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On Tue, Feb 28, 2012 at 03:30:24AM +0100, Frank Steinmetzger wrote: |
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> |
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> > dmix *may* be able to handle multiple audio streams (in practice, in |
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> > my personal experience, it always requires more work than PA); but it |
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> > will never be able to do the other stuff PA handles. |
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> |
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> This seems like a dumb question (for I was a strict PA denier until recently |
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> and have been using alsa-only since always), but does PA handle OSS |
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> applications better than alsa/dmix? Whenever I want to use sidplay, which only |
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> speaks OSS, I need to stop all other audio programs (e.g. press Stop in the |
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> Clementine player if it's only paused), or else /dev/dsp was busy. |
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PA doesn't care about oss (/dev/dsp). It opens the soundcard through |
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normal alsa interface (which means /dev/dsp becomes busy). You can |
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either kill pulseaudio, or tell pulseaudio to suspend the correspondig |
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sink (not sure what exactly happens if an audio stream through PA is active |
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etc..). |
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|
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Regarading oss (/dev/dsp) and plain alsa, it is the same, if something |
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opens the soundcard through alsa, /dev/dsp becomes busy... (even when |
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using dmix in alsa, because /dev/dsp is handled by a kernel modules, |
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dmix is userspace). |
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There is however a way to amke oss work with dmix through aoss (a small |
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program that preloads a binary, that 'hijacks' calls to open /dev/dsp |
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and 'reroutes' that to alsa, works most of the time, but can have |
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problems if the program does some weird things...) |
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In that case aoss opens the alsa device "pcm.dsp" (or dsp0, i'm not sure |
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right now), which you can easily point to dmix... |
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|
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from my /etc/asond.conf: |
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======================================== |
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pcm.dsp { |
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type plug |
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slave.pcm "duplex" |
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} |
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pcm.dsp0 { |
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type plug |
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slave.pcm "duplex" |
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} |
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pcm.!default { |
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type plug |
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slave.pcm "duplex" |
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} |
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pcm.duplex { |
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type asym |
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playback.pcm "dmix:0" |
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capture.pcm "dsnoop:0" |
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} |
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======================================== |
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|
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Then you can run (even multiple) 'aoss mpg123 file.mp3 ...' |
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You can also make this to work alongside pulseaudio, if you configure |
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pulseaudio to use the dmix device instead of directyly using the hw |
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device. |
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Nnote that this might cause problems, you have to disable pulseaudio's |
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autodetect and configure all soundcards manually, and using dmix |
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introduces some additional overhead and probles, also such setup is most |
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probably not supported by pulseaudio etc... However it also enables you |
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tu run plain alsa apps alongside PA (officialy you should just configure the |
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!default device to use the PA alsa plugin is simpler and it should work |
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better, though I had some problems with some apps) and more importantly |
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to run multi PAs simultaneusly (ie for multiple users...) |
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yoyo |
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