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Sophisticated dynamic filter

Started by sdsp January 3, 2006
Hi
I need to create a software dynamic digital filter running in windows XP
with those characteristics:

When the input level goes over the threshold, after a delay, the filter
become active.

When the input level returns under the threshold, the filtering in
disabled after an other delay.

The best situation would be to have a graphic equalizer filter, but a
filter boosting highest frequencies is an acceptable solution.
I work with stereo digital input sampled at 96 kHz � 24 bit, 10 � 15 min.
each.

I�ll prefer to use free software(!), if this is not too complicated to
use. 

I�ve no realtime requirement.
Instead it�s preferable storing the output directly in digital format.

As you can understand form my lexicon, I�ve no experience in digital
filtering; anyway I�ve no difficulties in learning a new language.


Thanks an advance.




sdsp wrote:
> Hi > I need to create a software dynamic digital filter running in windows XP > with those characteristics: > > When the input level goes over the threshold, after a delay, the filter > become active. > > When the input level returns under the threshold, the filtering in > disabled after an other delay. > > The best situation would be to have a graphic equalizer filter, but a > filter boosting highest frequencies is an acceptable solution. > I work with stereo digital input sampled at 96 kHz � 24 bit, 10 � 15 min. > each. > > I�ll prefer to use free software(!), if this is not too complicated to > use. > > I�ve no realtime requirement. > Instead it�s preferable storing the output directly in digital format. > > As you can understand form my lexicon, I�ve no experience in digital > filtering; anyway I�ve no difficulties in learning a new language. > > > Thanks an advance.
What do you want the filter to accomplish when it's active? Jerry -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
>sdsp wrote: >> Hi >> I need to create a software dynamic digital filter running in windows
XP
>> with those characteristics: >> >> When the input level goes over the threshold, after a delay, the
filter
>> become active. >> >> When the input level returns under the threshold, the filtering in >> disabled after an other delay. >> >> The best situation would be to have a graphic equalizer filter, but a >> filter boosting highest frequencies is an acceptable solution. >> I work with stereo digital input sampled at 96 kHz � 24 bit, 10 � 15
min.
>> each. >> >> I�ll prefer to use free software(!), if this is not too complicated to >> use. >> >> I�ve no realtime requirement. >> Instead it�s preferable storing the output directly in digital format. >> >> As you can understand form my lexicon, I�ve no experience in digital >> filtering; anyway I�ve no difficulties in learning a new language. >> >> >> Thanks an advance. > >What do you want the filter to accomplish when it's active? > >Jerry >-- >Engineering is the art of making what you want from things you can get. >�����������������������������������������������������������������������
Hi Jerry, Thank you for your attention. Basically I need to attenuate low frequencies and to exalt hi frequencies. The best would be to filter the frequencies in group of 1/6 octave. In the past days a new requirement arose, and I also need realtime processing (but it�s good just to resolve the first problem). Stephen
sdsp wrote:

> Hi Jerry, > Thank you for your attention. > Basically I need to attenuate low frequencies and to exalt hi > frequencies. > The best would be to filter the frequencies in group of 1/6 octave. > In the past days a new requirement arose, and I also need realtime > processing (but it's good just to resolve the first problem).
You might be interested in a dynamic audio equalizer like it is described here (PDF, 666kB): http://www.weiss.ch/documents/brochureEQ1-DYN.pdf Regards, Andor
>sdsp wrote: > >> Hi Jerry, >> Thank you for your attention. >> Basically I need to attenuate low frequencies and to exalt hi >> frequencies. >> The best would be to filter the frequencies in group of 1/6 octave. >> In the past days a new requirement arose, and I also need realtime >> processing (but it's good just to resolve the first problem). > >You might be interested in a dynamic audio equalizer like it is >described here (PDF, 666kB): > >http://www.weiss.ch/documents/brochureEQ1-DYN.pdf > >Regards, >Andor >
Tih is a realy very intresting device, but I need a sofwrare solutios for my application. Thanks Stephen