[theora-dev] Volume control in Cortado

[ogg.k.ogg.k at googlemail.com]

> Is there a way to control the volume in Cortado?  It seems that the default
> volume for audio is way too high and I can't see any way to control it.

No.

> If not present, how difficult would it be to add a volume control to
> Cortado?

Probably rather easy. I see two main ways to do it:
- add a 'volume' property to the audio sinks, and pass it to the
relevant Java sound
- add a 'volume' element which scales PCM data, and insert it before
the audio sink

The latter is more generic, more gstreamery, and more work, though not
difficult.

A related task would be a way to control this via the UI. Maybe
clicking on the 'speaker; button could pop up a scrollbar similar to
the seeking one. There is a new callback for it, currently doing
nothing.