# Spectra: Every signal is a sum of sines

> A radix-2 Cooley-Tukey FFT (and inverse) with a Hann window, driving paired time- and frequency-domain views. 14 tests using the transform's own identities - Parseval energy conservation, exact inverse round-trip.

Spectra is an interactive Fourier-transform explorer that decomposes a signal into its constituent frequencies and shows the time- and frequency-domain views side by side. The signature technique is a from-scratch radix-2 Cooley-Tukey FFT with a Hann window, verified against its own mathematical identities such as Parseval energy conservation and an exact inverse round-trip. It is a dependency-light build you can download and run locally.

## About the app

Signal processing

## What to take away

- A radix-2 Cooley-Tukey FFT (and inverse) with a Hann window, driving paired time- and frequency-domain views. 14 tests using the transform's own identities - Parseval energy conservation, exact inverse round-trip.
- Download: Spectra (ZIP)

## Tags

Free software, Spectra

## Read the full write-up

/downloads/spectra.zip

## We build this for clients

https://dfieldsolutions.com/en/services/full-stack

## More from the lab

- https://dfieldsolutions.com/en/lab/sylex.md — Sylex: Make sense of the slashes
- https://dfieldsolutions.com/en/lab/kindra.md — Kindra: Miss a beat, not the rhythm
- https://dfieldsolutions.com/en/lab/voxara.md — Voxara: Argue better. Lose gracefully
- https://dfieldsolutions.com/en/lab/wraithward.md — Wraithward: Spot the bait before you bite

---

Source: https://dfieldsolutions.com/en/lab/spectra
DField Solutions — Torony köz 5-1.a, 2120 Dunakeszi, Hungary — +36 20 722 0002 — dezso@dfieldsolutions.com
Booking: see https://dfieldsolutions.com/en/contact