I'm developing a Lua application and I need to identify frequencies in an audio recording (Wav format).
By theory, it would be enough to apply a Fast Fourier Transform in the sample sequence and extract the real part.
I got a package of FFT for Lua:
Https://rosettacode.org/wiki/Fast_Fourier_transform#Lua
My first test was with a very simple audio (1 second of 440Hz tone, sample rate 16KHz). The output of the routine would be an array with only the value 440 on all elements ... But it is not working.
I would appreciate any help. I can send the test audio and the Lua routine which reads the wav file and tries to apply the FFT.
Fernando Jefferson