What you cannot do, however, is convert old videos in iMovie, Final Cut Pro or QuickTime Player on Catalina-powered systems. 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. 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. MacWorld’s Glenn Fleischman has more details: Contact developers of third-party apps for more information about media formats supported in their apps. Third-party developers may continue to offer compatibility with some formats by building support directly into their apps. It may also mean more work for developers to ensure compatibility, Apple indicates: That’s because macOS Catalina dropped support for 32-bit apps and Apple’s never bothered to update software components for decoding older video formats to 64-bit compatibility.Īpple’s support document lists more than three dozen older media formats affected by the transition to 64-bit technology in macOS Catalina, like RealVideo, DivX, Sorenson 3 and FlashPix, in addition to other formats that were superseded by improved encoders:Įxamples of media that will be affected by the transition to 64-bit technology include video files from early Flip Video cameras that use the 3ivx codec, early web videos encoded with the Sorenson codec and media converted from DVD to the DivX format.Īs a result, apps like iMovie and QuickTime Player cannot play those old formats in Catalina.

Did you know that many of the old videos you keep stored and encoded in outdated formats may refuse to play under macOS 10.15 Catalina without some third party help?

Imovie for catalina