Hi Lennart, >Note that only very few audio devices actually have independant >headphone and speaker volumes. PA supports different mixer paths by >means of the device port functionality, but you may not assume that a >particular path is available. Also, PA will not allow you to control >the volume of a path that is currently not active. The reason for that >is that this is often not even possible since multiple paths might not >be independant of each other. Understood. One question re headphone operation - when is jack-sensing expected in PA ? >If you want to control this the best way is probably to write a little >module that lives inside of PA and can flag this synchrnously instead >of doing that out-of-process asynchronously. Would hope to get around to doing this in the near future. Time or lack of being the only factor ... Will get back to you on this. >I'd be happy to merge a patch that would treat >pa_context_set_sink_mute_by_index() with an index of PA_INVALID_INDEX >as a request to mute all sinks, and similarly for sources. That would be very useful for me. thanks. >muting and volume changing is orthogonal. PA treats them completely >indendantly. (Note however that some client programs do apply some >connection here: i.e. gnome-volume-control mutes the device if you >pull the volume to minimum) >PA_VOLUME_NORM really means max hw amplification. As tanuk pointed >out >the 0dB value of the hw is at the "base" volume. And if you want >digital amp you can even go > PA_VOLUME_NORM which is even louder. Understood. Thanks for the clarifications. Conor On Wed, Jan 13, 2010 at 7:56 PM, Lennart Poettering <lennart at poettering.net>wrote: > On Tue, 12.01.10 11:48, Forwind info (forward at forwind.net) wrote: > > A few comments on top of those tanuk already provided: > > > 1. To obtain the volume of primary Output Device. > > ans: Fetch the sink info via pa_context_get_sink_info_by_index(). The > > return value will contain volume data type (pa_cvolume). > > > > 2.Differentiate between headphone volume if plugged in and speaker volume > > ans: Detect headphone connection - PulseAudio intend to expose > > jack-sensing once it becomes available to them from below. Its in the > > pipeline apparently. I need to do some more investigation around this. > Some > > devices expose individual headphone volumes as opposed to speaker volumes > > others don't. > > Note that only very few audio devices actually have independant > headphone and speaker volumes. PA supports different mixer paths by > means of the device port functionality, but you may not assume that a > particular path is available. Also, PA will not allow you to control > the volume of a path that is currently not active. The reason for that > is that this is often not even possible since multiple paths might not > be independant of each other. > > > 4. If the sound is muted and some exterior application attempts to play > > sound then flag it > > ans: Subscribe to the PA_SUBSCRIPTION_EVENT_SINK_INPUT event and on > the > > callback check to see if that sink is muted (boolean). Note if the client > > application is paused, the sink is then muted and the client app is > restart > > the event will not be triggered. This might be not satisfy UI spec > > requirements. Check with MPT. > > If you want to control this the best way is probably to write a little > module that lives inside of PA and can flag this synchrnously instead > of doing that out-of-process asynchronously. > > > 5. Ability to mute all output sinks. > > ans: pa_context_set_sink_mute_by_index()- iterate through all sinks > > returned via pa_context_get_sink_info_list(). Maybe there is a > mute > > all switch - could not see it in the docs right now - will ask on #pa on > > freenode. > > I'd be happy to merge a patch that would treat > pa_context_set_sink_mute_by_index() with an index of PA_INVALID_INDEX > as a request to mute all sinks, and similarly for sources. > > > 6. Unmute all outputs and return to previous volumes. > > ans: PA's module-stream-restore - more investigation. Apparently this > > will store previous volumes of all sinks and restore them when required. > > muting and volume changing is orthogonal. PA treats them completely > indendantly. (Note however that some client programs do apply some > connection here: i.e. gnome-volume-control mutes the device if you > pull the volume to minimum) > > > 8. Set individual outputs volumes to max. > > ans: Set the sink (output device) in question to PA_VOLUME_NORM. > > pa_cvolume_reset() - should do this for the sink in question. > > PA_VOLUME_NORM roughly corresponds to 0DB => MAX volume without clipping. > > PA_VOLUME_NORM really means max hw amplification. As tanuk pointed out > the 0dB value of the hw is at the "base" volume. And if you want > digital amp you can even go > PA_VOLUME_NORM which is even louder. > > Also see: > > http://pulseaudio.org/wiki/WritingVolumeControlUIs#Volumes > > Lennart > > -- > Lennart Poettering Red Hat, Inc. > lennart [at] poettering [dot] net > http://0pointer.net/lennart/ GnuPG 0x1A015CC4 > _______________________________________________ > 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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