and test .wav file is at <a href="http://gamma.cs.unc.edu/SOUNDC/Assignments/clapping!_2.wav">http://gamma.cs.unc.edu/SOUNDC/Assignments/clapping!_2.wav</a><br><br><div class="gmail_quote">On Mon, Oct 26, 2009 at 5:50 PM, Drip Stone <span dir="ltr"><<a href="mailto:dripstone.blendercn@gmail.com">dripstone.blendercn@gmail.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><div class="im">Hello again,<br><br>I obtain data for fbuffer in following way:<br> char *fbuffer = ( char * ) malloc ( 10240000 ); //10M bytes<br>
long length = fread ( fbuffer, 1, 10240000, file );<br><br>I also set alsa in float mode:<br>
snd_pcm_hw_params_set_format ( handle, params,<br> <div> SND_PCM_FORMAT_FLOAT_LE );<br><br>I pasted all the code at <a href="http://pastebin.com/m7fdf0957" target="_blank">http://pastebin.com/m7fdf0957</a>.<br>
<br><br>Thank you,<br>Dripstone<div><div><span><br></span></div></div></div><br><br></div><div class="gmail_quote"><div class="im">On Mon, Oct 26, 2009 at 3:59 PM, Jens M Andreasen <span dir="ltr"><<a href="mailto:jens.andreasen@comhem.se" target="_blank">jens.andreasen@comhem.se</a>></span> wrote:<br>
</div><div><div></div><div class="h5"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">Nothing in the posted code fragment suggests that neither in nor out is<br>
remotely related to floats. Where do you get yor in-data from? Why is<br>
fbuffer[] a bytearray (if that is what it is?) How was ALSA opened?<br>
<font color="#888888"><br>
<br>
/j<br>
</font><div><br>
On Mon, 2009-10-26 at 15:05 -0700, Drip Stone wrote:<br>
<br>
</div><div><div></div><div>> while ( 1 )<br>
> {<br>
> for ( int i = 0; i < frames; i++ )<br>
> {<br>
> float t = 0;<br>
> if ( left ) //for left channel<br>
> {<br>
> t = *((float*)&(fbuffer[pos+i*4])); //4 bytes each<br>
> frame<br>
> t*=2;<br>
> //printf("%f ",t);<br>
> for ( int j = 0; j < 4; j++ )<br>
> buffer[i*8+j] = ((char*)&t)[j]; //8 bytes for 2<br>
> channels<br>
> }<br>
><br>
> rc = snd_pcm_writei ( handle, buffer, frames );<br>
> pos += frames * 4;<br>
> }<br>
><br>
> I think the value is not out of [-1.0,1.0]. BTW, what does it mean<br>
> when a value is negative?<br>
><br>
><br>
> Best,<br>
> Dripstone<br>
><br>
> 2009/10/26 Jörn Nettingsmeier <<a href="mailto:nettings@folkwang-hochschule.de" target="_blank">nettings@folkwang-hochschule.de</a>><br>
> On 10/26/2009 11:38 AM, Victor Lazzarini wrote:<br>
> > Well if the audio was clipped, there would probably be some<br>
> audible<br>
> > distortion.<br>
> > Perhaps if a code fragment was posted we could give a more<br>
> informed<br>
> > opinion.<br>
><br>
><br>
> i was thinking of operating on files, where clamping can be<br>
> done with<br>
> perfect fidelity. but i may have misunderstood the OP.<br>
><br>
><br>
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><br>
><br>
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<br>
</div></div></blockquote></div></div></div><br>
</blockquote></div><br>