[Speex-dev] Audio Speed Variability

Alexander Chemeris Alexander.Chemeris at sipez.com
Fri Oct 5 02:29:36 PDT 2007


On 10/5/07, John Miles <jmiles at pop.net> wrote:
> Longer answer: Sound chips usually run at one of those rates, often either.
> Those rates are more or less guaranteed to work properly.  Most chips don't
> support other rates directly; a software resampler in the driver is used
> instead.  Unfortunately, Microsoft released a horribly-broken reference
> resampler implementation to sound hardware OEMs a few years ago, and many of
> them still use it.  On their sound cards, if you ask for 11025 Hz, for
> example you're likely to get 11100 Hz or something similarly-imprecise.
> That obviously causes cumulative latency/slippage problems.

Is there any statistic regarding which chips operate on which frequency?
I'm wondering will it be safe to use 48kHz rather then 44.1kHz, as it is
a multiple of 16kHz, so it should be easier, faster and less lossy to
convert to/from it.

Alexander Chemeris.

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