This library is full of additional and useful links and comments about how an FFT result can be used to get a frequency spectrum. In this document I want to give a short introduction where inside the code you can find specific things.
TL;DR: Although this crate has over 1000 lines of code, the part which gets the frequency and their values from the FFT is small and simple. Most of the code is related to my convenient abstraction over the FFT result including several getters, transform/scaling functions, and tests.
I don't explain how FFT works but how you use the result! If you want to understand that too:
- check out all links provided at the end of README.md
- look into
lib.rs(probalby gives you 90 percent of the things you want to know) and the comments over the FFT abstraction insrc/fft/mod.rsandsrc/fft/rustfft-complex/mod.rs.
This is everything important you need. Everything inside
spectrum.rs and the other files is just convenient stuff + tests for when you
want to use this crate in your program.