[PD] smoothing things ...

[IOhannes m zmoelnig]

Thoralf Schulze wrote:
> Hi everyone,
> 
> So, at the end of this lengthy post:
> - is there a possibility to amend Thomas' smoothing
> abstraction with a "set x"-message that would cause it
> to start interpolating from the x-value ? How
> demanding  (in terms of cpu cycles) would that
> abstraction then be?

i don't think that you can use soemthing like "set <f>" with dsp-filters.


> - if not: is there an easy-to-implement algorithm that
> does non-linear smoothing of yet-unknown parameters
> and detects parameter jumps? My math is a bit rusty,
> and googling only yielded stuff regarding the
> interpolation of _known_ values.

now that'll be cool: doing interpolation between (however yet) unknown 
values.
i guess this would solve many many problems.

a simple non-linear (IIR) low-pass filter is x[n]=a*x[n-1]+(1-a)*y[n]
(with 0<=a<=1)

however, this filter still only works for known values to filter.

apart from that, your problem is basically about unwrapping your 
incoming values [0..360] to something covering all values;
if you have a series that goes 0..89..188..267..356..85 you want it to 
become 0..89..188..267..356..445

attached is a file that unwraps degree-values.
it depends on zexy's [wrap] (because this was faster to do), but you can 
replace wrap with something build with [%].
the basic idea is to wrap the difference between to consecutive values 
and sum it up again.


mfg.a.sdr
IOhannes
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