[LAD] ALSA FLoat sample format

Erik de Castro Lopo mle+la at mega-nerd.com
Thu Aug 16 07:52:20 UTC 2007

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Predrag Viceic wrote:

> For some unknown reason, I seem to be unable to set SND_PCM_FORMAT_FLOAT 
> format flag when initialising alsa driver. This happens with my both cards 
> (on is the laptops AC'97 Audio Controller and the other a similar onboard 
> cart)
> This line used to work with alsa 0.9 but return an "Invalid argument" error 
> with alsa 1.0.14a :
> snd_pcm_hw_params_set_format(alsa_pcm_handle, alsa_hwparams, 

You probably want SND_PCM_FORMAT_FLOAT (without the _LE at the end)
to specify CPU native float. Using SND_PCM_FORMAT_FLOAT_LE will mean
that your code is almost certain not correct for big endian CPUS.

> Example code at lines 1031-1041 :
> http://cvs.savannah.nongnu.org/viewvc/freecycle/src/soundplayer.cpp?annotate=1.19&root=freecycle

That should probably be fixed as well.

Erik de Castro Lopo
"These are the finest moments in (post)modern life, when satire is completly
indistinguishable from reality... I usually have to rely on the presidential
elections for such dada." -- frenomulax on Jesux a christian Linux distro.

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