Signal detection software
Omura’s whale detector
Omura’s whales (Balaenoptera omurai) occur in tropical waters off western and northern Australia. They produce song by repeating an amplitude-modulated low-frequency (15-62 Hz; 12-15s) vocalisation every 160-210s. The detector looks for this sound. It computes a spectrogram and then the Shannon entropy of the spectrogram looking for non-random pixels. The detector consists of three files: OmuraEntropy2XSTD_JASA.m, which calls imageEntropy.m and spectha2M.m. You need MATLAB (The MathWorks Inc., Natick, MA, USA) to run the detector.
Madhusudhana, S., Murray, A., and Erbe, C. (2020). Automatic detectors for low-frequency vocalizations of Omura’s whales, Balaenoptera omurai: A performance comparison. The Journal of the Acoustical Society of America, 147(5), 3078-3090, doi: 10.1121/10.0001108.
Automatic detectors for pygmy blue whale song, fin whale 20-Hz downsweeps, and the ‘spot’ call are incorporated in the CHORUS software package, for download here.