Hi, 'Twas brillig, and Peter Kornatowski at 10/07/09 17:51 did gyre and gimble:
I have a following problem: I have a debian lenny system with a PCMCIA voicecard (Sierra Wireless, to which I can directly connect a wired headset) with a 2G SIM card. Making calls to other phones works fine. But I want to use my bluetooth headset (Jabra BT530) for the calls. I connect the headset through Pulseaudio (with module-bluetooth-device). Making SIP-calls with it (with Twinkle, not over the voicecard) works fine. I have a cable for the voicecard so I can connect it to the line in and line out of the soundcard. Now I would have to somehow route the bluetooth headset source to the soundcard (alsa) sink and the alsa source to the headset sink, so that I could "speak" to the voicecard and get speech from it to the bluetooth headset. I tried move-sink-input, but this just moves the output of a sink to another sink. Also all other commands and modules of Pulseaudio seem like they would not do the trick. Does someone of you have any ideas? Do I have to use another program? If yes, which one?
Do you know I think this is probably the very first real world example of where connecting sources->sinks (and vice versa) is desirable!
The problem comes with differing clocks. The two devices you're connecting together cannot be directly connected as their clocks will not be perfectly in sync. It's the same problem you'd get if you tried to join two car engines together and drive the same wheels! The different speeds of the engines would eventually break your drive system.
So you really need an active process that will be able to dynamically resample (drop samples or synthesize new ones) the data to ensure that two devices stay in sync.
Now pulseaudio does have some of the code to do that already in the form of module-compbine-sink. It is able to create a virtual sink and which really outputs to multiple real sinks. In order to do that it has to take care of all that resampling jiggery pokery.
But the sort answer is that, "no" there is no way to connect sinks->sources or sources->sinks in this way as things stand. It will likely happen at some point in the future, but I'm not sure if there is a solid plan.
In the mean time, there is a very dodgy and hacky thing you can do which is to to use "parec | pacat" (with appropriate arguments to select source/sink) and a corresponding "pacat | parec".
This does not handle any of the clock stuff so will likely yield unsatisfactory results, but it may allow you to play a bit for now.
Cheers Col -- Colin Guthrie gmane(at)colin.guthr.ie http://colin.guthr.ie/ Day Job: Tribalogic Limited [http://www.tribalogic.net/] Open Source: Mandriva Linux Contributor [http://www.mandriva.com/] PulseAudio Hacker [http://www.pulseaudio.org/] Trac Hacker [http://trac.edgewall.org/] _______________________________________________ pulseaudio-discuss mailing list [email protected] https://tango.0pointer.de/mailman/listinfo/pulseaudio-discuss
