where can I find video4linux2 device /dev/video in ubuntu 9.04

where can I find video4linux2 device /dev/video in ubuntu 9.04.

ADDED.

I want to work with Hardware Overlay开发者_Python百科s. I want to make a video player which play video on one overlay and draw controls on other overlay. For that I want to use video4linux.

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First you need to load a driver (webcam driver for example) which will create /dev/video interface.