I made a recording of some hummingbirds at the feeder today. I was thinking that since I want to learn how to do microphone input into a microcontroller, an interesting project would be to build a hummingbird detector, which could then trigger a camera or something.

  • Elle Plato - Their wingbeat frequency should be unique, since most animals cruise at their struval number. Mic -> DSP -> camera activation -> profit. Oh wait, wrong business model.
  • John Ridley - I'll be using a generic microcontroller, not a dedicated DSP, because the purpose of the exercise is to learn to interface microphones with microcontrollers. It is my hope that wingbeat frequency is detectable, though of course it's slightly different between males and females and juveniles, and of course in other parts of the country, there will be other species.
  • Elle Plato - If you'd like I have some FFT and Goertzal transforms coded in PERL lying around somewhere. I think a Goertzal would be a lot more efficient for what you want. I need to learn to do wavelet transforms, but have not had the time.
  • John Ridley - It'll probably be months before I get around to this, too much else to do now. When I do I'll check to see if there are already libraries available for the AVR chips first, no point in re-inventing the wheel (or having to port code that's already been ported). Thanks.