Linux script that captures mouse movement, and snaps a webcam shot: libraries?

I'd like to write a script that once run on Ubuntu, captures any mouse movement and immediately uses the installed webcam to save a sn开发者_开发知识库apshot to the desktop. I'd like to know which libraries are standard for this sort of programming.

Thanks!

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Found the answer. opencv for python (highgui) takes care of the webcam, and Xlib takes care of the events.

Use python DBUS to send a Lock signal to a screensaver.