[PD] Input Controllers for Pd with finer grain than MIDI

[Miller Puckette]

HI all,

Sorry for the belated reply...

Here's a dejitter algo I use on sliders, joysticks, etc...  You choose
a constant jitter amount and essentially build a loose steering
linkage.  Call the constant JITTER, and do the following (in pseudo-code):

if (input > last-output + JITTER)
	last-output = input - JITTER

else if (input < last-output)
	last-output = input

... then output the new "last-output", possibly filtering out repetitions
of the same value.  You can do this in Pd using "moses" objects, for
instance.  Note that the output range is the input range minus JITTER,
so if it's MIDI and JITTER is one, the output will be 0-126.

cheers
Miller

On Fri, May 31, 2002 at 09:11:16AM +0100, Rory Walsh wrote:
> Hi David I'm not sure I understand what you mean but
> are you talking about values jumping all over the
> place from one minute to the next? I have this problem
> when I use Midi sliders, for instance the the midi
> values will often jump three values each time I move
> the midi slider, if this is what you talking about I
> just use a line object to help it move smoothly to the
> next value without missing the values in between, is
> that any help?
> 
> ROry.
> 
>  --- David McCallum <8dngm at qlink.queensu.ca> wrote: > 
> >          I was toying around with using lop~ to
> > reduce jitter and it didn't 
> > really seem to do much. Do you have any suggestions
> > as to what settings I 
> > should be setting the lop~ to, or is there anything
> > else I should be doing 
> > to it? I compared the results of the straight output
> > against the output of 
> > the lop~ (with snapshot~) and all I found was that
> > with higher cutoffs of 
> > the lop~ the decimals of the values seemed to
> > disappear (but I think this 
> > probably isn't anything worth noting), but they both
> > seemed to jitter as much.
> > 
> >          Any suggestions?
> > 
> > At 04:49 PM 25/05/2002 -0700, Andrew (Andy) W.
> > "Schmeder wrote:
> > > > I built a controller that uses the joystick port
> > (spacetaxi.de)
> > > > but the jitter is a little too much to deal with
> > (unless anyone has a
> > > > jitter-filter patch they could send me).
> > >
> > >To reduce jitter on a joystick I use joystick-value
> > -> sig~ -> lop~.
> > >There is no loss of information assuming that the
> > jitter is faster than
> > >you can physically move the joystick.
> > >
> > >
> > >andy
> > 
> > .
> > . David McCallum
> > . Queen's University Electronic Music Studio Manager
> > .         and Noise Maker
> > . html://mentalfloss.ca/sintheta/
> > .
> > 
> >  
> 
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