[PD] jittering sensors

[Cesare Marilungo]

derek holzer wrote:

> If all the IRQ stuff that was just suggested doesn't make you happy, 
> try this:
>
> [sensor input]
> |
> [pack 0 n]     (where 'n' = the time in miliseconds you would like 
> your signal smoothed by)
> |
> [line]     (or [line~] if you are using it to control an audio signal]
> |
> [expr x]  (where 'x' is some math to get the numbers where you need them)
> |
> [whatever happens next]

This adds latency and results are still (albeit less) jumpy.

To smooth out a signal coming from a control (especially for midi ctls)
i use:

[input]
|
[sig~]
|
[lop~ n]         (try a n value between 20 and 50)
|
[whatever]

Found the trick above posted on this list by somebody else.

c.

>
> You could also explore [pow] or some of the other maths to do the job 
> of [expr] if you aren't a math whiz. The [line] object is really handy 
> to smooth out a jumpy signal. Try different values of interpolation 
> (i.e. the 'n' in the [pack] object), depending on how fast you need a 
> response versus how jumpy the input is. There used to be a [speedlim] 
> object that also did this nicely and was really designed for sensor 
> input, but the maintainer (Johannes Taelmann) doesn't seem to be 
> maintaining it (and has dropped off the face of the Earth as far as PD 
> in concerned unfortunately!).
>
> d.
>
>
> David Powers wrote:
>
>> Maybe I don't know what I'm talking about, but couldn't you just take 
>> the average value over some time period?
>>
>> ~David
>>
>> On 8/15/06, *patrick* < patrick at 11h11.com <mailto:patrick at 11h11.com>> 
>> wrote:
>>
>>     hi all,
>>
>>     i've done a project using the MULTIO of mamalala and HID to 
>> capture the
>>     output of my sensors (infra-red, tilt and such). sadly the values 
>> are
>>     really jittering and i have a logarithm sensor too.
>>
>>     i know that each case is unique, but maybe there's some rules to
>>     stabilize the fluctuation and correct the curve (logarithm)???
>>
>>     thanks for sharing any knowledge on this!
>>     pat
>
>


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