Contour extraction algorithm for the automated photo-identification of dolphins

The photo-identification of individuals within an animal population is an important objective for the description of the environment itself, for studies relating to the distribution of species and their habitat-use as well as their conservation. The manual analysis of the photos collected by experts is generally very expensive in terms of time and requires specific knowledge. In the field of cetology, photo-identification based on the dorsal fin of individuals is widespread. The software here presented aims to effectively isolate the outline of the dorsal fin, so that it can be used in applications that exploit nicks, notches and other irregularities for the identification and classification process. It implements a series of innovative and specific operations that make the tool applicable to very large datasets with good performances and it has been successfully used for the extraction of the fin outline on dolphin images acquired in the Gulf of Taranto (Northern Ionian Sea - Central Mediterranean Sea).