ISCA Archive Interspeech 2020
ISCA Archive Interspeech 2020

ORCA-CLEAN: A Deep Denoising Toolkit for Killer Whale Communication

Christian Bergler, Manuel Schmitt, Andreas Maier, Simeon Smeele, Volker Barth, Elmar Nöth

In bioacoustics, passive acoustic monitoring of animals living in the wild, both on land and underwater, leads to large data archives characterized by a strong imbalance between recorded animal sounds and ambient noises. Bioacoustic datasets suffer extremely from such large noise-variety, caused by a multitude of external influences and changing environmental conditions over years. This leads to significant deficiencies/problems concerning the analysis and interpretation of animal vocalizations by biologists and machine-learning algorithms. To counteract such huge noise diversity, it is essential to develop a denoising procedure enabling automated, efficient, and robust data enhancement. However, a fundamental problem is the lack of clean/denoised ground-truth samples. The current work is the first presenting a fully-automated deep denoising approach for bioacoustics, not requiring any clean ground-truth, together with one of the largest data archives recorded on killer whales ( Orcinus Orca) — the Orchive. Therefore, an approach, originally developed for image restoration, known as Noise2Noise (N2N), was transferred to the field of bioacoustics, and extended by using automatic machine-generated binary masks as additional network attention mechanism. Besides a significant cross-domain signal enhancement, our previous results regarding supervised orca/noise segmentation and orca call type identification were outperformed by applying ORCA-CLEAN as additional data preprocessing/enhancement step.