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Hydrogenaudio Forums > Lossy Audio Compression > MP3 > MP3 - General
jmartis
I know that Lame by default writes its header with Lame version/vbr info/lowpass/psymodel etc. When the "-t" switch is used, it should disable Lame header. But it seems to do not disable it completely - when the mp3 file is analyzed in Encspot, it still knows which Lame version was used even when the file was encoded with the "-t" switch. So where does Lame squeeze its version info???

Thx, J.M.
greynol
Enscpot does not determine what Lame verion is used (or even that the codec used was Lame) from the Lame header.

Lame and its version can be found at the end of the file.
jmartis
QUOTE(greynol @ Jul 12 2006, 20:25) *

Enscpot does not determine what Lame verion is used (or even that the codec used was Lame) from the Lame header.

Lame and its version can be found at the end of the file.

So this means that the Lame version will ALWAYS be stored at the end of the file no matter what switches I use?
greynol
I'd say this is a safe assumption to make. Do you mind if I ask why you don't want a Lame header? True gapless playback will be impossible without one.
jmartis
QUOTE(greynol @ Jul 12 2006, 20:45) *

I'd say this is a safe assumption to make. Do you mind if I ask why you don't want a Lame header? True gapless playback will be impossible without one.

I was just wondering how Encspot was getting the version without the Lame header tongue.gif

J.M.
SebastianG
AFAIK LAME includes its own version string into the bitreservoir to fill space that's wasted anyways. Something along those lines. (Usually at the start/end when there's silence).
Jojo
...nevermind...
smack
QUOTE(jmartis @ Jul 12 2006, 19:36) *
So this means that the Lame version will ALWAYS be stored at the end of the file no matter what switches I use?
Whenever LAME needs to insert non-audio data to pad a frame it includes its own version string. The contents of this padding data are completely irrelevant to the mp3 decoder, btw. Zero bytes or random data or secret messages could be included, too.

Most (but not all) files encoded by LAME contain padding data and thus the encoder version string. Also, a tool like mp3packer can be used to strip padding data from mp3 files without changing the audio data.

So, the answer to your question is: no, not always.
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