| Entries |
| Document | Title | Date |
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| 20080212795 | Transient detection and modification in audio signals - A system and method are disclosed for transient detection and modification in audio signals. Digital signal processing techniques are used to detect transients and modify an audio signal to enhance or suppress such transients, as desired. A transient audio event is detected in a first portion of the audio signal. A graded response to the detected transient audio event is determined. The first portion of the audio signal is modified in accordance with the graded response. The extent of enhancement or suppression (as applicable) may be determined at least in part by a measure of the significance or magnitude of the transient. | 09-04-2008 |
| 20080219471 | SIGNAL PROCESSING METHOD AND APPARATUS, AND RECORDING MEDIUM IN WHICH A SIGNAL PROCESSING PROGRAM IS RECORDED - A signal processing method for converting a signal received via a transmission path or read from a storage medium into a first audible signal, and suppressing a noise other than a desired signal contained in the first audible signal based on predetermined audio quality adjustment information, comprising steps of: in suppressing a noise other than a desired signal contained in the first audible signal to generate an enhanced signal, receiving audio quality adjustment information for adjusting audio quality; and adjusting audio quality of the enhanced signal using the audio quality adjustment information | 09-11-2008 |
| 20080247569 | Noise Suppressing Apparatus and Program - A noise suppressing apparatus suppresses a noise component of a sound signal which contains the noise component and a signal component. In the apparatus, a frequency analyzing section divides the sound signal into a plurality of frames such that adjacent frames overlap with each other along a time axis, and computes a first spectrum of each frame. A noise suppressing section suppresses a noise component of the first spectrum so as to provide a second spectrum of each frame in which the noise component is suppressed. A frequency specifying section specifies a frequency of a noise component of each frame. A phase controlling section varies a phase of the noise component corresponding to the specified frequency in the second spectrum by a different variation amount each frame. A signal synthesizing section combines the frames after the second spectrum of each frame is processed by the phase controlling section, such that adjacent frames overlap with each other along the time axis so as to output the sound signal. | 10-09-2008 |
| 20080285773 | Adaptive LPC noise reduction system - A noise suppression system reduces low-frequency noise in a speech signal using linear predictive coefficients in an adaptive filter. A digital filter may update or adapt a limited set of linear predictive coefficients on a sample-by-sample basis. The linear predictive coefficients may be used to provide an error signal based on a difference between the speech signal and a delayed speech signal. The error signal represents an enhanced speech signal having attenuated and normalized low-frequency noise components. | 11-20-2008 |
| 20080304679 | SYSTEM FOR PROCESSING AN ACOUSTIC INPUT SIGNAL TO PROVIDE AN OUTPUT SIGNAL WITH REDUCED NOISE - An apparatus processes an acoustic input signal to provide an output signal with reduced noise. The apparatus weights the input signal based on a frequency-dependent weighting function. A frequency-dependent threshold function bounds the weighting function from below. | 12-11-2008 |
| 20090074203 | METHOD OF ENHANCING SOUND FOR HEARING IMPAIRED INDIVIDUALS - A portable assistive listening system for enhancing sound for hearing impaired individuals includes a functional hearing aid and a separate handheld digital signal processing (DSP) device. The focus of the embodiments is directed to the handheld DSP device and a method of processing audio signals. The DSP device includes a programmable digital signal processor, a UWB transceiver for communicating with the hearing aid and/or other wireless audio sources, an LCD display, and a user input device (keypad). The handheld device is user programmable to apply different sound processing algorithms for processing sound signals received from the hearing aid and/or other audio source. The handheld device is capable of receiving audio signals from multiple sources, and gives the user control over selection of incoming sound sources and selective processing of audio. In the context of being user programmable, the digital signal processing device includes a software platform that provides for the ability of the user to select, or plug-in, desired processing algorithms for application to selected incoming audio signals. The software embodiments include a method of pre-analyzing multiple incoming audio signals in order to identify background noise (i.e. noise other than voices or other desirable sound) and then adaptively filtering out the common background noises from each of the audio signals. Alternatively, the software embodiments include a method of pre-analyzing multiple incoming audio signals in order to identify a single common desirable sound (i.e. voices) and then adaptively enhancing the desirable sound within each of the multiple sources. | 03-19-2009 |
| 20090116662 | AUDIO PROCESSING METHOD AND SYSTEM - An audio processing method used in a microphone is provided. Firstly, a sound signal is received. Next, the sound signal is transduced to a first voltage signal. The first voltage signal is interfered with by a second voltage signal resulting from electromagnetic wave penetrating into the microphone. Next, the second voltage signal is filtered out from the interfered first voltage signal. Finally, the filtered first voltage signal is amplified. | 05-07-2009 |
| 20090175466 | NOISE-REDUCING DIRECTIONAL MICROPHONE ARRAY - In one embodiment, a directional microphone array having (at least) two microphones generates forward and backward cardioid signals from two (e.g., omnidirectional) microphone signals. An adaptation factor is applied to the backward cardioid signal, and the resulting adjusted backward cardioid signal is subtracted from the forward cardioid signal to generate a (first-order) output audio signal corresponding to a beampattern having no nulls for negative values of the adaptation factor. After low-pass filtering, spatial noise suppression can be applied to the output audio signal. Microphone arrays having one (or more) additional microphones can be designed to generate second- (or higher-) order output audio signals. | 07-09-2009 |
| 20090196434 | METHOD, APPARATUS, AND COMPUTER PROGRAM FOR SUPPRESSING NOISE - A method, an apparatus, and a computer program, which can suppress a low frequency range component with a small amount of calculation, and can achieve a noise suppression of high quality, are provided. The noise superposed in a desired signal of an input signal is suppressed by converting the input signal to a frequency domain signal; correcting an amplitude of the frequency domain signal to obtain an amplitude corrected signal; obtaining an estimated noise by using the amplitude corrected signal; determining a suppression coefficient by using the estimated noise and the amplitude corrected signal; and weighting the amplitude corrected signal with the suppression coefficient. | 08-06-2009 |
| 20090296958 | NOISE SUPPRESSION METHOD, DEVICE, AND PROGRAM - It is possible to provide a noise suppression method, device, and program capable of realizing a sound image positioning of an output side corresponding to an input side with a small calculation amount. The device includes a common suppression coefficient calculation unit for receiving conversion outputs from a plurality of channels and calculating a suppression coefficient common to the channels. | 12-03-2009 |
| 20100008520 | Noise Suppression Estimation Device and Noise Suppression Device - A noise suppression estimation device calculates a noise index value which varies according to kurtosis of a frequence distribution of magnitude of a sound signal before or after suppression of the noise component, the noise index value indicating a degree of occurrence of musical noise after suppression of the noise component in a frequency domain. For example, the noise suppression estimation device calculates first kurtosis of a frequence distribution of magnitude of the sound signal before suppression of the noise component, calculates second kurtosis of a frequence distribution of magnitude of the sound signal after suppression of the noise component, and calculates the noise index value from the first kurtosis and the second kurtosis. | 01-14-2010 |
| 20100104113 | NOISE SUPPRESSION DEVICE AND NOISE SUPPRESSION METHOD - In a noise suppression device, an audio detector detects presence or absence of audio in an input signal. A first noise spectrum estimator estimates a noise spectrum contained in the input signal based on the input signal and detection result of the audio detector. A second noise spectrum estimator estimates the noise spectrum based on the input signal regardless of the detection result of the audio detector. A noise spectrum calculator calculates a final noise spectrum estimation value according to a length of detecting time during which the audio detector continuously detects the audio and based on first and second noise spectrum estimation values that are obtained as estimation results by the first and second noise spectrum estimators. A gain calculator calculates a noise suppression gain based on the final noise spectrum estimation value. A noise suppressor suppresses noise contained in the input signal by applying the noise suppression gain to the input signal. | 04-29-2010 |
| 20100158269 | Method and apparatus for reducing wind noise - Techniques pertaining to techniques to reduce wind noises effectively in recorded signals are disclosed. According to one aspect of the present invention, there is a strong correlation between two voice signals from target voices in the same frequency band sampled simultaneously by a pair of microphones in a common scene while there is a weak correlation between wind noises in the same frequency band of the two voice signals sampled simultaneously by the pair of microphones in the common scene. Taking advantage of this feature to provide a larger gain to the frequency band having a strong correlation and a smaller gain to the frequency band having a weak correlation, thereby the wind noise is reduced efficiently with minimum impact on the target voices. | 06-24-2010 |
| 20100215190 | NOISE SUPPRESSING DEVICE, NOISE SUPPRESSING METHOD, AND RECORDING MEDIUM - A noise suppressing device includes a plurality of sound input units inputting sounds from a given sound source and converting the sounds to sound signals on a time axis, a transfer characteristic obtaining unit performing frequency transform of the sound signals after dividing the sound signals into frames and calculating respective transfer characteristics of the sounds for each given frequency band, a storage unit storing the calculated transfer characteristics of the sounds, a frequency obtaining unit obtaining a frequency for updating the transfer characteristics stored in the storage unit for the frequency band, an updating unit updating the transfer characteristics every given number of frames corresponding to the obtained frequency based on the transfer characteristics for each frequency band, a generating unit generating suppression information for suppressing the noise component based on the updated transfer characteristics, and a suppression unit suppressing the noise component based on the suppression information. | 08-26-2010 |
| 20100215191 | SOUND DETERMINATION DEVICE, SOUND DETECTION DEVICE, AND SOUND DETERMINATION METHOD - A noise removal device includes: an FFT analysis unit which receives a mixed sound including to-be-extracted sounds and noises, and determines frequency signals at time points in a time width; and a to-be-extracted sound determination unit which determines, for each to-be-extracted sound, frequency signals at the time points, satisfying conditions of (i) being equal to or greater than a first threshold value in number and (ii) having a phase distance between the frequency signals that is equal to or smaller than a second threshold value, wherein the phase distance is a distance between phases ψ′(t) of the condition-satisfying frequency signals when a phase of a frequency signal at a current time point t is ψ(t) (radian) and the phase ψ′(t) is mod 2π(ψ(t)−2πft), f denoting a reference frequency, and the predetermined time width is within 2 to 4 times the time window widths of the window functions. | 08-26-2010 |
| 20100232622 | METHOD FOR COMPENSATING FOR AN INTERFERENCE SOUND IN A HEARING APPARATUS, HEARING APPARATUS, AND METHOD FOR ADJUSTING A HEARING APPARATUS - A novel system prevents surrounding sound to enter through a hearing apparatus, for instance through a ventilation opening, and reach an eardrum of the wearer in the form of interference sound. Contrary to auditory accessories designed especially to protect against noise, it is not possible for many hearing apparatus to compensate for such an interference sound by means of active noise cancellation. The hearing apparatuses do not have the special components needed. No compensation sound signal can therefore form with a correct phase. In accordance with the invention, a compensation sound is only generated for a relatively narrow spectral band. This spectral band is determined as a function of a hearing ability of the wearer of the hearing apparatus and/or as a function of a spectral distribution of the energy of the interference sound or a sound producing the interference sound. The improvement is particularly suited to compensating for an interference sound in a hearing device. | 09-16-2010 |
| 20100239104 | System for Attenuating Noise in an Input Signal - A noise attenuation system attenuates noise in an input signal. The system may estimate a power of the input signal, and determine a noise power value based on the input power estimate. The noise power value corresponds to an estimate of a noise power within the input signal. The system may determine an attenuation factor based on the noise power value, and attenuate the input signal by using the attenuation factor. | 09-23-2010 |
| 20100260352 | SYSTEM IDENTIFICATION DEVICE AND SYSTEM IDENTIFICATION METHOD - A system identifying device for identifying an unknown system interposed between first and second input terminals. The system identifying device preferably comprises adaptive and dependent filters which receive a signal supplied through a first input terminal, a dependent filter factor updating unit for updating the filter factor of the dependent filter according to the filter factor of the adaptive filter, a first subtracter for subtracting the output signal outputted from the adaptive filter from the signal supplied through a second input terminal, a first output error mean computing section for computing a first output error mean from the output signal outputted from the first subracter, a second subracter for subtracting the output signal outputted from the dependent filter from the signal supplied through the second input terminal, a second output error mean computing section for computing a second output error mean from the output signal outputted from the second subtracter, and a comparator for comparing the first and second output error means. The first output error mean computing section computes the first output error mean from the components which are the remainder of reduction of the components of at least part of the frequency band superposed on the frequency band of the observed noise applied to the second input terminal out of the frequence band of the output signal outputted from the first subracter. The second output error mean computing section computes the second output error mean from the components which are the remainder of reduction of the components of at least part of the frequency band superposed on the frequency band of the observed noise applied to the second input terminal out of the frequency band of the output signal outputted from the second subtracter. At least either update of the filter factor of the adaptive filter by the output signal outputted from the first subracter or of the filter factor of the dependent filter by the dependent filter factor updating unit is controlled depending on the result of the comparison by the comparator. | 10-14-2010 |
| 20100272288 | APPARATUS AND METHOD FOR REMOVING WHITE NOISE IN PORTABLE TERMINAL - A method and an apparatus for removing white noise in a portable terminal are provided. The method for removing the white noise in the portable terminal includes measuring a volume variation of a voice signal output from a power amplifier; detecting a frequency band including white noise using the measured volume variation; and removing signals of the detected frequency band in the voice signal before output to speaker. | 10-28-2010 |
| 20100278354 | VOICE RECORDING METHOD, DIGITAL PROCESSOR AND MICROPHONE ARRAY SYSTEM - A microphone array system and a method implemented therefore are provided. A first microphone having a first sensibility receives a sound source to generate a first signal. A second microphone is deposited at a distance from the first microphone, having a second sensibility for receiving the sound source to generate a second signal. A comparator subtracts the first signal and the second signal to generate a difference signal. An analyzer estimates an incident angle of the sound source to determine a compensation factor based on the first signal and the difference signal. A gain stage adjusts a gain of the difference signal based on the compensation factor to output an output signal. | 11-04-2010 |
| 20100322437 | SIGNAL PROCESSING APPARATUS AND SIGNAL PROCESSING METHOD - There is provided a signal processing apparatus, for suppressing a noise, which includes a first calculator to obtain a phase difference between two spectrum signals in a frequency domain transformed from sound signals received by at least two microphones to estimate a sound source by the phase difference, a second calculator to obtain a value representing a target signal likelihood and to determine a sound suppressing phase difference range at each frequency, in which a sound signal is suppressed, on the basis of the target signal likelihood, and a filter. The filter generate a synchronized spectrum signal by synchronizing each frequency component of one of the two spectrum signals to each frequency component of the other of the two spectrum signals for each frequency when the phase difference is within the sound suppressing phase difference range and to generate a filtered spectrum signal. | 12-23-2010 |
| 20110019837 | MULTI-LEVEL OUTPUT SIGNAL CONVERTER - The present invention discloses a multi-level output signal converter, which is connected to an audio amplifier. The audio amplifier comprises a comparing/measuring device, an encoder and an output unit. The multi-level output signal converter comprises a timing processing unit and a multi-level converter. The timing processing unit is connected to the comparing/measuring device and the encoder. The timing processing unit includes a plurality of flip-flops and a timing summing element. The flip-flop receives a first signal from the comparing/measuring device and outputs the first signal to the timing summing element. The encoder converts the first signal into a second signal. The multi-level converter is connected to the encoder and the output unit. The encoder transmits the second signal to the multi-level converter, and the multi-level converter thus outputs a third signal to the output unit. | 01-27-2011 |
| 20110064241 | Methods and Systems for Reducing an Effect of Ambient Noise Within an Auditory Prosthesis System - An exemplary method of reducing an effect of ambient noise within an auditory prosthesis system includes dividing an audio signal presented to an auditory prosthesis patient into a plurality of analysis channels each containing a frequency domain signal representative of a distinct frequency portion of the audio signal, determining a signal-to-noise ratio and a noise reduction gain parameter based on the signal-to-noise ratio for each of the frequency domain signals, applying noise reduction to the frequency domain signals in accordance with the determined noise reduction gain parameters to generate a noise reduced frequency domain signal corresponding to each of the analysis channels, and generating one or more stimulation parameters based on the noise reduced frequency domain signals and in accordance with at least one of a current steering stimulation strategy and an N-of-M stimulation strategy. Corresponding methods and systems are also disclosed. | 03-17-2011 |
| 20110064242 | Method and System for Interference Suppression Using Blind Source Separation - A method of interference suppression is provided that includes receiving a first audio signal from a first audio capture device and a second audio signal from a second audio capture device wherein the first audio signal includes a first combination of desired audio content and interference and the second audio signal includes a second combination of the desired audio content and the interference, performing blind source separation using the first audio signal and the second audio signal to generate an output interference signal and an output audio signal including the desired audio content with the interference suppressed, estimating interference remaining in the output audio signal using the output interference signal, and subtracting the estimated interference from the output audio signal to generate a final output audio signal with the interference further suppressed. | 03-17-2011 |
| 20110123043 | Micro-Electromechanical System Microphone - A capacitive micro-electromechanical system (MEMS) microphone includes a semiconductor substrate having an opening that extends through the substrate. The microphone has a membrane that extends across the opening and a back-plate that extends across the opening. The membrane is configured to generate a signal in response to sound. The back-plate is separated from the membrane by an insulator and the back-plate exhibits a spring constant. The microphone further includes a back-chamber that encloses the opening to form a pressure chamber with the membrane, and a tuning structure configured to set a resonance frequency of the back-plate to a value that is substantially the same as a value of a resonance frequency of the membrane. | 05-26-2011 |
| 20110123044 | Method and Apparatus for Suppressing Wind Noise - The invention includes a method, apparatus, and computer program to selectively suppress wind noise while preserving narrow-band signals in acoustic data. Sound from one or several microphones is digitized into binary data. A time-frequency transform is applied to the data to produce a series of spectra. The spectra are analyzed to detect the presence of wind noise and narrow band signals. Wind noise is selectively suppressed while preserving the narrow band signals. The narrow band signal is interpolated through the times and frequencies when it is masked by the wind noise. A time series is then synthesized from the signal spectral estimate that can be listened to. This invention overcomes prior art limitations that require more than one microphone and an independent measurement of wind speed. Its application results in good-quality speech from data severely degraded by wind noise. | 05-26-2011 |
| 20110123045 | NOISE SUPPRESSOR - A noise suppressor selects, for individual frequency components, maximums by comparing a plurality of noise suppressed spectra | 05-26-2011 |
| 20110170709 | SYSTEMS AND METHODS TO REDUCE IDLE CHANNEL CURRENT AND NOISE FLOOR IN A PWM AMPLIFIER - Systems and methods provided herein decrease an idle channel noise floor and reduce power during an idle channel input for low power audio devices that include a digital pulse width modulation (PWM) amplifier having a noise shaper. An audio data signal is monitored for an idle channel condition. The noise shaper performs quantization of the audio data signal and uses noise shaper filter coefficients to shape noise resulting from the quantization. Predetermined values for the noise shaper filter coefficients are used to shape the noise resulting from quantization while the idle channel condition is not being detected. The values of the noise shaper filter coefficients are reduced so that the values move toward zeros, and the reduced values of the noise shaper filter coefficients are used to attenuate noise resulting from quantization, while the idle channel condition is being detected. The noise shaper filter coefficients are returned to the predetermined values when the idle channel condition is no longer detected. Alternative embodiments are also provided. | 07-14-2011 |
| 20110194708 | ACTIVE NOISE REDUCTION SYSTEM - An active noise reduction system is provided for receiving an audio input signal and a noise interference signal and calculating an audio broadcasting signal according to a Feedback Filtered-X Least-Mean-Square (FFXLMS) algorithm, wherein the FFXLMS algorithm optimizes a (convergence factor) μ so as to decrease the numbers of divisions operated by the active noise reduction system and increase the operation speed of the active noise reduction system. | 08-11-2011 |
| 20110280415 | SOUND REPRODUCTION AND DETECTION - Apparatus for generating a first acoustic signal and simultaneously sensing a second acoustic signal. The apparatus comprises: an input ( | 11-17-2011 |
| 20110293109 | Hands-Free Unit with Noise Tolerant Audio Sensor - A hands-free unit comprises a noise tolerant audio sensor to generate a first audio signal based on detection of audible sounds and an external audio sensor to generate a second audio signal based on detection of the audible sounds. A tunable distortion reduction filter adds high frequency information to the first audio signal and reduces distortion. A control unit detects noise levels based on comparison of first and second audio signals; and selects one of the first and second audio signals based on the detected noise level. | 12-01-2011 |
| 20110311075 | SPECTRAL BAND SUBSTITUTION TO AVOID HOWLS AND SUB-OSCILLATION - A listening device for processing an input sound to an output sound, includes an input transducer for converting an input sound to an electric input signal, an output transducer for converting a processed electric output signal to an output sound, a forward path being defined between the input transducer and the output transducer and including a signal processing unit for processing an input signal in a number of frequency bands and an SBS unit for performing spectral band substitution from one frequency band to another and providing an SBS-processed output signal, and an LG-estimator unit for estimating loop gain in each frequency band thereby identifying plus-bands having an estimated loop gain according to a plus-criterion and minus-bands having an estimated loop gain according to a minus-criterion. Based on an input from the LG-estimator unit, the SBS unit is adapted for substituting spectral content in a receiver band of the input signal with spectral content from a donor band in such a way that spectral content of the donor band is copied and possibly scaled with a scaling function and inserted in the receiver band instead of its original spectral content, wherein the receiver band is a plus-band and the donor band is a minus-band. | 12-22-2011 |
| 20110317848 | Microphone Interference Detection Method and Apparatus - A method and apparatus for detecting microphone interference includes first and second built-in microphones producing first and second microphone signals. A first filter bank creates first high-frequency-band and first low-frequency-band signals from the first microphone signal. A second filter bank creates second high-frequency-band and second low-frequency-band signals from the second microphone signal. A first measurement calculator determines a high-frequency-band energy value from the first high-frequency-band signal and the second high-frequency-band signal when the first and second high-frequency-band signals' magnitudes exceeds predetermined thresholds. A second measurement calculator calculates a low-frequency-band energy value from the first low-frequency-band signal and the second low-frequency-band signal when the first and second low-frequency-band signals' magnitudes exceed predetermined thresholds. A logic control block, coupled to the first measurement calculator and the second measurement calculator, detects microphone interference and produces an output signal indicating microphone occlusion or wind noise. | 12-29-2011 |
| 20120020494 | SIGNAL-COMPONENT EXTRACTION APPARATUS AND SIGNAL-COMPONENT EXTRACTION METHOD - In signal-component extraction, an input signal is delayed to generate a delayed input signal. The input signal is adaptively filtered with filter coefficients, to generate a filtered signal. The filtered signal is subtracted from the delayed input signal to generate an error signal. A preset reference value is divided by an amplitude of the input signal to generate a gain value. The filter coefficients are derived based on a value obtained by multiplying the input signal and error signal by the gain value or a square of the gain value. | 01-26-2012 |
| 20120057721 | COMPONENT HAVING A MICROMECHANICAL MICROPHONE STRUCTURE, AND METHOD FOR OPERATING SUCH A MICROPHONE COMPONENT - A concept is proposed for a MEMS microphone which may be operated at a relatively low voltage level and still have comparatively high sensitivity. The component according to the present invention includes a micromechanical microphone structure having an acoustically active diaphragm which functions as a deflectable electrode of a microphone capacitor ( | 03-08-2012 |
| 20120057722 | NOISE REMOVING APPARATUS AND NOISE REMOVING METHOD - Disclosed herein is a noise removing apparatus, including: an object sound emphasis section adapted to carry out an object sound emphasis process for observation signals of first and second microphones to produce an object sound estimation signal; a noise estimation section adapted to carry out a noise estimation process for the observation signals to produce a noise estimation signal; a post filtering section adapted to remove noise components remaining in the object sound estimation signal using the noise estimation signal; a correction coefficient calculation section adapted to calculate, for each frequency, a correction coefficient for correcting the post filtering process based on the object sound estimation signal and the noise estimation signal; and a correction coefficient changing section adapted to change those of the correction coefficients which belong to a frequency band suffering from spatial aliasing such that a peak appearing at a particular frequency is suppressed. | 03-08-2012 |
| 20120250885 | SIGNAL-PROCESSING DEVICE, IMAGING APPARATUS, AND SIGNAL-PROCESSING PROGRAM - A signal-processing device includes a determination section that compares a frequency spectrum and a floor spectrum of an input audio signal to each other for each frequency bin and determines whether the input audio signal should be subjected to noise reduction processing or not for each of the frequency bins; and a noise reduction-processing section that subtracts a noise frequency spectrum from the frequency spectrum of the input audio signal for each of the frequency bins on the basis of the result determined by the determination section for each of the frequency bins. | 10-04-2012 |
| 20120281856 | METHOD, SYSTEM AND ITEM - A method of enabling a hearer to hear desired sound while also being able to be aware of ambient sound, comprises providing a first non-audio signal representative of said desired sound, deriving a second non-audio signal from said ambient sound, combining the first and second non-audio signals in providing a third non-audio signal, and converting said third non-audio signal into sound. | 11-08-2012 |
| 20120288116 | WIND NOISE SUPPRESSOR, SEMICONDUCTOR INTEGRATED CIRCUIT, AND WIND NOISE SUPPRESSION METHOD - In a wind noise suppressor, a divider divides the frequency band an input sound into a first frequency band having a possibility that wind noise is included and a second frequency band having a frequency higher than a frequency of the first frequency band, a calculator calculates a probability that the input sound includes wind noise from feature parameters of a sound in the first frequency band, a suppressor suppresses wind noise included in the first frequency band in accordance with an intensity calculated from the probability, and an adder mixes and outputs the sound in the second frequency band divided by the divider and the sound in the first frequency band by which wind noise is suppressed by the suppressor. | 11-15-2012 |
| 20120288117 | NOISE FILLING AND AUDIO DECODING - A noise filling method is provided that includes detecting a frequency band including a part encoded to 0 from a spectrum obtained by decoding a bitstream; generating a noise component for the detected frequency band; and adjusting energy of the frequency band in which the noise component is generated and filled by using energy of the noise component and energy of the frequency band including the part encoded to 0. | 11-15-2012 |
| 20130010982 | NOISE-REDUCING DIRECTIONAL MICROPHONE ARRAY - In one embodiment, a directional microphone array having (at least) two microphones generates forward and backward cardioid signals from two (e.g., omnidirectional) microphone signals. An adaptation factor is applied to the backward cardioid signal, and the resulting adjusted backward cardioid signal is subtracted from the forward cardioid signal to generate a (first-order) output audio signal corresponding to a beampattern having no nulls for negative values of the adaptation factor. After low-pass filtering, spatial noise suppression can be applied to the output audio signal. Microphone arrays having one (or more) additional microphones can be designed to generate second- (or higher-) order output audio signals. | 01-10-2013 |
| 20130121506 | Online Source Separation - Online source separation may include receiving a sound mixture that includes first audio data from a first source and second audio data from a second source. Online source separation may further include receiving pre-computed reference data corresponding to the first source. Online source separation may also include performing online separation of the second audio data from the first audio data based on the pre-computed reference data. | 05-16-2013 |
| 20130136275 | AUDIO DEVICE AND METHOD FOR ADDING WATERMARK DATA TO AUDIO SIGNALS - An audio device comprises a processor, an audio processing module, a high frequency noise generating circuit, a first switch control circuit, a second switch control circuit, a low pass filter circuit and an adder circuit. The audio device generates a watermark data, an original audio signal and a high frequency noise signal. The high frequency noise signal pass through a first switch control circuit and a second switch control circuit according to watermark data. A low pass filter circuit filters the high frequency noise signal received from the first switch control circuit to form a first add data. An adder circuit receives the first add data from the low pass filter circuit, receives the high frequency noise signal from the second switch control circuit as a second add data, and adds the first add data and the second add data to the original audio signal. | 05-30-2013 |
| 20130322649 | AUDIO PROCESSING APPARATUS, AUDIO PROCESSING METHOD, AND PROGRAM - Provided is an audio processing apparatus including a frequency domain conversion unit configured to convert an audio signal input from a microphone to a frequency domain for each of frames, and a gain adjustment unit configured to perform gain adjustment for each of bands on the audio signal converted to the frequency domain. The gain adjustment unit acquires an autocorrelation value of power of the audio signal between the frames for each of the bands, and sets an adjustment amount of the gain in accordance with the acquired autocorrelation value. | 12-05-2013 |
| 20130329909 | PSYCHOACOUSTIC ADAPTIVE NOTCH FILTERING - Improved systems and methods for psychoacoustic adaptive notch filtering are provided. By accounting for psychoacoustic properties of an audio signal as well as finer characteristics of noise which may be present in the audio signal (e.g., the shape of the spectral density of the noise), more effective strategies for dealing with undesirable components of the audio signal may be realized. | 12-12-2013 |
| 20140056440 | FILTERING FOR DETECTION OF LIMITED-DURATION DISTORTION - Processing a signal includes: receiving data that includes an input signal; filtering the input signal to generate a filtered signal, such that if the input signal includes at least one instance of a nonlinear distortion of a desired signal then the filtered signal includes a signature signal corresponding to the nonlinear distortion, the nonlinear distortion characterized by a time duration that is within a predetermined range; and detecting whether or not the filtered signal includes the signature signal. | 02-27-2014 |
| 20140153743 | AUDIO PROCESSING DEVICE AND METHOD - An audio processing device includes a setting section that sets a reproduction sampling frequency F | 06-05-2014 |
| 20140161278 | SOUND REPRODUCTION DEVICE - A sound reproduction device includes a modulator having an output terminal for outputting a modulated carrier wave signal obtained by modulating a carrier wave signal in a ultrasonic band with an audible sound signal, a super-directivity loudspeaker connected to the output terminal, a capacitor connected between a ultrasonic wave source and a ground, first and second current detectors for detecting currents flowing through the super-directivity loudspeaker and the capacitor, a high-pass filter for outputting a filtered signal obtained by eliminating a low-frequency band component of the current detected by the first current detector, and a differential amplifier unit for outputting a signal corresponding to a difference between the filtered signal and the current detected by the second current detector. The ultrasonic wave source is configured to output the carrier wave signal such that the signal output from the differential amplifier unit is constant. | 06-12-2014 |
| 20140185827 | NOISE SUPPRESSION APPARATUS AND CONTROL METHOD THEREOF - A noise suppression apparatus using spectral subtraction is provided. A noise estimation unit estimates noise components included in a mixed signal. A fundamental frequency of the mixed signal is detected. A subtraction factor in the spectral subtraction is set based on the detected fundamental frequency. The spectral subtraction for the mixed signal is executed using the set subtraction factor and the estimated noise components. A boundary frequency at the fundamental frequency or a frequency lower than the fundamental frequency is set, and a subtraction factor for a frequency lower than the boundary frequency is set to assume a value larger than a subtraction factor for a frequency not less than the boundary frequency. | 07-03-2014 |
| 20140211965 | AUDIO BANDWIDTH DEPENDENT NOISE SUPPRESSION - A system and method for audio bandwidth dependent noise suppression may detect the audio bandwidth of an audio signal responsive to one or more audio indicators. The audio indicators may include the audio sampling rate and characteristics of an associated compression format. Noise suppression gains may be calculated responsive to the audio signal. Noise suppression gains may mitigate undesirable noise in the reproduced output signal. The noise suppression gains may be modified responsive to the detected audio bandwidth. Less noise reduction may be desirable when more audio bandwidth is available. The modified noise suppression gains may be applied to the audio signal. | 07-31-2014 |
| 20140376742 | SOUND FIELD SPATIAL STABILIZER WITH SPECTRAL COHERENCE COMPENSATION - In a system and method for maintaining the spatial stability of a sound field a balance gain may be calculated for two or more microphone signals. The balance gain may be associated with a spatial image in the sound field. Signal values may be calculated for each of the microphone. The signal values may be signal estimates or signal gains calculated to improve a characteristic of the microphone signals. The differences between the signal values associated with each microphone signal may be limited although some difference between signal values may be allowable. One or more microphone signals are adjusted responsive to the two or more balance gains and the signal gains to maintain the spatial stability of the sound field. The adjustments of one or more microphone signals may include mixing of two or more microphone. The signal gains are applied to the two or more microphone signals. | 12-25-2014 |
| 20140376743 | SOUND FIELD SPATIAL STABILIZER WITH STRUCTURED NOISE COMPENSATION - In a system and method for maintaining the spatial stability of a sound field a balance gain may be calculated for two or more microphone signals. The balance gain may be associated with a spatial image in the sound field. Signal values may be calculated for each of the microphone. The signal values may be signal estimates or signal gains calculated to improve a characteristic of the microphone signals. The differences between the signal values associated with each microphone signal may be limited although some difference between signal values may be allowable. One or more microphone signals are adjusted responsive to the two or more balance gains and the signal gains to maintain the spatial stability of the sound field. The adjustments of one or more microphone signals may include mixing of two or more microphone. The signal gains are applied to the two or more microphone signals. | 12-25-2014 |
| 20140376744 | SOUND FIELD SPATIAL STABILIZER WITH ECHO SPECTRAL COHERENCE COMPENSATION - In a system and method for maintaining the spatial stability of a sound field a balance gain may be calculated for two or more microphone signals. The balance gain may be associated with a spatial image in the sound field. Signal values may be calculated for each of the microphone. The signal values may be signal estimates or signal gains calculated to improve a characteristic of the microphone signals. The differences between the signal values associated with each microphone signal may be limited although some difference between signal values may be allowable. One or more microphone signals are adjusted responsive to the two or more balance gains and the signal gains to maintain the spatial stability of the sound field. The adjustments of one or more microphone signals may include mixing of two or more microphone. The signal gains are applied to the two or more microphone signals. | 12-25-2014 |
| 20150030180 | POST-PROCESSING GAINS FOR SIGNAL ENHANCEMENT - A method, an apparatus, and logic to post-process raw gains determined by input processing to generate post-processed gains, comprising using one or both of delta gain smoothing and decision-directed gain smoothing. The delta gain smoothing comprises applying a smoothing filter to the raw gain with a smoothing factor that depends on the gain delta: the absolute value of the difference between the raw gain for the current frame and the post-processed gain for a previous frame. The decision-directed gain smoothing comprises converting the raw gain to a signal-to-noise ratio, applying a smoothing filter with a smoothing factor to the signal-to-noise ratio to calculate a smoothed signal-to-noise ratio, and converting the smoothed signal-to-noise ratio to determine the second smoothed gain, with smoothing factor possibly dependent on the gain delta. | 01-29-2015 |
| 20150055800 | ENHANCEMENT OF INTELLIGIBILITY IN NOISY ENVIRONMENT - Provided are methods and systems for enhancing the intelligibility of an audio (e.g., speech) signal rendered in a noisy environment, subject to a constraint on the power of the rendered signal. A quantitative measure of intelligibility is the mean probability of decoding of the message correctly. The methods and systems simplify the procedure by approximating the maximization of the decoding probability with the maximization of the similarity of the spectral dynamics of the noisy speech to the spectral dynamics of the corresponding noise-free speech. The intelligibility enhancement procedures provided are based on this principle, and all have low computational cost and require little delay, thus facilitating real-time implementation. | 02-26-2015 |
| 20150071462 | METHODS AND SYSTEM FOR WIDEBAND SIGNAL PROCESSING IN COMMUNICATION NETWORK - The embodiments herein disclose a device and a method for controlling noise in a wideband communication system. In one embodiment herein, multiple microphones for receiving wideband audio signals are provided. A processor is configured to analyze each wideband audio signal received by each microphone. Further, unique signal patterns are generated based on each analyzed wideband signals for each microphone and the unique signal patterns are compared to detect any identical signal patterns. A controller is also provided for controlling gains of those microphones that are detected to be receiving wideband audio signal of identical signal patterns. | 03-12-2015 |
| 20150139446 | AUDIO SIGNAL PROCESSING APPARATUS AND METHOD - An audio separating apparatus obtains a matrix by performing time-frequency conversion on an input audio signal. The audio separating apparatus divides the obtained matrix into at least a basis matrix and an activity matrix, and classifies base spectra that configure the respective columns of the basis matrix into first base spectra corresponding to a target sound and second base spectra corresponding to a non-target sound. | 05-21-2015 |
| 20150304775 | DISTORTION SOUND CORRECTION COMPLEMENT DEVICE AND DISTORTION SOUND CORRECTION COMPLEMENT METHOD - A device and method relates to reducing distortion of signal. The device includes a first filter unit for generating a correction band signal, a signal level detection unit for detecting a signal level of the correction band signal, a first lookup table unit for determining a control signal, a second lookup table unit for determining a correction amount, a correction band extraction signal generation unit for generating a correction band extraction signal, a correction signal generation unit for generating a correction signal, a first edge detection unit for generating an overtone signal from the correction band extraction signal, a filter unit for suppressing high-frequency range and low-frequency range signal levels of the overtone signal, a first amplification unit for amplifying the overtone signal, a second filter unit for generating a complement signal from the overtone signal, and an output signal generation unit for generating an output signal. | 10-22-2015 |
| 20150348568 | SYSTEM AND METHOD FOR DYNAMIC RESIDUAL NOISE SHAPING - A system and method for dynamic residual noise shaping configured to reduce hiss noise in an audio signal. The system and method may detect an amount and type of hiss noise. The system and method may limit calculated noise suppression gains responsive to the detected amount and type of hiss noise. The limited noise suppression gains may be applied to the audio signal and may reduce the hiss noise. | 12-03-2015 |
| 20160035334 | AUDIO SYSTEM AND METHOD FOR REDUCTION AND/OR ELIMINATION OF DISTORTION - An audio system for reduction and/or elimination of distortion provides a microphone or instrument sound pick up for the various musical instruments and singers within the performance venue. The sound provided by the microphone or audio pick up is coupled to an amplifier, the output of which is coupled to a speaker system. In accordance with the present invention, a microphone is positioned within the output range of the speaker system and is coupled to one input of a comparator circuit. The remaining input of the comparator circuit is coupled to the microphones or pick ups of the musical instruments and singers. An additive device receives the output signal of the comparator and the originating signal from the microphones or pick ups to form a correcting audio signal which is applied to the amplifier. In an alternate embodiment of the present invention, an adaptive preamplifier is interposed between the originating microphones and audio pick ups and the amplifier. The adaptive preamplifier receives the output of the comparator and imposes alteration upon the signal processed through the preamplifier for application to the amplifier. In a still further alternate embodiment of the present invention, an adaptive amplifier includes a plurality of control elements which are capable of altering the transmission characteristic of the amplifier for the applied signals. The adaptive controls are coupled to and controlled by the comparator. | 02-04-2016 |
| 20160035337 | ENHANCING AUDIO USING A MOBILE DEVICE - Embodiments disclosed herein enable detection and improvement of the quality of the audio signal using a mobile device by determining the loss in the audio signal and enhancing audio by streaming the remainder portion of audio. Embodiments disclosed herein enable an improvement in the sound quality rendered by rendering devices by emitting an test audio signal from the source device, measuring the test audio signal using microphones, detecting variation in the frequency response, loudness and timing characteristics using impulse responses and correcting for them. Embodiments disclosed herein also compensate for the noise in the acoustic space by determining the reverberation and ambient noise levels and their frequency characteristics and changing the digital filters and volumes of the source signal to compensate for the varying noise levels. | 02-04-2016 |
| 20160066089 | SYSTEM AND METHOD FOR ADAPTIVE INTELLIGENT NOISE SUPPRESSION - Systems and methods for adaptive intelligent noise suppression are provided. In exemplary embodiments, a speech distortion estimate is determined based on a primary acoustic signal which represents at least one captured sound. The speech distortion estimate is used to derive control signals which adjust an enhancement filter. The enhancement filter is used to generate a plurality of gain masks, which may be applied to the primary acoustic signal to generate a noise suppressed signal. | 03-03-2016 |
| 20160078856 | APPARATUS AND METHOD FOR ELIMINATING NOISE, SOUND RECOGNITION APPARATUS USING THE APPARATUS AND VEHICLE EQUIPPED WITH THE SOUND RECOGNITION APPARATUS - An apparatus for eliminating noise includes: a gain acquisition unit that determines a gain and a correction value of the gain using a signal to noise ratio (SNR) of an input signal; and a gain application unit that acquires an output signal corresponding to the input signal using the determined gain and the determined correction value, wherein the output signal includes an input signal of which noise is eliminated and an input signal of which noise is not eliminated, and a proportion of the input signal of which noise is eliminated and a proportion of the input signal of which noise is not eliminated are determined according to the determined correction value. | 03-17-2016 |
| 20160118057 | SELECTIVE BASS POST FILTER - In some embodiments, a pitch filter for filtering a preliminary audio signal generated from an audio bitstream is disclosed. The pitch filter has an operating mode selected from one of either: (i) an active mode where the preliminary audio signal is filtered using filtering information to obtain a filtered audio signal, and (ii) an inactive mode where the pitch filter is disabled. The preliminary audio signal is generated in an audio encoder or audio decoder having a coding mode selected from at least two distinct coding modes, and the pitch filter is capable of being selectively operated in either the active mode or the inactive mode while operating in the coding mode based on control information. | 04-28-2016 |
| 20160133271 | Microphone With Electronic Noise Filter - An acoustic apparatus includes a microelectromechanical system (MEMS) device, a controlled filter coupled to the MEMS device, and an amplifier. The controllable filter and the amplifier are coupled together at a node. A cut-off frequency of the filter is selectable based upon reception or non-reception of a low frequency audio signal by the acoustic apparatus. | 05-12-2016 |
| 20160157037 | ACOUSTIC FEEDBACK CANCELLER | 06-02-2016 |
| 20160180859 | AUDIO SIGNAL PROCESSING CIRCUIT | 06-23-2016 |
| 20160254008 | SIGNAL PROCESSING APPARATUS, MEDIUM APPARATUS, SIGNAL PROCESSING METHOD, AND SIGNAL PROCESSING PROGRAM | 09-01-2016 |
| 20160379663 | Noise Detection Device, Noise Detection Method, and Noise Detection Program - A frame signal generator is configured to generate a frame signal with a predetermined first time length from an input signal. A reference signal generator is configured to generate a reference signal from a signal located more in a past than a position of the frame signal in the input signal. A correlation value calculator is configured to calculate a correlation value between the frame signal and the reference signal within a range of a predetermined phase shift amount m. A periodic noise determiner is configured to determine whether or not the frame signal includes periodic noise, and calculate a period of the periodic noise in the case where the frame signal includes the periodic noise. A correlation value calculation range generator is configured to generate the range of the predetermined phase shift amount based on the period of the periodic noise. | 12-29-2016 |
