Does repeatedly saving a video degrade its quality?

Question

I take a video file, let's say an mp4, and use, let's say Windows Movie Maker, to repeatedly just save it, with no edits. Every time, the software has to convert the video into a format it can edit, and then convert it back to an mp4. Will the repeated conversions begin to degrade the video's quality if I do this over and over?

Answer 1

In theory there will be a big change the 1st time you do compression. All further changes should be minimal. BUT! If you pick to low a quality then file integrity can be diminished.