I had a video of a group that I wanted to learn the moves of, but the video was taken from the front, and my brain doesn’t cope with mirroring in my head that quick, so I thought I would mirror the video file.
Thankfully I already had everything I needed – the video file and ffmpeg.
Kind of simple when you know how:
>ffmpeg -i orig.avi -vf "hflip" flipped.avi
Then I just needed to put the flipped file back into my Movies folder for Plex to pick up, et voila I was moving with the best of them!