[PD] equalizers

[Linium]

Le Sun, 27 May 2001, Juha Vehviläinen a écrit :
> This might be obvious, but how do I create equalizers with pd?
> 
> thanks,
> j


It depends what kind of EQ you need.
EQ are in fact various kind of filters. Of course we should not forget the
interface.  

For the filtering issue:

You have the biquad~ raw filter that let you implement all sort of EQ. Let see
the "ggee" package since it provides some abstractions to
get easily shelving filter, band pass and other kind of EQ from biquad~.

In the pd "Help" you have some fft examples as well for more advanced filtering.

You may get the iemlib library since there is a fair choice of nice
filters and some graphical object as well to make interfaces (sliders, vu meter, etc).

If you run linux you can try LADSPA plugins for again more stuff.

http://www.pure-data.org to find all theses libs.

For the interface :

It is more difficult to answer.
Pd has some objects to do graphical stuff (drawcurve, drawpolygon) but I don't
know if it stable, Miller seems still working on them.

Ggee and iemlib provide some sliders that will let you implement EQ like  
multiband ones.

On the other hand since it is possible to draw with the mouse in the graphic of
an array (when its size allow to see one pixel for one point in the array) you
could use the resulting curve to affect value to the bands of your filter.    
It should be nice with a fft filter... a graphical equalizer ! :)

Best regards,

Linium