Howtosignalprocessing
How do spectrograms work?
A spectrogram is a visual way of representing the signal strength, or “loudness”, of a signal over time at various frequencies present in a particular waveform. Not only can one see whether there is more or less energy at, for example, 2 Hz vs 10 Hz, but one can also see how energy levels vary over time.
How do I read a spectrogram?
In the spectrogram view, the vertical axis displays frequency in Hertz, the horizontal axis represents time (just like the waveform display), and amplitude is represented by brightness. The black background is silence, while the bright orange curve is the sine wave moving up in pitch.
How do audio spectrograms work?
Spectrograms map out sound in a similar way to a musical score, only mapping frequency rather than musical notes. Seeing frequency energy distributed over time in this way allows us to clearly distinguish each of the sound elements in a recording, and their harmonic structure.
