Patent ID: 8913737

Claim:
An echo canceller for executing adaptive processing for canceling an echo component mixed with an audio input signal, comprising: a volume ratio learner configured to compute a volume ratio in each of a plurality of predetermined frequency ranges between an audio output signal externally outputted and said audio input signal mixed with an echo component caused by reflection of said audio output signal to said audio input signal, thereby learning said volume ratio in a regular status in own apparatus, wherein the volume ratio, which is computed for each of the plurality of predetermined frequency ranges, the plurality of predetermined frequency ranges composing entire frequency region, is computed between a maximum value of the audio output signal in the corresponding frequency range and a maximum value of the audio input signal mixed with the echo component in the corresponding frequency range; a double-talk detector configured to detect said double-talk status depending on whether a this-time volume ratio computed this time adapts to a double-talk status predicted by said learning of volume ratio based on a volume ratio range of a single-talk status learned by the volume ratio learner, wherein said double-talk detector divides said audio input signal and said audio output signal each into the plurality of predetermined frequency ranges composing the entire frequency region to execute the processing on a predetermined frequency range basis; and an echo cancel processor configured to control a learning operation of said echo component for said adaptive processing on the basis of a result of said double-talk status detection by said double-talk detector.