Blackmagic Forum

Do Resolve V12.5 or V14.x remove implicit and explicit priming samples from the head and tail of AAC stream as described here:

https://developer.apple.com/library/con ... ppenG.html

I have an MP4 file with AAC audio generated in Clipster. When this MP4 is loaded back to Clipster the sound is in perfect sync with the original media used to encode the MP4.

However, when I drop this MP4 file onto Resolve V12.5 timeline the audio waveform is delayed by about a frame at 23.976 fps.

This 41.7 ms of delay seems pretty close to the implicit priming sample delay of 2112 samples or 40 ms at 48 KHz. This would suggest Resolve does not remove the empty samples and the clip plays back out of sync.

Sorry you didn't get a reply to this last year! Anyway, was looking for an old comment thread I started back in 2017 about this exact issue. It seems that Resolve (at least when you tested this - has it changed?) has the same issue that all QT Kit / QT7 based systems have. Please see here:

https://forums.developer.apple.com/thread/81268

Does seem like this is fixed now, so guessing Resolve no longer uses any of the QT Kit stuff!

Thanks Mark, I can't remember any longer what this was all about. It was probably some fire I was putting out at the time.