Simple video rotate

[troogyt]

How do I simply rotate a video then save it as rotated?

I have a bunch of videos taken on a smart phone but the smart phone has incorrectly saved them with a 'sideways' orientation (for example as portrait when they should be landscape), so I need to rotate them all then save them with the correct orientation.

I can rotate the video with "R", but it does not save the video as rotated. When I play it again it hasn't changed.

[troogyt]

I found this: YouTube