Characterization of Spoken English Vowels Using Tree Structures

Characterization of vowels in spoken English plays a significant role in designing speech processing systems. In this work, spoken English vowels are analysed to find features which can help in their characterization. The outcome of the analysis led to the proposal of a novel feature which uses tree structures for the representation of vowels. In this approach, the vowels are represented as trees with their structural properties being elements in the trees. These properties are extracted by understanding the geometrical shapes of acoustic events. To prove the features that they can distinguish between vowels, a comparison is shown by calculating the distances among the new features. The computation of distance is done by employing a tree matching algorithm. The performance of the proposed features are compared against the standard MFCC features. In the analysis, speech data of Indian native speakers was used. The analysis procedures and the results obtained are presented.