I'm a jack newbie, and an audio processing newbie in general. I am trying to develop an audio visualization application. I need to analyze the raw audio waveform data for beat detection from an external source (preferably mic in from the sound card) in realtime. I've been reading through a lot of documentation here but have not really found what I'm looking for. Currently working with jack1 and jack2 built with ALSA on Ubuntu 14.04. Any guidance on where to start with Jack (or some other API) would be greatly appreciated!