I do agree that coding for pulse can be a steep learning curve, which is why I opted to build all my solutions by simply connecting to the text mode control socket and sending commands/parsing text output. I have built what is essentially a multiplex audio switch allowing any of x number input sources to play out of any x number of output sinks, all controlled via a python or php app. You should check out module-combine-sink. You could combine all your outputs, then simply mute all but the one you currently want to use. I am using this as a 4x4 switch for audio and it works great. I also have simple (but poorly commented) python/php source I am happy to share if it helps. Matt Nick Thompson wrote: > OK so I figured out the error of my ways, but I have to say this list > is pretty unresponsive in helping the community so I have to ask > myself "is pulse is a sensible choice for audio development today"? > Particularly since there is little in the way of useful setup > documentation for actually using the library on a programatic way, the > error messages from the library and utilities are not particularly > helpful and so on. > > What I need to be able to do is route audio around. I suspect write a > module for pulse that will look at the alsa stream class and based on > that use the input index to set the sick for that stream. It would be > nice to have a feature whereby I can rout all output sent to a > particular sink, to another sink. I guess what I'd like to do is be > able to create virtual devices whose output can be changed on the fly. > So for example I could define an mp3 output that I can switch between > headphone output and speaker output depending on a system setting. Or > between one speaker output and another. If pulse has a means to do > this already I'd appreciate someone pointing me in the direction that > can help. > > It seems ALSA will do most of this and the ALSA list seems to be a lot > more active, so maybe I was mistaken in thinking that Pulse would > really be a useful addition to our audio stack, particularly since on > an embedded system it consume disproportionate resources for the > benefit it provides. > > Also where is the mixer implemented and how is it controlled. Or is > the mixer just a dumb "you have 3 streams coming in and I will make > them one" type deal. In other words is there bussing or output > switching in the mixer. If not, is this planned? > > Anyway, in case this helps anyone else, the sources that are listed by > list-sources are not really sources to pulse. So trying to move them > around will not work. Here's something I wrote up on the subject: > > To see the output devices we have created use the list-sinks command > > > > >>> list-sinks > 2 sink(s) available. > * index: 0 > name: <usbAudio> > driver: <modules/module-alsa-sink.c> > flags: LATENCY HARDWARE > state: IDLE > volume: <0: 100% 1: 100%> > mute: <0> > latency: <97959 usec> > monitor source: <0> > sample spec: <s16le 2ch 44100Hz> > channel map: <front-left,front-right> > used by: <0> > linked by: <0> > module: <0> > description: <ALSA PCM on usbLexiconAlpha (USB Audio) via DMA> > index: 1 > name: <hdaAudio> > driver: <modules/module-alsa-sink.c> > flags: LATENCY HARDWARE > state: IDLE > volume: <0: 100% 1: 100%> > mute: <0> > latency: <75827 usec> > monitor source: <1> > sample spec: <s16le 2ch 44100Hz> > channel map: <front-left,front-right> > used by: <0> > linked by: <0> > module: <1> > description: <ALSA PCM on intelHDA (ALC883 Analog) via DMA> > > > > > Currently no sound is playing, so if you look to see the sink inputs, > you'll see that none have currently been created: > > > > >>> list-sink-inputs > 0 sink input(s) available. > > > > Play a file in a different terminal window (or using your preferred > method to make sound). For this experiment I used paplay: > > > > nick at nick-desktop:~$ paplay -v Sony\ CD-ROM\ Test\ Disk\ Type\ > 3.0/14\ Cantibile\ Op.\ 17.wav > Using sample spec 's16le 2ch 44100Hz' > Connection established. > Stream successfully created > > > > I used the -v option to get verbose output from the command, which has > no bearing on this experiment. > > Now if you look at the sink inputs you can see that one has been > created for the stream we are currently rendering. > > > > >>> list-sink-inputs > 1 sink input(s) available. > index: 9 > name: <Sony CD-ROM Test Disk Type 3.0/14 Cantibile Op. 17.wav> > driver: <pulsecore/protocol-native.c> > flags: > state: RUNNING > sink: <0> 'usbAudio' > volume: <0: 100% 1: 100%> > mute: <0> > latency: <500000 usec> > sample spec: <s16le 2ch 44100Hz> > channel map: <front-left,front-right> > resample method: auto > module: <3> > client: <7> 'paplay' > > > > > By inspection it can be seen that this stream is being rendered on the > "usbAudio" device. To switch this stream to the built-in audio source > is a straightforward operation, use the move-sync-input command in > pacmd. We can see from the output above that the stream index is 9 > (note that the index is incremented for each time a new stream is > created, so it has to be determined for each stream). > > > > >>> move-sink-input 9 hdaAudio > > > > Now if the sink inputs are listed again you can see the output sink > has changed, verifying this by listening, the output does indeed get > switched. > > > > >>> list-sink-inputs > 1 sink input(s) available. > index: 9 > name: <Sony CD-ROM Test Disk Type 3.0/14 Cantibile Op. 17.wav> > driver: <pulsecore/protocol-native.c> > flags: > state: RUNNING > sink: <1> 'hdaAudio' > volume: <0: 100% 1: 100%> > mute: <0> > latency: <500000 usec> > sample spec: <s16le 2ch 44100Hz> > channel map: <front-left,front-right> > resample method: auto > module: <3> > client: <7> 'paplay' > > > > > > The api routines for this are in the file > /pulseaudio-0.9.8/src/pulse/introspect.c > > Look at these routines: > > > > *int pa_stream_connect_playback (pa_stream *s,const char *dev, > const pa_buffer_attr *attr, pa_stream_flags_t flags, pa_cvolume > *volume, pa_stream *sync_stream)* > > / Connect the stream to a sink./ > > *int pa_stream_connect_record (pa_stream *s, const char *dev, > const pa_buffer_attr *attr, pa_stream_flags_t flags)* > > / Connect the stream to a source./ > *int pa_stream_disconnect (pa_stream *s)* > > / Disconnect a stream from a source/sink./ > > > > > > > On May 1, 2008, at 11:14 AM, Nick Thompson wrote: > >> Hi there, >> >> I have a system where I need to move sources to different sinks >> according to a policy. I thought I'd try this out using pacmd before >> I start trying to code this up with pulse, put pacmd does not behave >> as expected (by me :). >> >> I tried the following command in pacmd: >> >> >>> move-sink-input 0 hdaAudio.monitor >> No sink input found with this index. >> >> When I list the sinks and sources I get the output listed below. >> >> Is anyone familiar with pacmd. According to the help, this looks as >> if it should work. >> >> Eventually I want to publish several virtual devices, route them to a >> mixer (possibly via an SRC) and route the mixer output to a specific >> ALSA sink. I need two instances of mixers so that I can mix some >> streams to one output device and some streams to another. I need to >> be able to dynamically rout the entire output to another ALSA sink >> depending on the policy set. I'd also like to rout sources to the >> different mixer instances as required. If I can do routing within a >> single mixer instance, so much the better. Is Pulse capable of this >> or do I need to find another route to implement this. >> >> Thanks for any advice, >> >> Nick >> >> here is the output of list for sources and sinks: >> >> >>> list-sources >> 3 source(s) available. >> index: 0 >> name: <usbAudio.monitor> >> driver: <modules/module-alsa-sink.c> >> flags: >> state: IDLE >> volume: <0: 100% 1: 100%> >> mute: <0> >> latency: <0 usec> >> sample spec: <s16le 2ch 44100Hz> >> channel map: <front-left,front-right> >> used by: <0> >> linked by: <0> >> monitor_of: <0> >> module: <0> >> description: <Monitor Source of ALSA PCM on usbLexiconAlpha >> (USB Audio) via DMA> >> index: 1 >> name: <hdaAudio.monitor> >> driver: <modules/module-alsa-sink.c> >> flags: >> state: IDLE >> volume: <0: 100% 1: 100%> >> mute: <0> >> latency: <0 usec> >> sample spec: <s16le 2ch 44100Hz> >> channel map: <front-left,front-right> >> used by: <0> >> linked by: <0> >> monitor_of: <1> >> module: <1> >> description: <Monitor Source of ALSA PCM on intelHDA (ALC883 >> Analog) via DMA> >> * index: 2 >> name: <alsa_input.hw_0> >> driver: <modules/module-alsa-source.c> >> flags: HW_VOLUME_CTRL LATENCY HARDWARE >> state: IDLE >> volume: <0: 0% 1: 0%> >> mute: <0> >> latency: <23219 usec> >> sample spec: <s16le 2ch 44100Hz> >> channel map: <front-left,front-right> >> used by: <0> >> linked by: <0> >> module: <2> >> description: <ALSA PCM on hw:0 (ALC883 Analog) via DMA> >> >>> >> >> _______________________________________________ >> pulseaudio-discuss mailing list >> pulseaudio-discuss at mail.0pointer.de >> <mailto:pulseaudio-discuss at mail.0pointer.de> >> https://tango.0pointer.de/mailman/listinfo/pulseaudio-discuss > > ------------------------------------------------------------------------ > > _______________________________________________ > pulseaudio-discuss mailing list > pulseaudio-discuss at mail.0pointer.de > https://tango.0pointer.de/mailman/listinfo/pulseaudio-discuss > -------------- next part -------------- An HTML attachment was scrubbed... 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