[alsa-devel] Create a stereo sound with alsa

[Clemens Ladisch]

Luca Longhi wrote:
> Hi. I've written a code to play two different sine wave (same amplitude and
> f1=440Hz f2=600Hz) one on the left channel and the other on the right
> channel. It seems to be working. I've tried doing the same thing using two
> different sounds file (stereo) but the result is wrong.

>   err=snd_pcm_hw_params_set_format(handle, params, SND_PCM_FORMAT_S16_LE);	//16bit per campione=2byte per campione
>     ...
>     char * buffer1;
>     char * buffer2;
>     char * risultato;
>     ...
> 		{v1=buffer1[j1];}
> 		{v2=buffer2[j2];}
> 		risultato[i++]=v1;
> 		risultato[i++]=v2;

The device expects 16-bit samples, but you write 8-bit values.


Regards,
Clemens