Update June 25, 2015: iMovie 10.0.9 has been released which fixes the problem I describe below.
Recently, I’ve been enjoying using my GoPro camera with iMovie to put together silly little videos. I recently upgraded my MacBook to OS X 10.10 Yosemite, and at the same time accepted the automatic upgrade of iMovie to version 10.0.0.6. After doing so, I realized that all my previously-imported GoPro videos wouldn’t play in iMovie anymore, showing as “empty” tracks instead. I also couldn’t import converted video into iMovie anymore.
To back up a bit, I’ll explain how I usually work with GoPro videos. I shoot video with my GoPro using the “ProTune” mode, and then import those videos onto my Mac. From there, I convert them into an editing-friendly CFHD (CineForm HD) format using GoPro Studio. GoPro Studio understands ProTune, and offers nice color correction and exposure controls - much better than iMovie can offer. After color correcting the clips, I’ll import them into iMovie and then deduplicate them using a script so that I can still use GoPro Studio to make further color tweaks while editing in iMovie. I can then use iMovie, which I quite like, to edit my videos, add music, etc.
Unfortunately, that workflow is now broken because iMovie no longer recognizes the CFHD video format. It can import the original, pre-converted videos from the GoPro, but thanks to the ProTune recording mode, those videos require extensive color manipulation to look good (which GoPro studio does as part of its conversion process). To work around this limitation, I’ll either have to switch to doing all my video editing in GoPro Studio (which is pretty limited) or export my videos to an h.264 encoding from GoPro Studio so iMovie can use them. I’m not really excited about the latter option as that means yet a third copy of my video, and I won’t be able to tweak videos in GoPro Studio after I’ve exported them.
I’m not sure exactly what’s going on, but if I were to hazard a guess it’s that OS X Yosemite and iMovie 10.0.0.6 are continuing with Apple’s migration away from Quicktime (which allowed for third-party video codec plugins, like CineForm’s CFHD plugin) to AV Foundation, the media framework from iOS that Apple has brought back across to OS X. Unlike Quicktime, AV Foundation only supports a limited set of video formats, and does not allow for external plugins that add support for other formats. This is why, for example, Perian no longer works. I had hoped that iMovie, being cut from the same codebase as Final Cut Pro, would be exempt from this dumbing-down. I wonder why this happened, without announcement, and in a point release of the software. I’m also not sure, if this is really the case, what GoPro/Cineform could do about it now that Apple has closed off any avenue for third parties to extend OS X’s media capabilities. It certainly doesn’t make me want to jump up to Final Cut Pro and wonder whether things would be better supported there.
That said, I haven’t done a lot of extra research to validate my theory. I haven’t confirmed that other formats no longer work with iMovie, and I haven’t tried a Mac with Yosemite but without the new iMovie to help narrow down which one may have introducted the change.
I’ve searched around for reports of other people having this problem, and I’ve found a few Apple support forum posts (no answer) but not much else. I opened a support ticket with GoPro, but they were clueless and eventually stopped responding to me. My hope is that by documenting this problem, this post will at least be somewhere for others in my situation to commiserate, or even better, to tell me I’m wrong and I just need to do X to fix everything.