Audio processing apparatus and method

An audio processing apparatus, comprising:

• a main microphone for receiving sounds from a source and noises from non-source sources and generating a main input;
• a reference microphone for receiving the sounds and the noises and generating a reference input;
• a short-time Fourier transformation (STFT) unit for applying short time Fourier transformation to convert the main input of a time domain signals into a main signal of a frequency domain and convert the reference input of the time domain signals into a reference signal of the frequency domain;
• a sensitivity calibrating unit for performing sensitivity calibration on the main signal and the reference signal and generating a main calibrated signal and a reference calibrated signal;
• a voice active detector (VAD) for generating a voice active signal according to the main calibrated signal, the reference calibrated signal and a direction of arrival (DOA) signal;
• and
• a beamformer for converting the main calibrated signal into a main channel and converting the reference calibrated signal into a reference channel according to the voice active signal.