fourier transform

Years ago, I posted here an app I wrote, called soundspec, that could take an audio file, or many files, and creates a spectrogram PNG image from each file. That app is old, and was never very portable. I re-wrote that app recently in Go. It now runs on many operating systems (macOS, Windows...

If we look at what comes out of our electronics it is in time domain. One value after another. Fourier transform allows us to see the frequency components of a time domain signal. It is a non-intuitive thing to get one's mind around. However difficult though, this is a fundamental concept in...