[jmartin]

Using the signal mode of raspistill is something I hadn't thought of. That must be pretty slow though, since you have to wait for the image to be written out and then read it back in. I'm hoping to track the balls so I need a pretty high framerate (and as I mentioned, it looks like I'll have it), but for identifying when the goal is hot in autonomous mode, fetching images with raspistill is probably fast enough and easier to accomplish.