Converting an AudioBufferList to a CMSampleBuffer Produces Unexpected Results

Question

I\'m trying to convert an AudioBufferList that I get from an Audio Unit into a CMSampleBuffer that I can pass into an AVAssetWriter to

Answer 1

It turns out that the fact that the sample size was coming back as 0 was a red herring. Once I cleaned up a few things--notably, I set the timestamp correctly, like so:

uint64_t timeNS = (uint64_t)(hostTime * _hostTimeToNSFactor);
CMTime presentationTime = CMTimeMake(timeNS, 1000000000);
CMSampleTimingInfo timing = { CMTimeMake(1, 48000), presentationTime, kCMTimeInvalid };

recording started working.

So, in the event that someone else is thrown off by the reportedly 0 sample buffer size, be aware that this is OK, at least in the case in which you're feeding the data into an AVAssetWriter.