Avisoft logo

SASLab Manual


Spectrogram window : Tools


Undo last modification This command will undo the most recent modification of the spectrogram (erasing, image filtering).


Playback The marked section is played back through the sound card.

Playback settings…

Heterodyned playback mode…

Stop Stops the playback.


Enlarge Image > The spectrogram image is enlarged by the factor of 2, 4, 8 or 16. Enlarging and subsequent image filtering can by useful to improve the image quality.

Reduce Image > This option allows reversing the above Enlarge Image command.

Zoom out time axis > Zooms out the time axis of the spectrogram display. In large spectrograms this option allows to see a larger section of the file. The internal resolution of the spectrogram (for export commands or Automatic Parameter Measurements) will remain unaffected.

Scroll > left, right, begin, end These commands move the spectrogram window view if the spectrogram is longer than the display window (these commands are only intended for use with the associated keyboard shortcuts).

Scroll > auto scroll…

Image Filter: Average, Image Filter: Median Spectrogram images can be filtered using an average and median filter, which can help removing of noise from the spectrogram. Note that spectrogram structures can be distored as a result of this filtering.


Scan frequency contour and amplitude envelope…

Remove erased spectrogram sections from waveform…

Cursors >

Labels >

Automatic parameter measurements >

Scan for template spectrogram patterns...

Calculate Acoustic Complexity Index (ACI)...


Keyboard Shortcuts and Popup Menu...

Avisoft Bioacoustics last modified on 29 April 2019