System and Method for Acoustic Echo Cancellation
AssigneeInteractive Intelligence, Inc.
InventorsFelix Immanuel Wyss, Rivarol Vergin, Ananth Nagaraja Iyer, Aravind Ganapathiraju, Kevin Charles Vlack, Srinath Cheluvaraja
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Abstract
A system and method are presented for acoustic echo cancellation. The echo canceller performs reduction of acoustic and hybrid echoes which may arise in a situation such as a long-distance conference call with multiple speakers in varying environments, for example. Echo cancellation, in at least one embodiment, may be based on similarity measurement, statistical determination of echo cancellation parameters from historical values, frequency domain operation, double talk detection, packet loss detection, signal detection, and noise subtraction.
Claims63
A system for cancellation of acoustic echo comprising:
- a. means for audio input;
- b. means for generating an audio signal from said audio input;
- c. means for transmitting said audio signal;
- d. means for converting said audio signal into a frequency domain;
- e. means for performing similarity measure;
- f. means for performing delay estimation;
- g. means for performing echo parameter estimation;
- h. means for performing statistical echo validation;
- i. means for detecting speech;
- and
- j. means for detecting double-talk.
A method for acoustic echo cancellation comprising the steps of:
- a. initializing echo model parameters;
- b. analyzing audio for speech;
- c. determining if speech has been detected, wherein if speech has not been detected, continuing to analyze said audio for speech;
- d. estimating echo delay and validating an echo model if speech has been detected;
- e. determining if echo is present, wherein if echo is not present, continuing to analyze audio for speech before continuing the process and repeating the process from step (c);
- f. determining if double talk is present, wherein if double talk is present, computing parameters for echo with double talk and if double talk is not present, computing parameters for regular echo;
- g. performing echo subtraction;
- h. tracking echo and updating said echo model;
- and
- i. determining if echo is still present, wherein:
- i. if echo is not present, starting the method anew;
- and
- ii. if echo is present, repeating the method beginning with step f).
A system for the cancellation of acoustic echo over communication networks comprising:
- a. means for audio input;
- b. means for generating an audio signal from said audio input;
- c. means for transmitting said audio signal;
- d. means for converting said audio signal from a time domain into a frequency domain;
- e. means for performing one or more of:
- similarity measure and delay estimation, statistical echo validation, and echo parameter estimation;
- f. means for detecting speech;
- and
- g. means for detecting double-talk.
A method for acoustic echo cancellation comprising the steps of:
- a. transforming an audio signal;
- b. initializing echo model parameters;
- c. analyzing said audio signal for speech;
- d. detecting a presence of speech;
- e. estimating echo delay and validating said echo model;
- f. detecting the presence of echo;
- g. detecting the presence of double talk;
- h. computing parameters for at least one of:
- echo with double talk and echo;
- i. subtracting the echo from the audio signal;
- j. updating said echo model;
- and
- k. determining if the presence of echo is reduced.
Dependencies are inferred from the claim text.