Abstract:
A headset is constructed to generate an acoustically distinct speech signal in a noisy acoustic environment. The headset positions a pair of spaced-apart microphones near a user's mouth. The microphones each receive the user s speech, and also receive acoustic environmental noise. The microphone signals, which have both a noise and information component, are received into a separation process. The separation process generates a speech signal that has a substantial reduced noise component. The speech signal is then processed for transmission. In one example, the transmission process includes sending the speech signal to a local control module using a Bluetooth radio.
Abstract:
Acoustic noise suppression is provided in multiple-microphone systems using Voice Activity Detectors (VAD). A host system receives acoustic signals via multiple microphones. The system also receives information on the vibration of human tissue associated with human voicing activity via the VAD. In response, the system generates a transfer function representative of the received acoustic signals upon determining that voicing information is absent from the received acoustic signals during at least one specified period of time. The system removes noise from the received acoustic signals using the transfer function, thereby producing a denoised acoustic data stream.
Abstract:
A method and system are provided for acoustic noise removal from human speech, wherein noise is removed without respect to noise type, amplitude, or orientation. The system includes microphones and a voice activity detection (VAD) data stream coupled among a processor. The microphones receive acoustic signals and the VAD produces a signal including a binary one when speech (voiced and unvoiced) is occurring and a binary zero in the absence of speech. The processor includes denoising algorithms that generate transfer functions. The transfer functions include a transfer function generated in response to a determination that voicing information is absent from the received acoustic signal during a specified time period. The transfer functions also include transfer functions generated in response to a determination that voicing information is present in the acoustic signal during a specified time period. At least one denoised acoustic data stream is generated using the transfer functions.
Abstract:
The subject of the invention is a signal cleaning procedure to isolate audio-frequency signals from the background noise. During the procedure, the signal to be cleaned is led into a filter bank and the signals separated into sub-bands will be sent into a transformer unit where a transformation will be performed upon them and this way a cleaned signal will be produced. It is a typical feature of the procedure that the instantaneous amplitude or the approximated value of the amplitude of the signal of each sub-band appearing at the output (1a) of the filter bank (1) is produced first in the transformer unit, then the instantaneous amplitude values produced this way will be averaged and the signals of the sub-bands will be weighted using the averages, and finally the weighted signals will be summed up and the cleaned signal will be determined this way.
Abstract:
In a method of improving the intelligibility of a first sound signal (S0) having a certain frequency spectrum, at least one additional sound signal (S1; S1, S2, ..., Sn) is generated comprising a transposition of the spectrum of the first signal in frequency. A combined signal (S+) is generated comprising the first signal (S0) as well as the at least one additional signal (S1; S1, S2, ..., Sn), and the combined signal is reproduced to a user. In this way the intelligibility of a sound signal is improved, while it is still possible to recognize the original sound of a speaker. The natural sound of the speaker is maintained due to the fact that the original sound signal is still contained in the resulting signal. Due to the additional signals the resulting signal will probably also contain speech information in a frequency band in which the person has a better perception.
Abstract:
Disclosed are a multi-microphone noise reduction method, an apparatus and a terminal device. The method includes: performing harmonic detection on a primary microphone signal to obtain frequency bin VAD flag information; controlling, according to the frequency bin VAD flag information, a Kalman filter to filter out a target speech signal from a secondary microphone signal, to obtain a secondary microphone noise signal; mapping the secondary microphone noise signal to the primary microphone signal through dynamic noise spectrum mapping, to obtain a primary microphone noise spectrum of the primary microphone signal; and calculating a noise reduction gain for the primary microphone signal according to at least the primary microphone noise spectrum of the primary microphone signal, and outputting a noise-reduced primary speech signal. The method has good robustness to location changes, various noises and application scenarios, and can be applied to both the handheld and hands-free modes.
Abstract:
A method of operation of a device includes receiving an input signal at the device. The input signal is generated using at least one microphone. The input signal includes a first signal component having a first amount of wind turbulence noise and a second signal component having a second amount of wind turbulence noise that is greater than the first amount of wind turbulence noise. The method further includes generating, based on the input signal, an output signal at the device. The output signal includes the first signal component and a third signal component that replaces the second signal component. A first frequency response of the input signal corresponds to a second frequency response of the output signal.