STFT demo (low sample rate, naive DFT)

Designed for a 960×700 iframe

Signal Sample rate (Hz) Duration (s) Window N (samples) Hop H (samples) Window

Frame index (moves analysis frame)

Signal samples (highlighted region = current frame)

Windowed frame (samples) + window curve

Magnitude spectrum (DFT bins of selected frame)

Spectrogram (magnitude, dB-ish; time=frames, freq=bins)

Δf = Fs/N (bin spacing). Hann reduces leakage vs rectangular.