On 14 April 2014 09:42, Tanu Kaskinen <tanu.kaskinen at linux.intel.com> wrote: > On Mon, 2014-04-14 at 01:16 +0200, Lukasz Marek wrote: > > Hi, > > > > I hope this is correct list for general questions about PulseAudio > > development. I devel some stuff for FFmpeg project and I want to update > > pulse output device. I have few questions: > > > > - Is this possible to detect that mute/volume for sink input has changed > > without calling pa_context_get_sink_input_info periodically? > > I saw some commits recently that seems to add this, but ubuntu still use > > 4.0 for example, so probably not, but I still wanted to ask about it. > > You can get notifications about sink input changes with the subscription > API: http://freedesktop.org/software/pulseaudio/doxygen/subscribe.html > > The API will tell you only that something changed (not necessarily > volume/mute), so when you get a change event for a sink input that you > are interested in, you then call pa_context_get_sink_input_info(). Looks like something I needed. Thanks. > > - pa_stream_write has parameter pa_free_cb_t to provide zero-copy. > > Unfortunately it doesn't accept user data, in case of FFmpeg, the buffer > > is inside AVBuffer, AVPacket, or AVFrame (AVBuffer technically). > > Each of them contains a variable with a buffer that should be passed to > > pa_stream_write, but free function should unref this structure, not > > buffer itself. > > It cannot be extracted without copying and this zero-copy is hard to > reach. > > My question is: do you think it is doable/acceptable to add other > > function that would accept userdata for free callback? > > I know there is pa_stream_begin_write, but this is not suitable neither. > > Yes, I think that would be acceptable. I wonder what would be a good > name for the function. pa_stream_write_with_free_userdata? > Maybe: typedef void (*pa_free_ext_cb_t)(void *p, void *userdata); pa_stream_write_with_free_ext(...) I'll try to prepare a patch soon. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20140414/61546c4d/attachment.html>
