A two-member research team from the Indian Institute of Science (IISc) has developed a method to detect whispered speech even in a noisy recording.
Researchers say further research on the finding by G Nisha Meenakshi and Prasanta Kumar Ghosh of the Department of Electrical Engineering, IISc, could help reconstruct normal speech in people with laryngeal (voice box) cancer.
Meenakshi said, “Many cases of laryngeal cancer require surgical removal of the voice box. A laryngectomy patient’s speech is typically whispered. A device which reconstructs normal speech from whispered speech could render voice to these patients.”
In a note, the researchers explained that voice activity detection was applied in a variety of speech communication systems, including speech recognition, audio conferencing, and echo cancellation.
It is also used to increase mobile phone longevity, by reducing the power lost by transmitting noise when no one is speaking.
Drawing a comparison between the whispered speech and a normal one, Meenakshi said that as there was no vibration of the vocal folds while whispering, the speech was more noise-like. This apart, even the shape of the frequency spectrum of whispered speech varied, she said.