From mboxrd@z Thu Jan  1 00:00:00 1970
From: Takashi Iwai <tiwai@suse.de>
Subject: Re: trace PCM data from usb bus to alsa lib
Date: Wed, 17 Jun 2009 10:01:10 +0200
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To: ZeroCluo <Zero.CLuo@gmail.com>
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At Wed, 17 Jun 2009 07:25:25 +0000 (UTC),
ZeroCluo wrote:
> 
> Hi 
> 
>   I am trying to trace the Audio data from usb bus.
> in kernel: 
> dump data in retire_capture_urb() ,found data format is like:
> AABB 0000 CCDD 0000 ;
> 
> but in alsa library ,
> dump data in snd_pcm_mmap_begin(),the "0000" is cut,only "AABB CCDD",
> 
> Do you know when and where those "0000" is cut?

Are you using the native format that the hardware runs?


Takashi