Low complexity detection of voiced speech and pitch estimation

US11176957B2 · kind B2 · utility

Assignee

• CERENCE OPERATING COMPANY · US

Inventors

• Simon Graf · Ulm, DE
• Tobias Herbig · Ulm, DE
• Markus Buck · Biberach, DE

Key dates

• Filing date: Aug 17, 2017
• Grant date: Nov 16, 2021
• Expiry date: Aug 28, 2037

Classification

• Technology area (CPC G): Physics
• CPC primary: G10L25/93
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A low-complexity method and apparatus for detection of voiced speech and pitch estimation is disclosed that is capable of dealing with special constraints given by applications where low latency is required, such as in-car communication (ICC) systems. An example embodiment employs very short frames that may capture only a single excitation impulse of voiced speech in an audio signal. A distance between multiple such impulses, corresponding to a pitch period, may be determined by evaluating phase differences between low-resolution spectra of the very short frames. An example embodiment may perform pitch estimation directly in a frequency domain based on the phase differences and reduce computational complexity by obviating transformation to a time domain to perform the pitch estimation. In an event the phase differences are determined to be substantially linear, an example embodiment enhances voice quality of the voiced speech by applying speech enhancement to the audio signal.