Define a call

Aim

To create a call definition, which can be used to detect vocalizations automatically, based on frequency, amplitude and time parameters.

Prerequisites

nChoose Analysis > Call detection, or in the Experiment explorer choose Call Detection. Next, choose a recording from the list.

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nMake sure that Spectrogram is selected in the View box.

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To define a call

1.Filter the signal. If you want to analyze frequencies above a threshold, under View click the Filter button.

In the Filter window, enter this threshold in the Cut off frequency field, then click Apply.

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2.Click the step forward button until you find a suitable call spectrogram.

optional  Adjust the Time interval to be visualized in the Spectrogram.

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3.Drag the mouse around the call spectrogram. Make sure that all the frequencies you want to use to define the call are included.

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The call is highlighted and labeled with a Call name indicating the frequency range.

4.If you drag the mouse around the call, the Edit Call Definition window appears. Adjust the parameters if needed, then click OK.

5.Adjust the parameters to improve call detection. See How to detect more calls

6.Let UltraVox XT Search for calls.

Notes

nThere are other two ways to define a call: Add a call with specific parameters and Load a call template.

nFor a better view of the calls, Zoom in/out the spectrogram.

nThe Spectrum shows the frequency range selected when you select a region of the spectrogram.

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nIn the Call Definition list, a new row appears with the current frequency, amplitude and time parameters of the call definition.

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In the Spectrogram, the call is highlighted with a rectangle of the same color as that in the Call Definition list.

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The width of the rectangle is the Minimum duration in the Call definition.

The height of the rectangle is the frequency range. You can adjust this range. See Adjust a call definition

nThe call definition is given a default name based on the frequency range (for example, 52-65k).

nAt the right side of the Detected Calls list, you find an enlarged spectrogram of the call.

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