In this paper, we introduce a non-voice rejection method to perform Voice/Non-Voice (V/NV) classification using a fundamental frequency (F0) estimator called YIN. Although current speech recognition technology has achieved high performance, it is insufficient for some applications where high reliability is required, such as voice control of powered wheelchairs for disabled persons. The non-voice rejection algorithm, which classifies V/NV in Voice Activity Detection (VAD) step, is helpful for realizing a highly reliable system. The proposed algorithm adopts the ratio of a reliable F0 contour to the whole input interval. To evaluate the performance of our proposed method, we used 1567 voice commands and 447 noises in powered wheelchair control in a real environment. These results indicate that the recall rate is 97% when the lowest threshold is selected for noise classification with 99% precision in VAD.
Bibliographic reference. Suk, Soo-Young / Kojima, Hiroaki (2007): "Voice activated powered wheelchair with non-voice rejection algorithm", In INTERSPEECH-2007, 2541-2544.