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Physics

Time-Frequency Analysis

Quick fact

A standard Fourier transform shows all the frequencies present in a signal, but it loses all information about when those frequencies occur. Time-frequency analysis fixes this by letting you watch the spectrum evolve moment by moment.

Why this is interesting

You can easily see when a sound is loud or quiet on a waveform, but how do you see which note is being played at each moment—like reading a musical score from a recording?