Abstract: A method for noise characteristic dependent speech enhancement by an electronic device is described. The method includes determining a noise characteristic of input audio. Determining a noise characteristic of input audio includes determining whether noise is stationary noise and determining whether the noise is music noise. The method also includes determining a noise reference based on the noise characteristic. Determining the noise reference includes excluding a spatial noise reference from the noise reference when the noise is stationary noise and including the spatial noise reference in the noise reference when the noise is not music noise and is not stationary noise. The method further includes performing noise suppression based on the noise characteristic.

Abstract: A method for multi-channel echo cancellation and noise suppression is described. One of multiple echo estimates is selected for non-linear echo cancellation. Echo notch masking is performed on a noise-suppressed signal based on an echo direction of arrival (DOA) to produce an echo-suppressed signal. Non-linear echo cancellation is performed on the echo-suppressed signal based, at least in part, on the selected echo estimate.

Abstract: Systems, methods, apparatus, and machine-readable media for detecting head movement based on recorded sound signals are described.

Abstract: Apparatus and methods for audio noise attenuation are disclosed. An audio signal analyzer can determine whether an input audio signal received from a microphone device includes a noise signal having identifiable content. If there is a noise signal having identifiable content, a content source is accessed to obtain a copy of the noise signal. An audio canceller can generate a processed audio signal, having an attenuated noise signal, based on comparing the copy of the noise signal to the input audio signal. Additionally or alternatively, data may be communicated on a communication channel to a separate media device to receive at least a portion of the copy of the noise signal from the separate media device, or to receive content-identification data corresponding to the content source.

Abstract: Systems, methods, and apparatus for spectral contrast enhancement of speech signals, based on information from a noise reference that is derived by a spatially selective processing filter from a multichannel sensed audio signal, are disclosed.

Abstract: A method for echo cancellation and noise suppression is disclosed. Linear echo cancellation (LEC) is performed for a primary microphone channel on an entire frequency band or in a range of frequencies where echo is audible. LEC is performed on one or more secondary microphone channels only on a lower frequency range over which spatial processing is effective. The microphone channels are spatially processed over the lower frequency range after LEC. Non-linear noise suppression post-processing is performed on the entire frequency band. Echo post-processing is performed on the entire frequency band.

Abstract: Decomposition of a multi-source signal using a basis function inventory and a sparse recovery technique is disclosed.

Abstract: Based on phase differences between corresponding frequency components of different channels of a multichannel signal, a measure of directional coherency is calculated. Application of such a measure to voice activity detection and noise reduction are also disclosed.

Abstract: A method includes, while operating an audio processing device in a use mode, retrieving first direction of arrival (DOA) data corresponding to a first audio output device from a memory of the audio processing device and generating a first null beam directed toward the first audio output device based on the first DOA data. The method also includes retrieving second DOA data corresponding to a second audio output device from the memory of the audio processing device and generating a second null beam directed toward the second audio output device based on the second DOA data. The first DOA data and the second DOA data are stored in the memory during operation of the audio processing device in a calibration mode.

Abstract: A method for echo reduction by an electronic device is described. The method includes nulling at least one speaker. The method also includes mixing a set of runtime audio signals based on a set of acoustic paths to determine a reference signal. The method also includes receiving at least one composite audio signal that is based on the set of runtime audio signals. The method further includes reducing echo in the at least one composite audio signal based on the reference signal.

Abstract: Phase-based processing of a multichannel signal, and applications including proximity detection, are disclosed.

Abstract: Systems, methods, and apparatus for pitch trajectory analysis are described. Such techniques may be used to remove vocals and/or vibrato from an audio mixture signal. For example, such a technique may be used to pre-process the signal before an operation to decompose the mixture signal into individual instrument components.

Abstract: A mobile platform includes a microphone array and is capable of implementing beamforming to amplify or suppress audio information from a sound source. The sound source is indicated through a user input, such as pointing the mobile platform in the direction of the sound source or through a touch screen display interface. The mobile platform further includes orientation sensors capable of detecting movement of the mobile platform. When the mobile platform moves with respect to the sound source, the beamforming is adjusted based on the data from the orientation sensors so that beamforming is continuously implemented in the direction of the sound source. The audio information from the sound source may be included or suppressed from a telephone or video-telephony conversation. Images or video from a camera may be likewise controlled based on the data from the orientation sensors.

Abstract: A method for encoding multiple directional audio signals using an integrated codec by a wireless communication device is disclosed. The wireless communication device records a plurality of directional audio signals. The wireless communication device also generates a plurality of audio signal packets based on the plurality of directional audio signals. At least one of the audio signal packets includes an averaged signal. The wireless communication device further transmits the plurality of audio signal packets.

Abstract: A method for encoding three dimensional audio by a wireless communication device is disclosed. The wireless communication device detects an indication of a plurality of localizable audio sources. The wireless communication device also records a plurality of audio signals associated with the plurality of localizable audio sources. The wireless communication device also encodes the plurality of audio signals.

Abstract: A system which performs social interaction analysis for a plurality of participants includes a processor. The processor is configured to determine a similarity between a first spatially filtered output and each of a plurality of second spatially filtered outputs. The processor is configured to determine the social interaction between the participants based on the similarities between the first spatially filtered output and each of the second spatially filtered outputs and display an output that is representative of the social interaction between the participants. The first spatially filtered output is received from a fixed microphone array, and the second spatially filtered outputs are received from a plurality of steerable microphone arrays each corresponding to a different participant.

Abstract: Disclosed is an application interface that takes into account the user's gaze direction relative to who is speaking in an interactive multi-participant environment where audio-based contextual information and/or visual-based semantic information is being presented. Among these various implementations, two different types of microphone array devices (MADs) may be used. The first type of MAD is a steerable microphone array (a.k.a. a steerable array) which is worn by a user in a known orientation with regard to the user's eyes, and wherein multiple users may each wear a steerable array. The second type of MAD is a fixed-location microphone array (a.k.a. a fixed array) which is placed in the same acoustic space as the users (one or more of which are using steerable arrays).

Abstract: A system which tracks a social interaction between a plurality of participants, includes a fixed beamformer that is adapted to output a first spatially filtered output and configured to receive a plurality of second spatially filtered outputs from a plurality of steerable beamformers. Each steerable beamformer outputs a respective one of the second spatially filtered outputs associated with a different one of the participants. The system also includes a processor capable of determining a similarity between the first spatially filtered output and each of the second spatially filtered outputs. The processor determines the social interaction between the participants based on the similarity between the first spatially filtered output and each of the second spatially filtered outputs.

Abstract: A method for restoring a processed speech signal by an electronic device is described. The method includes obtaining at least one audio signal. The method also includes performing bin-wise voice activity detection based on the at least one audio signal. The method further includes restoring the processed speech signal based on the bin-wise voice activity detection.

Abstract: A method for signal level matching by an electronic device is described. The method includes capturing a plurality of audio signals from a plurality of microphones. The method also includes determining a difference signal based on an inter-microphone subtraction. The difference signal includes multiple harmonics. The method also includes determining whether a harmonicity of the difference signal exceeds a harmonicity threshold. The method also includes preserving the harmonics to determine an envelope. The method further applies the envelope to a noise-suppressed signal.