ofxMetronom is an addon for openframeworks https://github.com/openframeworks/openframeworks. This little util sends periodically bangs, which can be used to trigger video or audio for instance.
git clone https://github.com/thomasgeissl/ofxMetronom.git /path/to/your/openframeworks/addons/ofxMetronom
replaced ofxMSATimer with ofTimer
replaced custom event with tick event added setters for min time and max time