| 摘要 |
A method is disclosed for discriminating voiced and unvoiced sounds in speech. The method detects characteristic waveform features of voiced and unvoiced sounds, by applying integral and differential functions to the digitized sound signal in the time domain. Laboratory tests demonstrate extremely high reliability in separating voiced and unvoiced sounds. The method is very fast and computationally efficient. The method enables voice activation in resource-limited and battery-limited devices, including mobile devices, wearable devices, and embedded controllers. The method also enables reliable command identification in applications that recognize only predetermined commands. The method is suitable as a pre-processor for natural language speech interpretation, improving recognition and responsiveness. The method enables realtime coding or compression of speech according to the sound type, improving transmission efficiency. |
| 主权项 |
1. A method for indicating when voiced sounds or unvoiced sounds are present in speech sounds, said method comprising:
converting, with an analog-to-digital converter, the speech sounds to a speech signal comprising sequential digitized values; integrating the speech signal, thereby generating an integral signal; differentiating the speech signal, thereby generating a differential signal; subtracting the integral signal from the speech signal, thereby producing a speech-minus-integral signal; subtracting the differential signal from the speech signal, thereby producing a speech-minus-differential signal; differentiating the speech-minus-integral signal, thereby producing a refined differential signal; integrating the speech-minus-differential signal, thereby producing a refined integral signal; when the refined integral signal exceeds a refined-integral-signal threshold, generating a first output signal, thereby indicating that a voiced sound is present; and when the refined differential signal exceeds a refined-differential-signal threshold, generating a second output signal, thereby indicating that an unvoiced sound is present. |
