Vorbis dev - Sep 2001 - Encoder bug (studder in an encoding)

I'm not sure if this is an encoder bug or just a weakness in the
algorithm, but I have a sample of "Time" from Dark Side of the Moon,
where
the clocks go off in the beginning.  There's one clock in the right
channel 34 seconds in just as they're winding down.  

In the vorbis encoding, the clock 'studders' and there seem to be some
low-frequency pops.  A bit like the waveform is being very rapidly cycled
in and out of the bistream.  Its quite noticable.

Samples are posted at http://ephemeralfic.org/time.flac, time128.ogg,
time160.ogg, and time192.ogg (it occurs at all three bitrates).

Encoder is RC2 oggenc from the linux RPM's (alienized on Debian testing,
i386).

        Scott


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On Sun, Sep 02, 2001 at 11:34:04PM -0700, Scott G. Miller
wrote:
> I'm not sure if this is an encoder bug or just a weakness in the
> algorithm, but I have a sample of "Time" from Dark Side of the
Moon, where
> the clocks go off in the beginning.  There's one clock in the right
> channel 34 seconds in just as they're winding down.  
> 
> In the vorbis encoding, the clock 'studders' and there seem to be
some
> low-frequency pops.  A bit like the waveform is being very rapidly cycled
> in and out of the bistream.  Its quite noticable.
> 
> Samples are posted at http://ephemeralfic.org/time.flac, time128.ogg,
> time160.ogg, and time192.ogg (it occurs at all three bitrates).
> 
> Encoder is RC2 oggenc from the linux RPM's (alienized on Debian
testing,
> i386).
BTW, no reason to use RPMs; debian has official Ogg packages.

Secondly, these RPMs were broken due to an old egcs bug, and the
result is the artifact you describe.  Fixed RPMs are now up on the
site.

Monty

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