* alsa-lib resamping error
@ 2003-01-22 17:38 Paul Davis
2003-01-23 16:20 ` Takashi Iwai
0 siblings, 1 reply; 3+ messages in thread
From: Paul Davis @ 2003-01-22 17:38 UTC (permalink / raw)
To: alsa-devel
if you try to play a 22.05kHz stream on hardware that supports 32kHz
and 44.1kHz but not 22.05kHz, alsa-lib's plughw layer chooses to use
32kHz and resamples. this seems like an error to me: it would be much
better to choose 44.1kHz and do simple integer resampling. that is:
the search for the best rate should first try integer multiples and
divisors of the desired rate, not the "closest" rate.
--p
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: alsa-lib resamping error
2003-01-22 17:38 alsa-lib resamping error Paul Davis
@ 2003-01-23 16:20 ` Takashi Iwai
2003-01-27 11:38 ` Takashi Iwai
0 siblings, 1 reply; 3+ messages in thread
From: Takashi Iwai @ 2003-01-23 16:20 UTC (permalink / raw)
To: Paul Davis; +Cc: alsa-devel
At Wed, 22 Jan 2003 12:38:31 -0500,
Paul Davis wrote:
>
> if you try to play a 22.05kHz stream on hardware that supports 32kHz
> and 44.1kHz but not 22.05kHz, alsa-lib's plughw layer chooses to use
> 32kHz and resamples. this seems like an error to me: it would be much
> better to choose 44.1kHz and do simple integer resampling. that is:
> the search for the best rate should first try integer multiples and
> divisors of the desired rate, not the "closest" rate.
agreed, it would be better.
but... errm... changing this in alsa-lib is like going into a big
labyrinth for me :)
Takashi
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^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: alsa-lib resamping error
2003-01-23 16:20 ` Takashi Iwai
@ 2003-01-27 11:38 ` Takashi Iwai
0 siblings, 0 replies; 3+ messages in thread
From: Takashi Iwai @ 2003-01-27 11:38 UTC (permalink / raw)
To: Paul Davis; +Cc: alsa-devel
At Thu, 23 Jan 2003 17:20:02 +0100,
I wrote:
>
> At Wed, 22 Jan 2003 12:38:31 -0500,
> Paul Davis wrote:
> >
> > if you try to play a 22.05kHz stream on hardware that supports 32kHz
> > and 44.1kHz but not 22.05kHz, alsa-lib's plughw layer chooses to use
> > 32kHz and resamples. this seems like an error to me: it would be much
> > better to choose 44.1kHz and do simple integer resampling. that is:
> > the search for the best rate should first try integer multiples and
> > divisors of the desired rate, not the "closest" rate.
>
> agreed, it would be better.
>
> but... errm... changing this in alsa-lib is like going into a big
> labyrinth for me :)
and after a long wandering in the labyrinth, the changes are on cvs
now (both for alsa-driver and alsa-lib).
the new code will try the integer multiples at first.
i hope this works correctly...
Takashi
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^ permalink raw reply [flat|nested] 3+ messages in thread
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2003-01-22 17:38 alsa-lib resamping error Paul Davis
2003-01-23 16:20 ` Takashi Iwai
2003-01-27 11:38 ` Takashi Iwai
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