Re: [LAD] ALSA FLoat sample format

I am no alsa programming expert, but could it be that for some reason, alsa is attempting to open a hardware device (hw:0, or such) rather than a plugin device (such as plughw:0)? Or, perhaps it is opening the default interface, which is an alias for hw:0. This default could have changed between alsa versions.

Hardware devices will fail if an attempt is made to open them with anything other than parameters which are directly supported by the hardware. Plug devices however, will happly do things like convert sample rates and formats, at the cost of some uncertainty of what actually happens, and maybe some performance penalty. On Thu, Aug 16, 2007 at 09:39:48AM +0200, Predrag Viceic wrote: > Hi, > > > 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, > SND_PCM_FORMAT_FLOAT_LE) > > If I remove this line, the driver gets initialised but as integer sample > format, which, of course, generates noise as I'm sending 32bit floats to > the output... > > Example code at lines 1031-1041 : > http://cvs.savannah.nongnu.org/viewvc/freecycle/src/soundplayer.cpp?annot >ate=1.19&root=freecycle > > > Please, please help ! > > > Predrag > > http://freecycle.redsteamrecords.com