You can recover deleted videos from iPhone at ease. Follow:
===>First of all connect your device to PC over USB.
===>Now Launch iTunes in your PC.
===>Select your Device there by clicking on your device.
===>After connecting click on Backup & Storage option there.
===>Now click on Backup option there.
===>Then click on Restore Backup.
===>This action will restore deleted data back to your device.
I think this has already been mentioned...