Re: LAME MP3 file trailers

"Reinier Bakels" <[email protected]>
Newsgroups gmane.comp.audio.mp3.lame
Message-ID <40664A2F0CF44BD4A38AA300136A3AE9@RBB2009>
> The text LAME is not only used to identify the encoder but also as the 
> content used when padding is needed. Instead of adding random data or 
> zeroes,  it > adds that text.
> As such, it can be at any place (depending on the padding needed)

I did some further investigations. Indeed the characters 'LAME' appear 
numerous times in a MP3 file created by LAME.
It appears that if I use the values contained in the 'Info'/'LAME' structure 
in the first frame (notably the net file size), I get consistent results 
*IF* I assume that there may be extra  bytes at the end without meaning, 
where the number of extra bytes = the actual file size the size of any ID3 
meta-information in the beginning of the file.
Sometimes the extra bytes are binary zero, sometimes they start like a 
regular MP3 frame, but they are much shorter.

IN SUM MY QUESTION IS: Is it true indeed that LAME may add some meaningsless 
bytes at the end? (typically less than 200).

Remember my objective was to check file integrity - then extra bytes at the 
end are confusing.

Sorry, perhaps I was too early with my previous response ...

reinier


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