Follow these steps to convert your videos to 1080p using QuickTime Player included with Mac OSX / MacOS
This will output a maximum of 1080p at10 Mbit/s H.264 for playback in ~sedna.
Note: This will not change the frame-rate of the video file. Ideally the frame-rate of your video file should match the frame-rate of your display.
1. Right click on video and select Open With -> QuickTime Player
2. In the QuickTime menu select File -> Export -> 1080p...
3. You can rename and select where you want to save the video file. Select Save to export the video file to 1080p.