> Can’t open dashcam footage
Since upgrading my MacBook Pro to Big Sur it won’t play footage from my Thinkware F770 dashcam, and reports it “cannot open files in the MPEG–4 movie format”. Why is this?
One of the smaller casualties with the loss of 32–bit software support in Catalina and Big Sur is that QuickTime codecs used to record and play back certain video and audio formats no longer work. Although most Mac apps have been updated, some older or cross–platform software hasn’t caught up.
You’ll notice this if you’ve recently upgraded macOS from Mojave or earlier to Catalina or Big Sur. Apple has a list of formats which lost support when those old QuickTime codecs were lost, at bit.ly/ ml183QTmedia. Among them are Flash Video, RealVideo, WMV, and Perian codecs.
MacOS provides support for the conversion of those retired formats in Mojave, but not in subsequent 64–bit versions of macOS such as Big Sur. If you want to convert or access movies in those formats, then Mojave is your best prospect.
In your particular case with not being able to open footage, dashcam footage is being saved using a codec which is no longer supported. If the manufacturer is unable to provide an update to the dashcam, or software it provides giving access to footage, you’ll need to replace the dashcam with a model which uses a supported format.