Spectrogram
Definition
A time-frequency plot in which the horizontal axis is time, the vertical axis is frequency, and colour or brightness encodes signal energy. The primary visual tool for audio authentication. Discontinuities appear as abrupt vertical changes in spectral energy distribution.
Related terms
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- Statistical characterisation of the ambient noise floor in quiet segments of a recording, including its average level, spectral shape, and stationarity. Changes...
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- Any point in an audio recording where a physical property of the signal changes abruptly in a way inconsistent with natural acoustic...
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- Phase Discontinuity
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Explained in these topics
- Detecting Discontinuities in Audio RecordingsA time-frequency plot in which the horizontal axis is time, the vertical axis is frequency, and colour or brightness encodes signal energy. The primary visual...
- Forensic Acoustics and Gunshot Acoustic AnalysisA two-dimensional representation of the frequency content of an audio signal over time, produced by Short-Time Fourier Transform; the primary display format fo...