AVFoundation in Yosemite
There is a lot of new audio functions. A lot, as in heaps.
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We’ve had AVAssets and AVCompositions in AVFoundation up until now, which do not support reference movies. It seems a reasonable inference that an AVFragmentedMovie is what we’d have called a QT Reference movie in the past.
Update (2014-10-18): Mike Ash:
I was excited to try AVAudioEngine now that 10.10 is here. But it’s just sadness and silent failures and mysterious crashes. Sigh.