OpenCV Python and a webcam

I'm working with OpenCV on a BeagleBoard with Ubuntu and OpenCV 1.1 interfaced via Python. I'm trying to set something up to capture a feed from a UVC compatible w开发者_开发百科ebcam (Logitech C250). I have tested the webcam with luvcview, and it works, but only if I set the input format to YUV. If I run it in 'normal' mode I am getting back JPEG frames and something - somewhere is not happy!

I'm trying to connect with the webcam in OpenCV as I want to get the image back from the webcam and run some analysis on it. As I have a limited device this seems to be the most efficient way of doing it - however I need to instruct the capturing system to capture in YUV and not JPEG. Is there a way of doing this (for example luvcview allow me to enter luvcview -f YUVY)?

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I've cracked this partly. If you compile OpenCV with the flag WITH_JPEG=OFF then the camera will not try to use MJPEG.