@article {50905, title = {Frog sound identification using extended k-nearest neighbor classifier}, journal = {Journal of Physics: Conference Series}, volume = {890}, year = {2017}, month = {Jan-09-2017}, pages = {012070}, abstract = {

Frog sound identification based on the vocalization becomes important for biological research and environmental monitoring. As a result, different types of feature extractions and classifiers have been employed to evaluate the accuracy of frog sound identification. This paper presents a frog sound identification with Extended k-Nearest Neighbor (EKNN) classifier. The EKNN classifier integrates the nearest neighbors and mutual sharing of neighborhood concepts, with the aims of improving the classification performance. It makes a prediction based on who are the nearest neighbors of the testing sample and who consider the testing sample as their nearest neighbors. In order to evaluate the classification performance in frog sound identification, the EKNN classifier is compared with competing classifier, k -Nearest Neighbor (KNN), Fuzzy k -Nearest Neighbor (FKNN) k - General Nearest Neighbor (KGNN)and Mutual k -Nearest Neighbor (MKNN) on the recorded sounds of 15 frog species obtained in Malaysia forest. The recorded sounds have been segmented using Short Time Energy and Short Time Average Zero Crossing Rate (STE+STAZCR), sinusoidal modeling (SM), manual and the combination of Energy (E) and Zero Crossing Rate (ZCR) (E+ZCR) while the features are extracted by Mel Frequency Cepstrum Coefficient (MFCC). The experimental results have shown that the EKNCN classifier exhibits the best performance in terms of accuracy compared to the competing classifiers, KNN, FKNN, GKNN and MKNN for all cases.

}, issn = {1742-6588}, doi = {10.1088/1742-6596/890/1/012070}, url = {http://stacks.iop.org/1742-6596/890/i=1/a=012070?key=crossref.393dd3e387b6a34eb3971240d516f44b}, author = {Mukahar, Nordiana and Rosdi, Bakhtiar Affendi and Ramli, Dzati Athiar and Jaafar, Haryati} } @article {47889, title = {Automatic recognition of animal vocalizations using averaged MFCC and linear discriminant analysis}, journal = {Pattern Recognition Letters}, volume = {27}, year = {2006}, month = {Jan-01-2006}, pages = {93 - 101}, abstract = {

In this paper we propose a method that uses the averaged Mel-frequency cepstral coefficients (MFCCs) and linear discriminant anal- ysis (LDA) to automatically identify animals from their sounds. First, each syllable corresponding to a piece of vocalization is segmented. The averaged MFCCs over all frames in a syllable are calculated as the vocalization features. Linear discriminant analysis (LDA), which finds out a transformation matrix that minimizes the within-class distance and maximizes the between-class distance, is utilized to increase the classification accuracy while to reduce the dimensionality of the feature vectors. In our experiment, the average classification accuracy is 96.8\% and 98.1\% for 30 kinds of frog calls and 19 kinds of cricket calls, respectively.

}, keywords = {linear discriminant analysis, Mel-frequency cepstral coefficients}, issn = {01678655}, doi = {10.1016/j.patrec.2005.07.004}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0167865505001959}, author = {Lee, Chang-Hsing and Chou, Chih-Hsun and Han, Chin-Chuan and Huang, Ren-Zhuang} } @article {47327, title = {The use of bioacoustics in anuran taxonomy: theory, terminology, methods and recommendations for best practice}, journal = {Zootaxa}, volume = {4251}, year = {2017}, month = {Nov-04-2017}, pages = {1}, abstract = {

Vocalizations of anuran amphibians have received much attention in studies of behavioral ecology and physiology, but also provide informative characters for identifying and delimiting species. We here review the terminology and variation of frog calls from a perspective of integrative taxonomy, and provide hands-on protocols for recording, analyzing, comparing, interpreting and describing these sounds. Our focus is on advertisement calls, which serve as premating isolation mechanisms and, therefore, convey important taxonomic information. We provide recommendations for terminology of frog vocalizations, with call, note and pulse being the fundamental subunits to be used in descriptions and comparisons. However, due to the complexity and diversity of these signals, an unequivocal application of the terms call and note can be challenging. We therefore provide two coherent concepts that either follow a note-centered approach (defining uninterrupted units of sound as notes, and their entirety as call) or a call-centered approach (defining uninterrupted units as call whenever they are separated by long silent intervals) in terminology. Based on surveys of literature, we show that numerous call traits can be highly variable within and between individuals of one species. Despite idiosyncrasies of species and higher taxa, the duration of calls or notes, pulse rate within notes, and number of pulses per note appear to be more static within individuals and somewhat less affected by temperature. Therefore, these variables might often be preferable as taxonomic characters over call rate or note rate, which are heavily influenced by various factors. Dominant frequency is also comparatively static and only weakly affected by temperature, but depends strongly on body size. As with other taxonomic characters, strong call divergence is typically indicative of species-level differences, whereas call similarities of two populations are no evidence for them being conspecific. Taxonomic conclusions can especially be drawn when the general advertisement call structure of two candidate species is radically different and qualitative call differences are thus observed. On the other hand, quantitative differences in call traits might substantially vary within and among conspecific populations, and require careful evaluation and analysis. We provide guidelines for the taxonomic interpretation of advertisement call differences in sympatric and allopatric situations, and emphasize the need for an integrative use of multiple datasets (bio-acoustics, morphology, genetics), particularly for allopatric scenarios. We show that small-sized frogs often emit calls with frequency components in the ultrasound spectrum, although it is unlikely that these high frequencies are of biological relevance for the majority of them, and we illustrate that detection of upper harmonics depends also on recording distance because higher frequencies are attenuated more strongly. Bioacoustics remains a prime approach in integrative taxonomy of anurans if uncertainty due to possible intraspecific variation and technical artifacts is adequately considered and acknowledged.

}, keywords = {Amphibia, Anura, call, call analysis, call description, call variation, definitions, note, pulse, sound, species delimitation, taxonomy, vocalization}, issn = {1175-5326}, doi = {10.11646/zootaxa.4251.110.11646/zootaxa.4251.1.1}, url = {http://biotaxa.org/Zootaxa/issue/view/zootaxa.4251.1}, author = {J{\"o}rn K{\"o}hler and Martin Jansen and Ariel Rodr{\'\i}guez and Philippe J. R. Kok and Lu{\'\i}s Felipe Toledo and Emmrich, Mike and Frank Glaw and C{\'e}lio F. B. Haddad and Mark-Oliver R{\"o}del and Miguel Vences} }