US Patent 9094749 Head-mounted sound capture device

A platform that is configured to be removably placed symmetrically on or about a user's head has at least a first transducer configured to capture vibration of the user's skull or facial movement generated by the user's voice activity and to detect the user's speaking activity. This first transducer converts the vibration or facial movement into a first electrical audio signal. The electrical audio signal from the first transducer is processed by circuitry or embodied software as voiced frames and/or as unvoiced frames, in which the voiced frames and/or the unvoiced frames are defined based at least on the first electrical audio signal. Multiple embodiments follow from this: where the first transducer is a vibration sensor; where voice is captured by an air microphone and filtering adaptation differs for the voiced versus unvoiced frames as defined by the first transducer, and another with at least three air microphones.