Apple sheds the past as necessary to provide new features in its products. With macOS 10.15 Catalina, Apple gave up on 32-bit software after two years of Apple warning about that event coming. That meant iPhoto and a host of third-party apps could no longer be used after upgrading. But less remarked upon were video formats that relied on software components Apple had never updated to 64-bit compatibility.
There’s a long list of formats dropped in last fall’s macOS update, and it includes faves from years past: RealVideo, DivX, Sorenson 3, FlashPix, and many great hits that eventually were superseded by improved encoders. (An encoder takes a stream of video and represents it with a certain degree of fidelity to the original, while storing it efficiently, and often in a way that is also designed optimized for rapid, smooth playback as the data is read out of the file.)
iMovie and Final Cut Pro were both updated in March 2019 so that when running under macOS 10.14 Mojave and some previous compatible releases, the apps alerted you when any project you opened contained clips that would be incompatible in Catalina, and converted them to a newer format. You could also open any file in QuickTime Player in Mojave or earlier releases and save a copy, which would automatically save it in a newer format that will work in Catalina (and far beyond).
In Catalina, however, iMovie, Final Cut Pro, and QuickTime Play can’t convert the old formats.
If you’ve already upgraded to Catalina, you can lean on two free, open-source video players that keep up to date with formats and macOS: IINA and VLC. They can play nearly every old format, and VLC can convert and save files.
This Mac 911 article is in response to a question submitted by Macworld reader Jewel.
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