Re: LAME MP3 file trailers

> 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)

Thanks for the quick reply. But then the question why LAME pads at all.

Normally MP3 files end with an ID3V1 tag and/or an APE tag, or none of the 
two. Preceding these trailing tags usually is the last MP3 frame (starting 
with eleven '1' bits). The size of MP3 follows from the information in its 
(4 byte) header. In fixed bit rate files, the size ofall the frames is the 
same, +/- 1 depending on padding.

The text "LAME3.99.3" is typically close to the end of the file, followed by 
a series of hexadecimal 0xAA characters, or hexadecimal 0x55 (ASCII 'U') 
characters. After these characters, there often appears to follow another, 
shorter MP3 frame (starting with eleven '1' bits).

Again, my purpose is to check the integrity of MP3 files. With my present 
knowledge, I cannot do that for MP3 files written by LAME. Please help!

reinier 


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