[alsa-devel] trace PCM data from usb bus to alsa lib

[ZeroCluo]

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" .


Zero