The default video player used by video looper is omxplayer. This is a great general purpose video player that offloads video decoding to the Pi's GPU so it can render 720p and even 1080p video on the Raspberry Pi 1 and Pi 2.
To use omxplayer you'll want to make sure your video is encoded with an H.264 codec and is in a file format like .avi, .mov, .mkv, .mp4, or .m4v. If you have a video in a different format or that won't play you convert it into an H.264 video easily with some free tools.
For converting a video to H.264 that omxplayer can play I recommend the Handbrake video transcoder tool. This tool is available for free for Windows, Mac, and Linux machines, and has a relatively simple interface.
To use Handbrake, after installing it open the program and you'll see a display like this:
Click Source in the upper left and load your video to see information like the dimensions, framerate, encoding, etc. By default Handbrake's normal encoding preset works well, but I recommend tweaking a few of the settings to improve the quality and reduce issues with looping short videos.
Once a video is loaded click the Video tab and adjust the settings to:
- RF = 18
- Profile = high
- Level = 5.0
Below is an example:
Then enter a new destination file name and press the Start button at the top to transcode the video into a .m4v file.
Be aware video transcoding can take some time if your computer has a slow CPU or the video has a long length.
Once Handbrake is done transcoding the file copy it to a USB drive and try playing it with the video looper.
Note that the version of omxplayer installed by video looper is actually a fork of the original code and was made to help reduce the latency when looping a single video. You don't need to worry about how to install or use this updated omxplayer as the video looper install script takes care of everything automatically.
In the future it's possible the main omxplayer project will integrate these changes. Be aware if you manually install video looper or wish to modify and extend it that you'll want to use the forked omxplayer code above.