←back to thread

What Is the Fourier Transform?

(www.quantamagazine.org)
474 points rbanffy | 1 comments | 04 Sep 25 22:11 UTC | HN request time: 0.246s | source
Show context
eric-burel ◴[05 Sep 25 11:45 UTC] No.45137452[source]▶
What always bothered me when trying to "feel" Fourier transforms is that to compute the oscillations, you need to wait some time. Mathematically, the transformation includes computing integrals. So it's tricky to understand how you compute the Fourier decomposition for a stream. Illustrations always show the whole signal over time but in real life you get the signal progressively. I'd be eager to read more on this.
replies(5): >>45137577 #>>45137594 #>>45137601 #>>45137735 #>>45137768 #
1. acjohnson55 ◴[05 Sep 25 12:32 UTC] No.45137768[source]▶
Check out https://en.m.wikipedia.org/wiki/Short-time_Fourier_transform

This is the "Fourier transform" that is most often used, in practice in computing.

A longer window length gives lower frequency resolution, but longer latency.