I use Time Machine – the automatic backup feature of Mac OS X 10.5 Leopard – as one part of my overall backup strategy, and although most of the time I never think of it, Time Machine occasionally saves my bacon. Tonight, it salvaged a corrupted iMovie project file.
Working on the new chapter of my iMovie Visual QuickStart Guide that covers themes and maps, I had just specified a custom still image for a theme transition and then undid the edit to take a screenshot.
Something in that action caused iMovie ’09 to freak out, because afterward some clips in my project would appear as black when skimmed or played back, and others contained still versions of completely different clips. Quitting and restarting iMovie and rebooting the computer didn’t help (I at first suspected a low memory issue, since I’m running Adobe InDesign CS4, Adobe Photoshop CS4, iMovie, and a half dozen other applications on my MacBook Pro with 3 GB of RAM).
Figuring that the event thumbnails had become corrupted, I quit iMovie and searched through my Event folders in the Finder and deleted all folders called iMovie Cache and iMovie Thumbnails. Doing so forced iMovie to rebuild those items when I launched the program again (which can take a long time if you have a lot of source video). Unfortunately, that didn’t solve the problem.
Suspecting a corrupted project file, I selected the file in question in the Finder (in my iMovie Projects folder) and clicked the Time Machine icon in the dock to enter Time Machine. I jumped back several hours to the early afternoon, clicked the Restore button, and in a second I had a fresh, uncorrupted version of my project.
I lost a few hours of editing work, but that’s nothing compared to the possibility of ditching the entire project and starting over from scratch.
[Related plug: I highly recommend Joe Kissell’s Take Control of Mac OS X Backups, an ebook I edited, for the information you need to create and maintain an effective backup system. I’d recommend it even if I wasn’t involved in its production.]