Author Topic: Looking for a simple C++ function for lowpass Butterworth filter  (Read 14392 times)

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Offline jsmokerTopic starter

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As stated in the subject, I'm looking for a simple C++ function for lowpass Butterworth filter.  I have 16 x 12 bit inputs coming into the computer but they're very jumpy. 

Thanks,
Jason

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Re: Looking for a simple C++ function for lowpass Butterworth filter
« Reply #1 on: July 23, 2007, 06:18:33 PM »
You only ask the hard questions . . .

Anyway, wikipedia gives a 3rd order equation derived for you. Shouldnt be hard to write your own C++ with that:
http://en.wikipedia.org/wiki/Butterworth_filter#A_simple_example

I havent done this stuff in ages, I dont really understand it anymore  :-[

This is potentially useful:
http://www.daycounter.com/Filters/LC-Butterworth-Filter/LC-Butterworth-Filter-Calculator.phtml

A google search came across a lot of source code, just none in C++
http://www.google.com/search?hl=en&rls=DGUS%2CDGUS%3A2006-11%2CDGUS%3Aen&q=%22low+pass+Butterworth+filter%22+code

 


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