Fourier Transform Visualizer
Draw a signal · see its DFT · filter interactively
Preset:
Draw custom
Single sine
Square wave
Sawtooth
Chirp
Impulse
Gaussian
Freq:
3
Clear
Low-pass
High-pass
Band-pass
No filter
Cutoff:
8
Top: original signal (draw with mouse). Middle: DFT magnitude spectrum. Bottom: filtered signal. Uncertainty principle: Δt·Δf ≥ 1/(4π) — narrow in time ↔ broad in frequency.