Voice activity detection method and device

US6374211B2 · kind B2 · utility

Assignee

• DEUTSCHE TELEKOM AG · DE

Inventors

• Joachim Stegmann · Darmstadt, DE
• Gerhard Schroeder · Krefeld, DE

Key dates

• Filing date: Apr 22, 1998
• Grant date: Apr 16, 2002
• Expiry date: Apr 22, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G10L25/27
• WIPO field: Computer technology
• WIPO sector: Electrical engineering

Abstract

A method and a circuit arrangement for automatic voice activity detection on the basis of the wavelet transformation. A voice activity detection circuit or module (5) is used to control a speech encoder (9) and a speech decoder (22), as well as a background noise encoder (10) and a background noise decoder (23) in order to perform source-controlled reduction of the mean transmission rate. After segmenting a speech signal, a wavelet transformation is computed for each frame, from which a set of parameters is determined, from which in turn a set of binary decision variables is calculated with the help of fixed thresholds in an arithmetic circuit (32). The decision variables control a decision logic circuit (42), whose result, after time smoothing in a time smoothing circuit (44), provides the statement “speech present/no speech” for each frame. The circuit itself includes segmenting circuit (28), a wavelet transformation circuit (30), an arithmetic circuit for the energy values (32), a pause detection circuit (34), a circuit for detecting stationary states (35), a first and a second background detector (36, 37), a downstream decision logic (42), and the circuit (44) for t…