Introduction

Spectral Flow Detection

Spectral flow detection is done with two type of markers that detect quick energy variations increase or decrease in the signal.

Spectral Flow Markers

Positive and Negative Differencing

  • Positive spectral differencing detects a quick increase of energy, as in the case of an attack for instance.

  • Negative spectral differencing detects a quick decrease of energy, as in the case of the end of a note.

Starting the Analysis

To trigger the analysis, press Alt + Cmd + M or choose Analysis/Generate Markers.

In the upper pop up menu of the dialogue window, choose Spectral Differencing (positive-negative)

Markers will be displayed across the waveform and sonogram windows.

Saving Markers
Analysis Parameters

As shown by the dialogue window, the accuracy of the analysis entirely depends on the FFT parameters.

FFT Parameters

Representation, Manipulation and Edition

Representation

  • Markers are represented at the bottom of the sonogram by a small triangle, with a line crossing the whole waveform and sonogram windows.

  • Positive spectral flow markers are pink.

  • Negative spectral flow markers are yellow

  • A selected marker is bright red.

Manipulation, Display and Edition

Spectral flow markers can be manipulated like manual markers. The number of displayed markers can be controled after the analysis. They can also be partially edited.

Manipulation, Display and Edition
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