VLC has a snapshot item on the Tools menu, which will take a snapshot of the video and save it as a bmp file.
How can I take screenshots?
To take a snapshot of the video
displayed by VLC, you just need to
press the pre-defined snapshot hotkey:
* Windows / Linux / Unix: Ctrl+Alt+S
* Mac OS X: Command+Alt+s
To change it, go to Preferences ->
Interface -> Hotkeys settings, check
Advanced options, and set Take video
You can also take a snaphot via the
menu Video -> Snapshot.
To change the snapshot format or
directory, go to Preferences -> Video.