
thumb|upright=1.35|Spectrogram of the spoken words "nineteenth century". Frequencies are shown increasing up the vertical axis, and time on the horizontal axis. The legend to the right shows that the color intensity increases with the density. thumb|upright=1.35|A 3D spectrogram: The RF spectrum of a battery charger is shown over time
thumb|upright=1.35|Spectrogram of the spoken words "nineteenth century". Frequencies are shown increasing up the vertical axis, and time on the horizontal axis. The legend to the right shows that the color intensity increases with the density. thumb|upright=1.35|A 3D spectrogram: The RF spectrum of a battery charger is shown over time
A spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. When applied to an audio signal, spectrograms are sometimes called sonographs, voiceprints, or voicegrams. When the data are represented in a 3D plot they may be called waterfall displays.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).