MIDI is a requirement if you want to do anything that includes synthesizing notes/sounds via external VST Plugins. This is one of the few add-ons that I found to be well documented and Windows compatible/tested. I plan to use it to talk to my DAW (Ableton Live) and produce sounds while interacting with the user using OF.
This plugin allows for Eulerian Video Magnification (EVM) which reveals temporal variations in a video stream impossible to see with the naked eye (http://people.csail.mit.edu/mrub/vidmag/). This powerful technique can be used to visualize the pulse rate, by just a video stream of the person and can also be used to estimate breathing rate etc. I planned to use this along with ofxBeat/ofxBeatTracking to see if there is any relation between our pulse rate and the beat of music we prefer listening to- so far, haven’t been able to run this plugin successfully.
These plugins can be used to detect the BPM of an audio stream, or the BPM of various frequency bands within the spectrum. Sadly, documentation does not exist anymore (for ofxBeatTracking). I was able to run ofxBeat but the results weren’t as good as expected- nevertheless, tweaking the parameters might do the trick.