On Thu, 2011-02-03 at 14:35 +0200, Tanu Kaskinen wrote: > Hello, > > When we have a filter sink that does some processing, currently the > benefits of the flat volume feature are not really available. That's > because if you have a music player that is connected to the filter sink, > the hardware sink doesn't have any idea of the music player's stream > volume. > > In order to fix this, Pulseaudio 0.9.15 on Maemo 5 was hacked to > implement a feature that was dubbed "flat sink". The feature is still > needed in Maemo 6 / MeeGo, and now we are finally trying to get it to > upstream. The "flat sink" feature (better names welcome) works so that > the filter sinks that want to avoid the previously described problem > declare that they don't want to have independent volume, but they follow > the master sink volume instead. Then the volume logic is changed so that > the hardware sink calculates its real volume using also the streams > connected to the filter sink in addition to the streams that are > connected directly to the hardware sink. Basically we're trying to > create an illusion that from volume point of view all streams are > connected directly to the hardware sink, thus the stack of sinks > collapses into a "flat sink". > > I hope that sounds like something that can be merged to upstream. There > will be several patches, and I just sent the first. The rest of the > patches are not ready yet - I'll send them as I finish them. Update to the terminology: the "flat sink" feature shall be known as the "volume sharing" feature from now on. I think that's more descriptive, and doesn't get so easily mixed with the "flat volume" term. -- Tanu
