Research on Tone Features of Chinese Vowel Whispers

In terms of the special pronunciation, the pitch frequency, which is the tone carrier of the whispers, is lost. As a tone language, speaker’s meaning may be mostly expressed through the tone of mandarin. So the tone character extracting is the important step of whisper speech processing. The traditional characters, which are used in speech recognition or speaker identification, mostly contained the voice meaning or speaker’s information, so few conventional characters is suitable for whisper tong recognition experiments. A new parameter which may express the whisper tone is discovered during many analysis experiments. Tone information is not a strong signal, so it may not be showed in full frequency domain. Based on the human’s auditory ability, whisper tone information may be delivered through some of the sensitive bark band. The fitting curve of energy proportion of diffused Bark spectrum can replace the pitch frequency track of normal speech to some extent, and it can be the new carrier of whisper tone information. The average correct rate is 78% in mandarin tone recognition experiments, when use the fitting curve and the short-time energy as the characters, and the neural network as the model. And it provides the foundation of deeper study in whisper speech processing field.