On Fri, Jun 07, 2002 at 08:30:23PM +0200, Kristian Peters wrote:
> Martin Wolters <[EMAIL PROTECTED]> wrote:
> > I expect about 1200 - 1230 added zeros at the beginning. The number of 
> > added zeroes in the end can vary. There is a finite number of 
> > possibilities from the mp3 algorithm (like for the beginning), plus a 
> > number of zero padding samples that is depend on the size of the 
> > original wav-file. (In order to fill up frames).
> 
> Oh.. Not only zeros are added at the beginning. I calculated that 9024 bytes are 
>added by mpg123. (It's not easy to determine that cause the output differs.. But I 
>hope the number is correct.)
> 
> 9024 / (channels) / sizeof(bits) == 1128.
> 
> (I used a 16bit stereo wav.)
> 
> I'll test other decoders. Hopefully that one will not vary.
> 
> Thanks, *Kristian
> 
>   :... [snd.science] ...:
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When I was doing some codec analysis, I found it necessary to find the 
maximum of the cross-correlation of the source and destination files and 
zero-pad the files to align them. A little more work to setup your test, 
but it fixes that kind of problem automatically.

Regards,
Mark
mark.rages.net

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