espectrograms

An spectrogram is a visual representation of the spectrum of frequencies of a signal as it varies with time. It is a powerful tool used in various fields, including audio processing, speech recognition, seismic analysis, and radar. Essentially, an spectrogram displays the intensity or amplitude of different frequencies present in a signal over a specified duration.

The horizontal axis of an spectrogram typically represents time, while the vertical axis represents frequency. The color or intensity of a point on the spectrogram indicates the amplitude of that particular frequency at that specific time. This allows users to observe how the frequency content of a signal changes and evolves. For instance, in an audio spectrogram, different notes or sounds would appear as distinct patterns of color at different frequencies and times.

The generation of an spectrogram involves a process called the Short-Time Fourier Transform (STFT). The STFT analyzes segments of the signal over short, overlapping time windows. For each window, a Fourier Transform is performed to determine the frequency components present. By stacking these results side-by-side, a full time-frequency representation is created. Spectrograms are invaluable for identifying patterns, anomalies, and characteristics within complex signals that might not be apparent from other analysis methods.