Configuring
FFT Engine
Configuring an FFT Engine
The FFT Parameters dialog is shown automatically when a new FFT Engine is created. It can also be accessed in the two following ways
1. From the Detection>FFT Parameters� menu 2. From the pop-up menu on the FFT Engine window in the PAMGuard Data Model display.
Select a data source
From the drop down list select a source of audio data. When you select a new data source, the channel list will be updated to show the number of channels in the selected data source. Tick the check boxes for the channels you wish FFT data to be computed for.
To save processor power, do not calculate FFT data for channels that are not needed in subsequent PAMGuard processes.
Set the FFT Length
This must be an exact power of 2.
Set the FFT Hop
This is the number of samples between the start of successive FFT blocks - often this is set to half the FFT length to provide overlap.
Set the Window type
Select a windowing function from the following options:
Rectangular
Hamming
Hanning
Bartlett (Triangular)
Blackman
Blackman-Harris