US 12,597,431 B1 · Noise suppression using subspace processing

Abstract

A system configured to perform noise suppression using subspace processing. For example, a device may estimate a multichannel noise subspace and use the estimated noise subspace to perform noise suppression while preserving coherence between microphones, enabling further processing (e.g., beamforming, SSL processing). The device may estimate the noise subspace during non-speech activity to determine a set of principal noise components in each frequency band. In some examples, the device may perform time-varying principal component analysis (PCA) processing to adaptively estimate the noise subspace. For example, the device may determine a noise matrix, estimate the noise subspace using dominant eigenvectors of the noise matrix, project the input noisy observations onto the null space of noise to determine a noise estimate and perform noise suppression. To reduce signal distortion, the device may use a signal quality metric as a proxy for speech detection and vary an amount of noise suppression accordingly.

Claims19

Dependent claims

A computer-implemented method, the method comprising:

determining first audio data including a first representation of an audible sound and a first representation of noise, the first audio data corresponding to a plurality of microphones;
determining, using the first audio data, first signal quality metric data;
determining, using the first signal quality metric data, first data;
determining, using the first audio data and the first data, second data corresponding to the noise, the second data comprising a plurality of components;
determining, using the second data, first vector data representing a subset of the plurality of components, the first vector data corresponding to the plurality of microphones;
determining, using the first vector data and the first audio data, second audio data including a second representation of the noise;
determining, using the first audio data and the second audio data, third audio data including a second representation of the audible sound,
determining, using the second audio data, estimated noise floor data;
and
determining third data using the first signal quality metric data, the second audio data, and the estimated noise floor data, the third data corresponding to a target amount of noise suppression.

7 more elements

A system comprising:

at least one processor;
and
memory including instructions operable to be executed by the at least one processor to cause the system to:
determine first audio data including a first representation of an audible sound and a first representation of noise, the first audio data corresponding to a plurality of microphones;
determine, using the first audio data, first signal quality metric data;
determine, using the first signal quality metric data, first data;
determine, using the first audio data and the first data, second data corresponding to the noise, the second data comprising a plurality of components;
determine, using the second data, first vector data representing a subset of the plurality of components, the first vector data corresponding to the plurality of microphones;
determine, using the first vector data and the first audio data, second audio data including a second representation of the noise;
determine, using the second audio data and first weight values associated with an adaptive filter, third audio data including a third representation of the noise;
determine, using the first audio data and the third audio data, fourth audio data including a second representation of the audible sound;
and
determine, using the third audio data and the fourth audio data, second weight values associated with the adaptive filter.

10 more elements

Dependencies are inferred from the claim text.

Noise suppression using subspace processing

Life of this patent

Noise suppression using subspace processing

Life of this patent

Abstract

Claims19