Globally optimized least-squares post-filtering for speech enhancement

An apparatus, comprising:

• one or more processing devices and one or more storage devices storing instructions that, when executed by the one or more processing devices, cause the one or processing devices to:
• receive audio signals via a microphone array from sound sources in an environment;
• hypothesize sound field scenarios to generate multiple output signals, including hypothesizing a point interferer, diffuse noise, and white noise, based on the received audio signals;
• calculate fixed beamformer coefficients based on the received audio signals;
• determine covariance matrix models based on the multiple output signals;
• calculate a covariance matrix based on the received audio signals;
• estimate power of the sound sources to find a solution that minimizes the difference between the determined covariance matrix models and the calculated covariance matrix;
• calculate and applying post-filter coefficients based on the estimated power;
• and
• generate an output audio signal based on the received audio signals and the post-filter coefficients.

A non-transitory computer-readable medium, comprising sets of instructions for:

• receiving audio signals via a microphone array from sound sources in an environment;
• hypothesizing sound field scenarios to generate multiple output signals, including hypothesizing a point interferer, diffuse noise, and white noise, based on the received audio signals;
• calculating fixed beamformer coefficients based on the received audio signals;
• determining covariance matrix models based on the multiple output signals;
• calculating a covariance matrix based on the received audio signals;
• estimating power of the sound sources to find a solution that minimizes the difference between the determined covariance matrix models and the calculated covariance matrix;
• calculating and applying post-filter coefficients based on the estimated power;
• and
• generating an output audio signal based on the received audio signals and the post-filter coefficients.