Can't open DV video (dvsd) AVI file with QuickTime I am using macOS Catalina. I want to open an AVI file with QuickTime. However, I get an error message saying that the file is not compatible with QuickTime.

I am able to open the file with VLC. It says that the video codec is "DV video (dvsd)". Is there a codec I can install to open the file with QuickTime?
QuickTime doesn't accept 'plug-in codecs' any more, not since QuickTime 7.

There used to be a plug-in set by the name of Perian, which was the Swiss army knife for QuickTime, but it no longer works.

Your best bet would be to transcode from VLC or any of the other encoding apps available, if you specifically need it in QuickTime.

I always think of .AVI as being very much a 'Windows' structure [even if that's not strictly true], so I've avoided it on Mac for many years, or immediately transcode to something more portable.