[PD] signal weighted median filtering

Hans-Christoph Steiner hans at eds.org
Sat Jul 21 19:22:03 CEST 2007

Just going thru old list emails that I missed.  This is interesting,  
it seems to work pretty well.  It would be nice to see it compared to  
other techniques and using other input signals.  I quickly added a  
lop~ for comparison:

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On May 26, 2007, at 2:02 AM, Andy Farnell wrote:

> Nice. The graph says it all, it really snuffs out those spikes.
> Yeah, and it eats way too much CPU, but I enjoy the instructional
> value of seeing this filter done as signal expressions.
> Andy
> On Fri, 25 May 2007 14:01:21 -0500
> "Charles Henry" <czhenry at gmail.com> wrote:
>> Hi, list,
>>   I've created an abstraction for performing weighted median  
>> filtering
>> on a signal using 5 coefficients.  It's a real cpu hog.  It uses
>> heavily the expr, expr~ and fexpr~ externals, which leads to some
>> redundant calculations on each sample.
>>   The test patch enclosed shows how effective this can be for  
>> removing
>> impulsive noises from a signal (like the pops on a record).
>> Chuck
> -- 
> Use the source
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