We have the same problem. It appears to be that ffmpeg was compiled without x264 support (which contains the yuv420p to bgr24 conversion), or for some reason isn't loading it.
This confuses me, as others are able to use the camera with the SmartDashboard.
Replacing ffmpeg usually requires a recompile of dependent programs (usually not binary compatible), which in this case means OpenCV. I'd feel comfortable doing this on a real operating system, but am unsure of what I need to do on Windows.
I have verified that
http://10.10.24.11/mjpg/video.mjpg is a valid video stream, and that it is ffmpeg/OpenCV that is having problems reading it.
We are using the 2012 image for the E09 netbook.