I'm trying to understand the difference in frame rate when I use the same camera on two different machines running Windows XP, the latest version of DirectX, and the latest drivers for the webcam. The two systems are:
1. HP Pavillion tower with 2.2 GHz AMD and 3 Gb RAM
2. Mini-ITX single board computer (EN12000EG) running at 1.2 GHz with 1 Gb RAM
The camera is a Creative Labs Voice! that I specifically chose because it has one of the widest FOVs among available webcams (about 75 degrees).
Running the same version of RoboRealm (the latest), no modules, preview off, resolution set to 160x120, and the webcam set to the lowest exposure setting (1), I get nearly 30 fps on the HP and only 13 fps on the Mini-ITX. CPU load on the Mini-ITX is only 50% so it doesn't seem to be a load issue.
I have one clue that might be critical: using the Creative supplied "Cam Center" software, I can view the video image on either machine outside of RoboRealm. When I do this, the video is noticeably slower on the Mini-ITX which is consistent with the RoboRealm results. But even stranger--the Cam Center software has an option to superimpose the frame rate on the image--on the HP this option is functional and displays 27 fps on the image, again consistent with RR. However, on the Mini-ITX, this option is greyed out! So it's as if there is some subtle interaction between the Creative webcam driver, DirectX, Windows XP and the Mini-ITX. I don't expect you to spend any time debugging this since it doesn't seem to be a RoboRealm problem, but if something obvious jumps to mind, I'd love to hear it.