Frequency Spectrum of Selected Audio

[dkjMusic 0]

In my Delphi application I select a portion of a wave form for music in a Windows .wav file. I would like to then analyze that selection to produce a frequency spectrum like that in the image below. My objective is to identify the predominant musical pitches in the selection.

 

How can I obtain the amplitude vs. frequency data points for plotting?

[Alexander Sviridenkov 356]

https://en.wikipedia.org/wiki/Fast_Fourier_transform

[Alexander Elagin 143]

Also look here: https://web.archive.org/web/20050307135804/https://www.simdesign.nl/fft.html

The archived version has all the necessary files while the actual site currently produces error 404

[dkjMusic 0]

8 hours ago, Alexander Elagin said:

Also look here: https://web.archive.org/web/20050307135804/https://www.simdesign.nl/fft.html

The archived version has all the necessary files while the actual site currently produces error 404

Alexander, thanks very much for your reply. This looks like just what I am looking for.

 

I'll let you know how it works out.