Patent application number | Description | Published |
20090110209 | SYSTEM FOR COMFORT NOISE INJECTION - A noise injection system adds comfort noise to an audio signal. The system includes a background noise estimator that determines a spectral content of a background noise associated with the audio signal. A comfort noise generator generates a comfort noise signal having a random phase. A gain circuit adjusts the comfort noise signal based on the spectral content of the background noise. A combining circuit combines a gain-adjusted comfort noise signal and the audio signal to generate an output signal. | 04-30-2009 |
20090112579 | SPEECH ENHANCEMENT THROUGH PARTIAL SPEECH RECONSTRUCTION - A system improves speech intelligibility by reconstructing speech segments. The system includes a low-frequency reconstruction controller programmed to select a predetermined portion of a time domain signal. The low-frequency reconstruction controller substantially blocks signals above and below the selected predetermined portion. A harmonic generator generates low-frequency harmonics in the time domain that lie within a frequency range controlled by a background noise modeler. A gain controller adjusts the low-frequency harmonics to substantially match the signal strength to the time domain original input signal. | 04-30-2009 |
20090112584 | DYNAMIC NOISE REDUCTION - A speech enhancement system improves the speech quality and intelligibility of a speech signal. The system includes a time-to-frequency converter that converts segments of a speech signal into frequency bands. A signal detector measures the signal power of the frequency bands of each speech segment. A background noise estimator measures a background noise detected in the speech signal. A dynamic noise reduction controller dynamically models the background noise in the speech signal. The speech enhancement renders a speech signal perceptually pleasing to a listener by dynamically attenuating a portion of the noise that occurs in a portion of the spectrum of the speech signal. | 04-30-2009 |
20090222268 | SPEECH SYNTHESIS SYSTEM HAVING ARTIFICIAL EXCITATION SIGNAL - A speech synthesis system synthesizes a speech signal corresponding to an input speech signal based on a spectral envelope of the input speech signal. A glottal pulse generator generates a time series of glottal pulses, that are processed into a glottal pulse magnitude spectrum. A shaping circuit shapes the glottal pulse magnitude spectrum based on the spectral envelope and generates a shaped glottal pulse magnitude spectrum. A harmonic null adjustment circuit reduces harmonic nulls in the shaped glottal pulse magnitude spectrum and generates a null-adjusted synthesized speech spectrum. An inverse transform circuit generates a null-adjusted time-series speech signal. An overlap and add circuit synthesizes the speech signal based on the null-adjusted time-series speech signal. | 09-03-2009 |
20090287481 | SPEECH ENHANCEMENT SYSTEM - A speech enhancement system improves speech conversion within an encoder and decoder. The system includes a first device that converts sound waves into operational signals. A second device selects a template that represents an expected signal model. The selected template models speech characteristics of the operational signals through a speech codebook that is further accessed in a communication channel. | 11-19-2009 |
20090292536 | Speech enhancement with minimum gating - A speech enhancement system enhances transitions between speech and non-speech segments. The system includes a background noise estimator that approximates the magnitude of a background noise of an input signal that includes a speech and a non-speech segment. A slave processor is programmed to perform the specialized task of modifying a spectral tilt of the input signal to match a plurality of expected spectral shapes selected by a Codec. | 11-26-2009 |
20110026734 | System for Suppressing Wind Noise - A voice enhancement logic improves the perceptual quality of a processed voice. The voice enhancement system includes a noise detector and a noise attenuator. The noise detector detects a wind buffet and a continuous noise by modeling the wind buffet. The noise attenuator dampens the wind buffet to improve the intelligibility of an unvoiced, a fully voiced, or a mixed voice segment. | 02-03-2011 |
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 |
20120035921 | Dynamic Noise Reduction - A speech enhancement system improves the speech quality and intelligibility of a speech signal. The system includes a time-to-frequency converter that converts segments of a speech signal into frequency bands. A signal detector measures the signal power of the frequency bands of each speech segment. A background noise estimator measures a background noise detected in the speech signal. A dynamic noise reduction controller dynamically models the background noise in the speech signal. The speech enhancement renders a speech signal perceptually pleasing to a listener by dynamically attenuating a portion of the noise that occurs in a portion of the spectrum of the speech signal. | 02-09-2012 |
20120173231 | SYSTEM FOR COMFORT NOISE INJECTION - A noise injection system adds comfort noise to an audio signal. The system includes a background noise estimator that determines a spectral content of a background noise associated with the audio signal. A comfort noise generator generates a comfort noise signal having a random phase. A gain circuit adjusts the comfort noise signal based on the spectral content of the background noise. A combining circuit combines a gain-adjusted comfort noise signal and the audio signal to generate an output signal. | 07-05-2012 |
20130073284 | Speech Enhancement System - A speech enhancement system improves speech conversion within an encoder and decoder. The system includes a first device that converts sound waves into operational signals. A second device selects a template that represents an expected signal model. The selected template models speech characteristics of the operational signals through a speech codebook that is further accessed in a communication channel. | 03-21-2013 |
20130080158 | Speech Enhancement with Minimum Gating - A speech enhancement system enhances transitions between speech and non-speech segments. The system includes a background noise estimator that approximates the magnitude of a background noise of an input signal that includes a speech and a non-speech segment. A slave processor is programmed to perform the specialized task of modifying a spectral tilt of the input signal to match a plurality of expected spectral shapes selected by a Codec. | 03-28-2013 |
20130223645 | 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. | 08-29-2013 |
20130297306 | Adaptive Equalization System - An adaptive equalization system that adjusts the spectral shape of a speech signal based on an intelligibility measurement of the speech signal may improve the intelligibility of the output speech signal. Such an adaptive equalization system may include a speech intelligibility measurement module, a spectral shape adjustment module, and an adaptive equalization module. The speech intelligibility measurement module is configured to calculate a speech intelligibility measurement of a speech signal. The spectral shape adjustment module is configured to generate a weighted long-term speech curve based on a first predetermined long-term average speech curve, a second predetermined long-term average speech curve, and the speech intelligibility measurement. The adaptive equalization module is configured to adapt equalization coefficients for the speech signal based on the weighted long-term speech curve. | 11-07-2013 |
20140365211 | ADAPTIVE EQUALIZATION SYSTEM - An adaptive equalization system that adjusts the spectral shape of a speech signal based on an intelligibility measurement of the speech signal may improve the intelligibility of the output speech signal. Such an adaptive equalization system may include a speech intelligibility measurement module, a spectral shape adjustment module, and an adaptive equalization module. The speech intelligibility measurement module is configured to calculate a speech intelligibility measurement of a speech signal. The spectral shape adjustment module is configured to generate a weighted long-term speech curve based on a first predetermined long-term average speech curve, a second predetermined long-term average speech curve, and the speech intelligibility measurement. The adaptive equalization module is configured to adapt equalization coefficients for the speech signal based on the weighted long-term speech curve. | 12-11-2014 |