[gst-devel] volume plugin with dparams

Baker, Steve SBaker at CHELLO.com
Thu Nov 15 07:49:02 CET 2001

> > Is anyone working on adding dparams to volume?

The volume plugin looks very trivial to dparamise using the callback method
of updating the param.  See sinesrc for an example of a dparams based plugin
which can control its volume.

> I'm still a little fuzzy on
> dparams myself, esp in the context of a live application.  steveb, you
> have any comments?

dparams really come into their own in a non-live app, but it can still add
value to a live app. The dparams lib would be a good place to implement the
- mapping logarithmic values to linear ui controls (done)
- implementing smoothing so that rapid value changes don't cause audible
discontinuities (done)
- saving a session of knob-twiddling for later playback
- creating dparams which change their value according to some function (LFO,
ramps, etc)

> > Any work on some kind of sequencer to record stream changes 
> and dparam
> > values?
> Can you elaborate a little more on what you mean by this?

I presume you would like to save the control actions from a live performance
for later playback and manipulation.  The dparams layer would be the right
place to implement this but I haven't yet worked out the details of how this
would be done (MIDI may be part of the picture here but not the only part).


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