'Twas brillig, and Colin Guthrie at 19/11/10 11:33 did gyre and gimble:
> 'Twas brillig, and Tsai Yu-Chin at 19/11/10 02:29 did gyre and gimble:
>> Thank you for your help.
>> I refer to source code of pavucontrol and I program a simple code below:
>
> Ultimately what your code is doing is thus:
>
> 1. Get the Sink Index the stream is using.
> 2. Get the Monitor Source for the Sink.
> 3. Record from the Monitor of the Sink.
>
>
> The sink monitor will contain the product of *all* streams playing on
> the sink. There is a special "Sink Input Monitor" that you can connect
> to for your recording. It's will just contain the sound for the Sink
> Input itself. You still need to get the Monitor for the sink to which
> your stream is attached, but you pass this in to the
> pa_stream_connect_record function as a string.
>
> In pavucontrol's mainwindow.cc see the method:
> MainWindow::createMonitorStreamForSinkInput()
>
For clarity, the code below is NOT from the above function. I meant to
include some text saying "so you could write something like this:" here :)
> int sink_input_index = ?; /* You should have this value already in your
> code */
> int sink_monitor_source_index = ?; /* You should have this value already
> in your code */
> char dev[16];
> pa_stream *stream;
>
> /* assume variable "ss" is your sample spec and "attr" is your buffer
> attributes */
>
> if (!(stream = pa_stream_new(context, _("Single Radio Snooper!"), &ss,
> NULL))) {
> /* ERROR */
> return;
> }
>
> /* Put the source which we'll record here (i.e. the montior of the sink
> the stream is playing on) */
> dev = snprintf(dev, sizeof(dev), "%u", sink_monitor_source_index);
>
> /* restrict the recording to just one monitor stream */
> pa_stream_set_monitor_stream(stream, sink_input_index);
>
> /* Set callbacks */
> pa_stream_set_read_callback(stream, ....);
> pa_stream_set_suspended_callback(stream, ....);
>
> if (pa_stream_connect_record(stream, dev, &attr, (pa_stream_flags_t)
> (PA_STREAM_DONT_MOVE|PA_STREAM_ADJUST_LATENCY)) < 0) {
> /* ERROR */
> pa_stream_unref(stream);
> stream = NULL;
> return;
> }
>
>
>
> Obviously if the user moves your stream to another device you have to
> tear down and recreate your stream against the new monitor source. Not
> ideal, but should be fine in most circumstances. Sadly there isn't a way
> to record the radio fully across device moves as far as I know...
> although perhaps not setting the PA_STREAM_DONT_MOVE flag will allow the
> record stream to automatically move if the stream is moved? I don't know...
>
> HTHs
>
--
Colin Guthrie
gmane(at)colin.guthr.ie
http://colin.guthr.ie/
Day Job:
Tribalogic Limited [http://www.tribalogic.net/]
Open Source:
Mageia Contributor [http://www.mageia.org/]
PulseAudio Hacker [http://www.pulseaudio.org/]
Trac Hacker [http://trac.edgewall.org/]
