Month: September 2013

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Adam Rokhsar’s Max frame subtraction example

Uses video frame subtraction in jitter to control playback of audio clip.

download

https://github.com/tkzic/max-projects

folder: frame-subtraction

patch: frameSubtraction_example.maxpat

You will also need an audio file: aiff, wav, etc., to load into a Max buffer.

dependencies

You will also need the cv.jit library (computer vision): http://jmpelletier.com/cvjit/

Add the location of these files to your path in Max using Options | File Preferences.

Note: When I loaded the patch in Mac OS 10.8 – the computer automatically downloaded and installed Java updates.

instructions

  • Load an audio file for playback
  • Try setting minimum summed pixels to 150,000 or less for greater effect – depending on amount of light in the room
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Send Tweets with a Little Tikes piano

This project uses the Max fzero~ object to detect which key of the piano gets pressed and send a pre-written Tweet like “Signs point to yellow” based on the color of the key.

It works with the Internet sensors project that sends Tweets from Max using Ruby. https://reactivemusic.net/?p=7013

download

https://github.com/tkzic/internet-sensors

folder: twitter-ruby

instructions

  1. Follow instructions here to send Tweets using Max and Ruby: https://reactivemusic.net/?p=7013
  2. At this point you will have a Max patch open and a Ruby server running in a terminal window.
  3. Now open little-tikes.maxpat
  4. Carefully play individual tones on the Little Tikes piano. 

notes

fzero~ is probably not the best choice for this. It doesn’t work above 2500hz which means it won’t probably distinguish between the lowest and highest key which are an octave apart. In fact the Little-Tikes piano, for a pitched instrument, is difficult to analyze. Due to relatively equal weight of partials to fundamental, and the quick decay. Other choices, would be pitch~ (Jehan) fiddle~ (Pucket…)

I remember seeing an Arduino project where somebody did this in reverse – actually built a motorized striker to play the piano)

… insert link to video here…