Spectrogram from AVAudioPCMBuffer using Accelerate framework in Swift

Question

I\'m trying to generate a spectrogram from an AVAudioPCMBuffer in Swift. I install a tap on an AVAudioMixerNode and receive a callback with the aud

Answer 1

4: You have installed a callback handler on an audio bus. This is likely run with real-time thread priority and frequently. You should not do anything that has potential for blocking (it will likely result in priority inversion and glitchy audio):

1. Allocate memory (realp, imagp - [Float](.....) is shorthand for Array[float] - and likely allocated on the heap`. Pre-allocate these

2. Call lengthy operations such as vDSP_create_fftsetup() - which also allocates memory and initialises it. Again, you can allocate this once outside of your function.