I am working on Fourier Transformation, and applying this for recognizing an audioclip.
I have a 9 second long audio clip of a guitar strumming an A-Minor. The audioclip has a sampling rate of 44100 Amplitudes per second, and a bitdepth of 16 bits.
I do a fourier Transform of the audiofile(green graph), and get a spectrum where the samples are the x-axis. I want to have frequencies along the x-axis, for being able to recognize the pitches, so I again can recognize the chord that is being played.
Instead I get samples. How can I convert this to frequency?