Method and apparatus for audio capture using beamforming

An apparatus for capturing audio, the apparatus comprising:

• a microphone array;
• a first beamformer, the beamformer coupled to the microphone array, wherein the beamformer is arranged to generate a first beamformed audio output;
• a plurality of constrained beamformers, the plurality of constrained beamformers coupled to the microphone array, wherein each of the plurality of constrained beamformers is arranged to generate a constrained beamformed audio output;
• a first adapter, wherein the first adaptor is arranged to adapt beamform parameters of the first beamformer;
• a second adapter, wherein the second adaptor is arranged to adapt constrained beamform parameters for the plurality of constrained beamformers;
• a difference processor circuit, wherein the difference processor circuit is arranged to determine a difference measure for at least one of the plurality of constrained beamformers,
• wherein the difference measure is indicative of a difference between beams formed by the first beamformer and the at least one of the plurality of constrained beamformers;
• wherein the second adapter is arranged to adapt constrained beamform parameters with a constraint such that constrained beamform parameters are adapted only for constrained beamformers of the plurality of constrained beamformers for which a difference measure has been determined that meets a similarity criterion,
• wherein the difference processor circuit is arranged to determine the difference measure for a first constrained beamformer as a difference between a first set of parameters and the constrained set of parameters for the first constrained beamformer.