I need to write a program that does some LK optical flow calculations on an USB webcam feed using OpenCV. This has to be on an embedded system.
I currently own a Raspberry PI revision A coupled with Microsoft LifeCam VX-500. Althrough the camera works correctly in 640x480 resolution, I am getting at most 3 FPS with a simple program that just captures the frames and does nothing with them (not even display them). When I apply LK optical flow calculations, one frame takes around 640ms to process. This is unacceptable.
I do not exactly know why this is so slow, on one hand a bunch of USB issues are reported with PI that would slow down frame grabbing from the camera, on the other hand many say the PI's CPU is simply too slow in floating point operations that it is practically unusable to do image processing.
What is the culprit of this slowness? PI is fully updated, using raspberian, newest opencv (downloaded week ago), compiled fine, just very slow.
If PI is not a way to go, I am looking for a replacement system, any suggestions are welcome. Perhaps one of these? http://www.efytimes.com/e1/creativenews.asp?edid=84368 Or this one http://www.marsboard.com/? Or perhaps an intel Atom board? Which would be the best?
I need to achieve at least 15 frames per second with calculations taking place, 25 frames per second would be optimal.
Thanks a lot.