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Determining high, medium, low frequency range of sample audio.

July 22, 2011 | 6:12 pm

How can I root out the high, medium, and low frequencies of an audio sample. I want to turn those three frequency ranges into Data and use it to manipulate videos. I know you can do something like this with Vizzie but I want to record both video and audio. Unfortunately the Followr (Vizzie) object doesn't connect to jit.vcr so I'm trying to make a custom patch that works similar to Followr but I could connect to jit.vcr for recording.

(I'm still kind of new to this and programming in general)

[attachment=167134,2461]

Attachments:
  1. vizzie.tiff

July 23, 2011 | 7:47 pm

There are many ways. Basically you want to split the audio into N (in your case, 3) separate signals, each filtering out a particular range. There are various filters that chop away various frequency ranges, in your case you could do this with a lowpass (keep frequencies below X hertz), a band pass (keep frequencies around X hertz, with a band witdth of W), and a high pass (keep frequencies above X hertz). You could do this with 3 filtergraph~ + biquad~ objects; OR with a lowres~ and reson~ objects.
Turning that into "Data" is a more complicated matter, depending on what type of data you want: pitch/amplitude/rhythmic attacks/etc. If you don’t know how to code these, one place to start is the external object "analyzer" which combines various analysis routines to turn signals into discrete data.
Dan


July 23, 2011 | 11:12 pm

Have a look at [ffb~] for the audio splitting.


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