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Subject: Re: pcm_set_frequency is ignored

Re: pcm_set_frequency is ignored

From: Magnus Holmgren <>
Date: Sun, 31 Aug 2008 09:05:27 +0200

Joseph Garvin wrote:

> To shrink my plugin size I'm trying to convert my sound samples to be
> 22050hz instead of 44100. But when I do this the sound always plays too
> fast like a chipmunk. I'm calling pcm_set_frequency(22050) but no matter
> what number I give it (I tested crazy values like 100) I get the same
> result. It always tries to play at 44100hz. I'm trying on the Sansa e200
> simulator. Is this a limitation of the simulator or maybe of the e200?
> If so it'd be nice to get some sort of console warning.

pcm_set_frequency sets the frequency of the hardware, but it is usually
quite limited in what frequencies it supports. Try dsp_configure, using
DSP_SWITCH_FREQUENCY, to set the frequency. See the mpegplayer audio
thread for an example.

Received on 2008-08-31

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