Playing always at half of the rate of recording.

Playing always at half of the rate of recording.

[超 李]

Hi All,
  I'm using alsa library to write an application that play and record audio 
at the same time. I openned the default pcm device twice, and set params for 
them, nonblock, RW_INTERLEAVED, S16_LE format, 8000Hz, and 1 channel, the 
only difference is using SND_PCM_STREAM_CAPTURE for recording, and using 
SND_PCM_STREAM_PLAYBACK for playing.
  But the bytes played are always near half of the recorded, and the sound I 
heard is slowed comparing with its normal speed.
  My enviroment are:
  RedHat 7.3 / alsa 0.9.0 rc5 / linux kernel 2.4.18-3
  sound card module: via82xx

  How can I solve this?
  Thanks!

Walter


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Re: Playing always at half of the rate of recording.

[Florian Bomers]

are you sure that sample size, number of channels and sample rate is the same for playback
and record?

Florian


"è¶ æ" wrote:
> 
> Hi All,
>   I'm using alsa library to write an application that play and record audio
> at the same time. I openned the default pcm device twice, and set params for
> them, nonblock, RW_INTERLEAVED, S16_LE format, 8000Hz, and 1 channel, the
> only difference is using SND_PCM_STREAM_CAPTURE for recording, and using
> SND_PCM_STREAM_PLAYBACK for playing.
>   But the bytes played are always near half of the recorded, and the sound I
> heard is slowed comparing with its normal speed.
>   My enviroment are:
>   RedHat 7.3 / alsa 0.9.0 rc5 / linux kernel 2.4.18-3
>   sound card module: via82xx
> 
>   How can I solve this?
>   Thanks!
> 
> Walter
> 
> _________________________________________________________________
> MSN 8 helps eliminate e-mail viruses. Get 2 months FREE*.
> http://join.msn.com/?page=features/virus
> 
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> your web site with SSL, click here to get a FREE TRIAL of a Thawte
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> Alsa-devel@lists.sourceforge.net
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-- 
Florian Bomers
Java Sound
Java Software/Sun Microsystems, Inc.
http://java.sun.com/products/java-media/sound/


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