[alsa-devel] trace PCM data from usb bus to alsa lib
tiwai at suse.de
Wed Jun 17 17:52:22 CEST 2009
At Wed, 17 Jun 2009 08:33:15 +0000 (UTC),
> Takashi Iwai <tiwai <at> suse.de> writes:
> > At Wed, 17 Jun 2009 16:10:26 +0800,
> > Zero Luo wrote:
> > >
> > > Dear Takashi,
> > >
> > > Data from usb dongle is 16K*16 bit PCM data.
> > And what is the format and channels you are using in alsa-lib?
> > alsa-lib itself can convert formats and channels automatically if needed.
> > Takashi
> In alsa-lib ,I set data format as 8K * mulaw .
> hwparams.format = SND_PCM_FORMAT_MU_LAW;
> hwparams.rate = 8000;
> hwparams.channels = 1;
> Yes,indeed alsa-lib help to convert formats.But before alsa-lib convert pcm
> data to mulaw,I dumped the src data in snd_pcm_mulaw_encode() which already
> has no "0000" .
Well, another question is whether the output result is correct.
Did you get broken output or so?
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