Take a screenshot in Raspbian Wheezy

To take a screenshot in LXDE, you will need the application ImageMagick. You can download ImageMagick using apt tool.

sudo apt-get install imagemagick

Once ImageMagic is installed, you can take a screenshot using import command.

import -window root screen.png

You can also combine this command with the delay command to make a delay time before take a screenshot.

sleep 5; import -window root screen.png

This will be delayed for 5 seconds then take a screenshot. Combine sleep command is very handy since you might need to hide the terminal window before take a shot.

Reference: http://stackoverflow.com/questions/10581953/how-do-i-take-a-screenshot-on-a-raspberry-pi-running-debian-squeeze-and-lxde