Double talk detection using capture up-sampling
AssigneeDolby Laboratories Licensing Corporation
InventorNing Wang
Life of this patent
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Abstract
A method of double talk detection includes using up-sampling. Audio signals received from the far end are up-sampled prior to output by the loudspeaker at the near end. The microphone at the near end captures audio at the up-sampled rate, and the audio output by the loudspeaker is detectable due to having no energy in the up-sampled frequency bands. The double talk detector uses this information to generate a signal for suppressing the echo of the far end audio from the captured audio signal that is transmitted to the far end.
Claims20
A computer-implemented method of audio processing, the method comprising:
- receiving a first audio signal, wherein the first audio signal has a first sampling frequency;
- up-sampling the first audio signal to generate a second audio signal, wherein the second audio signal has a second sampling frequency that is greater than the first sampling frequency;
- outputting, by a loudspeaker, a loudspeaker output corresponding to the second audio signal;
- capturing, by a microphone, a third audio signal, wherein the third audio signal is sampled at the second sampling frequency;
- determining a signal power of the third audio signal;
- and
- detecting double talk when there is signal power of the third audio signal determined in a frequency band having frequencies all greater than half the first sampling frequency.
An apparatus for audio processing, the apparatus comprising:
- a loudspeaker;
- a microphone;
- and
- a processor;
- wherein the processor is configured to control the apparatus to receive a first audio signal, wherein the first audio signal has a first sampling frequency;
- wherein the processor is configured to control the apparatus to up-sample the first audio signal to generate a second audio signal, wherein the second audio signal has a second sampling frequency that is greater than the first sampling frequency;
- wherein the processor is configured to control the apparatus to output, by the loudspeaker, a loudspeaker output corresponding to the second audio signal;
- wherein the processor is configured to control the apparatus to capture, by the microphone, a third audio signal, wherein the third audio signal is sampled at the second sampling frequency;
- wherein the processor is configured to control the apparatus to determine a signal power of the third audio signal;
- and
- wherein the processor is configured to control the apparatus to detect double talk when there is signal power of the third audio signal determined in a frequency band having frequencies all greater than half the first sampling frequency.
Dependencies are inferred from the claim text.