Create a silent audio CMSampleBufferRef

Question

How do you create a silent audio CMSampleBufferRef in Swift? I am looking to append silent CMSampleBufferRefs to an instance of AVAssetWriter

Answer 1

You need to create a block buffer using CMBlockBufferCreateWithMemoryBlock(). Fill the block buffer with a bunch of zeros and then pass it into CMAudioSampleBufferCreateWithPacketDescriptions().

Disclaimer: I haven't actually done this in Swift, I attempted it but found myself fighting the compiler at every turn so I switched to obj-c. The Core Media Framework is a low level C framework and was a lot easier to use without screwing around with Swifts type system. I know this isn't the answer you're looking for buy hopefully it will point you in the right direction.

Example