Automatic Frame Length, Frame Overlap and Hidden Markov Model Topology for Speech Recognition of Animal Vocalizations

Preface Automatic Speech Recognition (ASR) is a useful tool that can facilitate the research and study of animal vocalizations. The use of human speech-based signal processing techniques for animal vocalizations has several pitfalls. Animal vocalizations may not share the same spectral or temporal characteristics as human speech. As a result , the typical ASR assumptions concerning the best frame length, frame overlap and HMM topology may not be suitable for various animal vocalizations. This paper proposes a technique for estimating the frame length, frame overlap and HMM topol-ogy from a single, clean, example animal vocalization. Multiple trials are run using the proposed technique, against the vocalizations of two distinct animal species: the Norwegian Ortolan Bunting (Emberiza Hortulana) and the African Elephant (Lox-odonta Africana). The results are examined, and the technique provides reasonable estimates for the frame length, the frame overlap and the HMM topology, given the quality of the example vocalizations. Specific recommendations are made for the continuation of this research into a usable tool for animal researches. ii Acknowledgments I thank all of the people that made this work possible; including, but not limited to, the following people: To my wife, Denise, for her love and support and for graciously accepting my absence from our living room every evening for the last year. To my children, Logan and Zoe, for gracing our lives. To my parents, James and Kathleen, and to the Holy Trinity, for providing me with the gifts that make my life's work possible. Finally, I thank Sun Tzu, for teaching me how to live purposefully: " Withdraw like a mountain in movement, advance like a rainstorm. Strike and crush with shattering force; go into battle like a tiger. " [1] iii iv I dedicate this work to my wife Denise, my son Logan and my daughter Zoe, whom are living examples of courage, unbounded energy and enthusiasm, respectively.