title: Automated extraction of odontocete whistle contours.
abstract: Many odontocetes produce frequency modulated tonal calls known as whistles. The ability to automatically determine time × frequency tracks corresponding to these vocalizations has numerous applications including species description, identification, and density estimation. This work develops and compares two algorithms on a common corpus of nearly one hour of data collected in the Southern California Bight and at Palmyra Atoll. The corpus contains over 3000 whistles from bottlenose dolphins, long- and short-beaked common dolphins, spinner dolphins, and melon-headed whales that have been annotated by a human, and released to the Moby Sound archive. Both algorithms use a common signal processing front end to determine time × frequency peaks from a spectrogram. In the first method, a particle filter performs Bayesian filtering, estimating the contour from the noisy spectral peaks. The second method uses an adaptive polynomial prediction to connect peaks into a graph, merging graphs when they cross. Whistle contours are extracted from graphs using information from both sides of crossings. The particle filter was able to retrieve 71.5% (recall) of the human annotated tonals with 60.8% of the detections being valid (precision). The graph algorithm's recall rate was 80.0% with a precision of 76.9%.
authors.affiliation: San Diego State University, Department of Computer Science, 5500 Campanile Drive, San Diego, California 92182-7720, USA. marie.roch@sdsu.edu
authors.forename: Marie A
authors.initials: MA
authors.lastname: Roch
authors.forename: T Scott
authors.initials: TS
authors.lastname: Brandes
authors.forename: Bhavesh
authors.initials: B
authors.lastname: Patel
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Barkley
authors.forename: Simone
authors.initials: S
authors.lastname: Baumann-Pickering
authors.forename: Melissa S
authors.initials: MS
authors.lastname: Soldevilla
mesh_terms: D000465:Algorithms; D000818:Animals; D001499:Bayes Theorem; D004289:Dolphins / Q000502:physiology*; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted; D013018:Sound Spectrography; D013997:Time Factors; D014828:Vocalization, Animal