the header of that file.

So don't worry, nobody tried to insult your MP3 file! :P

Andrei Bârsan
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    The header is 4 bytes. So "LAME" is not in the header, but in the body. In the body it should be frequency table. I want to interpret file, not catch some spies! :) – Dims Jun 26 '12 at 15:17
  • Yes, I have checked some Mp3 files myself and they, too have LAME in their body. Other than that, I don't know what the problem could be. Perhaps asking on the LAME mailing list could yield a better answer. – Andrei Bârsan Jun 29 '12 at 12:42
  • Following the great history of GNU naming, LAME originally stood for LAME Ain't an Mp3 Encoder. from: http://lame.sourceforge.net/about.php – Daniel Mošmondor Feb 17 '15 at 21:50
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    MP3 files can have an extra header embedded within the first audio frame which represents silence and has unused space. Originally this was done by Xing and only for VBR files, but now you'll find them in many MP3 files and LAME adds both `Xing` and `Info`, the latter for CBR files. Sometimes `LAME` occurs in this spot but doesn't seem to have any function. More commonly it occurs at a later offset in the frame and I think it also has no meaning in that position. I'm not sure if it's some kind of watermark or a minor bug due to not clearing a buffer in a place where that makes no difference. – hippietrail Apr 29 '21 at 11:00