Patent application number | Description | Published |
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 |
20090198356 | Primary-Ambient Decomposition of Stereo Audio Signals Using a Complex Similarity Index - An audio signal is processed to derive primary and ambient components of the signal. The signal is first transformed to generate frequency-domain subband signals. Primary and ambient components are separated by comparing frequency subband content using a complex-valued similarity metric, wherein one of the primary and ambient components is determined to be the residual after the other is identified using the similarity metric. | 08-06-2009 |
20090220107 | System and method for providing single microphone noise suppression fallback - Systems and methods for providing single microphone noise suppression fallback are provided. In exemplary embodiments, primary and secondary acoustic signals are received. A single microphone noise estimate may be generated based on the primary acoustic signal, while a dual microphone noise estimate may be generated based on the primary and secondary acoustic signals. A combined noise estimate based on the single and dual microphone noise estimates is then determined. Using the combined noise estimate, a gain mask may be generated and applied to the primary acoustic signal to generate a noise suppressed signal. Subsequently, the noise suppressed signal may be output. | 09-03-2009 |
20100094643 | Systems and methods for reconstructing decomposed audio signals - Systems and methods for reconstructing decomposed audio signals are presented. In exemplary embodiments, a decomposed audio signal is received. The decomposed audio signal may include a plurality of frequency sub-band signals having successively shifted group delays as a function of frequency from a filter bank. The plurality of frequency sub-band signals may then be grouped into two or more groups. A delay function may be applied to at least one of the two or more groups. Subsequently, the groups may be combined to reconstruct the audio signal, which may be outputted accordingly. | 04-15-2010 |
20110129095 | Audio Zoom - An audio equivalent of a video zoom feature for video recording and communication applications, as well as video post production processes. The audio zoom may operate in conjunction with a video zoom feature or independently. The audio zoom may be achieved by controlling reverberation effects of a signal, controlling a gain of the signal, as well as controlling the width of a directional beam from which is used to select the particular audio component to focus on. The audio zoom may operate in response to user input, such as a user selection of a particular direction, or automatically based a current environment or other factors. | 06-02-2011 |
20110257967 | Method for Jointly Optimizing Noise Reduction and Voice Quality in a Mono or Multi-Microphone System - The present technology provides adaptive noise reduction of an acoustic signal using a sophisticated level of control to balance the tradeoff between speech loss distortion and noise reduction. The energy level of a noise component in a sub-band signal of the acoustic signal is reduced based on an estimated signal-to-noise ratio of the sub-band signal, and further on an estimated threshold level of speech distortion in the sub-band signal. In embodiments, the energy level of the noise component in the sub-band signal may be reduced to no less than a residual noise target level. Such a target level may be defined as a level at which the noise component ceases to be perceptible. | 10-20-2011 |
20120010881 | Monaural Noise Suppression Based on Computational Auditory Scene Analysis - The present technology provides a robust noise suppression system which may concurrently reduce noise and echo components in an acoustic signal while limiting the level of speech distortion. An acoustic signal may be received and transformed to cochlear domain sub-band signals. Features such as pitch may be identified and tracked within the sub-band signals. Initial speech and noise models may be then be estimated at least in part from a probability analysis based on the tracked pitch sources. Speech and noise models may be resolved from the initial speech and noise models and noise reduction may be performed on the sub-band signals and an acoustic signal may be reconstructed from the noise-reduced sub-band signals. | 01-12-2012 |
20120027218 | Multi-Microphone Robust Noise Suppression - A robust noise reduction system may concurrently reduce noise and echo components in an acoustic signal while limiting the level of speech distortion. The system may receive acoustic signals from two or more microphones in a close-talk, hand-held or other configuration. The received acoustic signals are transformed to cochlea domain sub-band signals and echo and noise components may be subtracted from the sub-band signals. Features in the acoustic sub-band signals are identified and used to generate a multiplicative mask. The multiplicative mask is applied to the noise subtracted sub-band signals and the sub-band signals are reconstructed in the time domain. | 02-02-2012 |
20120179461 | METHOD FOR JOINTLY OPTIMIZING NOISE REDUCTION AND VOICE QUALITY IN A MONO OR MULTI-MICROPHONE SYSTEM - The present technology provides adaptive noise reduction of an acoustic signal using a sophisticated level of control to balance the tradeoff between speech loss distortion and noise reduction. The energy level of a noise component in a sub-band signal of the acoustic signal is reduced based on an estimated signal-to-noise ratio of the sub-band signal, and further on an estimated threshold level of speech distortion in the sub-band signal. In embodiments, the energy level of the noise component in the sub-band signal may be reduced to no less than a residual noise target level. Such a target level may be defined as a level at which the noise component ceases to be perceptible. | 07-12-2012 |
20130096914 | System And Method For Utilizing Inter-Microphone Level Differences For Speech Enhancement - Systems and methods for utilizing inter-microphone level differences to attenuate noise and enhance speech are provided. In exemplary embodiments, energy estimates of acoustic signals received by a primary microphone and a secondary microphone are determined in order to determine an inter-microphone level difference (ILD). This ILD in combination with a noise estimate based only on a primary microphone acoustic signal allow a filter estimate to be derived. In some embodiments, the derived filter estimate may be smoothed. The filter estimate is then applied to the acoustic signal from the primary microphone to generate a speech estimate. | 04-18-2013 |
20130231925 | Monaural Noise Suppression Based on Computational Auditory Scene Analysis - The present technology provides a robust noise suppression system that may concurrently reduce noise and echo components in an acoustic signal while limiting the level of speech distortion. A time-domain acoustic signal may be received and be transformed to frequency-domain sub-band signals. Features, such as pitch, may be identified and tracked within the sub-band signals. Initial speech and noise models may be then be estimated at least in part from a probability analysis based on the tracked pitch sources. Speech and noise models may be resolved from the initial speech and noise models and noise reduction may be performed on the sub-band signals. An acoustic signal may be reconstructed from the noise-reduced sub-band signals. | 09-05-2013 |
20130251170 | Jointly Optimizing Noise Reduction and Voice Quality in a Mono or Multi-Microphone System - The present technology provides adaptive noise reduction of an acoustic signal using a sophisticated level of control to balance the tradeoff between speech loss distortion and noise reduction. The energy level of a noise component in a sub-band signal of the acoustic signal is reduced based on an estimated signal-to-noise ratio of the sub-band signal, and further on an estimated threshold level of speech distortion in the sub-band signal. In various embodiments, the energy level of the noise component in the sub-band signal may be reduced to no less than a residual noise target level. Such a target level may be defined as a level at which the noise component ceases to be perceptible. | 09-26-2013 |
20130322643 | Multi-Microphone Robust Noise Suppression - A robust noise reduction system may concurrently reduce noise and echo components in an acoustic signal while limiting the level of speech distortion. The system may receive acoustic signals from two or more microphones in a close-talk, hand-held or other configuration. The received acoustic signals are transformed to frequency domain sub-band signals and echo and noise components may be subtracted from the sub-band signals. Features in the acoustic sub-band signals are identified and used to generate a multiplicative mask. The multiplicative mask is applied to the noise subtracted sub-band signals and the sub-band signals are reconstructed in the time domain. | 12-05-2013 |
20130332171 | Bandwidth Extension via Constrained Synthesis - Audio signal bandwidth extension may be performed on a narrow bandwidth signal received from a remote source over the audio communication network. The narrow band signal bandwidth may be extended such that the bandwidth is greater than that of the audio communication network. The signal may be extended by synthesizing an audio signal having spectral values within an extended bandwidth from synthetic components. The synthetic components may be generated using parameters derived from original narrowband audio signal. The audio signal may be synthesized in the form of an excitation signal and vocal tract envelope. The excitation signal and vocal tract may be extended independently. In various embodiments, excitation components may be derived from constrained synthesis using a constraint filter with nulls in regions where the extension is desired. | 12-12-2013 |
20140205107 | ADAPTIVE NOISE REDUCTION USING LEVEL CUES - A system utilizing two pairs of microphones for noise suppression. Primary and secondary microphones may be positioned closely spaced to each other to provide acoustic signals used to achieve noise cancellation/suppression. An additional, tertiary microphone may be spaced with respect to either the primary microphone or the secondary microphone in a spread-microphone configuration for deriving level cues from audio signals provided by the tertiary and the primary or secondary microphone. The level cues are expressed via a level difference used to determine one or more cluster tracking control signal(s). The level difference-based cluster tracking signals are used to control adaptation of noise suppression. A noise cancelled primary acoustic signal and level difference-based cluster tracking control signals are used during post filtering to adaptively generate a mask to be applied to a speech estimate signal. | 07-24-2014 |
Patent application number | Description | Published |
20100089081 | VENDING MACHINE AND METHOD FOR DEFROSTING - A method includes sensing an exposure of a refrigerated compartment of a vending machine to ambient air and, in response, sensing an initial temperature of the refrigerated compartment. The method also includes, responsive to sensing the exposure to ambient air, selecting a procedure from a plurality of procedures according to the sensed initial temperature, and controlling a refrigeration system of the vending machine using the selected procedure during an initial period. The method may include sensing a current temperature of the vending machine and, once the refrigerated compartment reaches a second predetermined temperature, controlling the refrigeration system according to the sensed current temperature, monitoring an operational characteristic of a compressor of the refrigeration system, and performing a defrost procedure according to the monitored operational characteristic. | 04-15-2010 |
20100133290 | REFRIGERATION DECK SYSTEM FOR VENDING MACHINE - A vending machine includes a product compartment, a duct opening into the product compartment, and a self-contained refrigeration system. The refrigeration system includes a housing having a first chamber and a second chamber. The first chamber includes first and second openings. The second chamber includes third and fourth openings. An evaporator coil and evaporator fan are mounted in the first chamber. The evaporator fan moves air from the first opening, through the evaporator coil, to the second opening. A condensing coil, compressor, and compressor fan are mounted in the second chamber. The compressor fan moves air from the third opening, through the condensing coil, over the compressor, to the fourth opening. The housing thermally insulates the first chamber from both the second chamber and an exterior of the housing. The housing also seals the first chamber, such that substantially all air in the first chamber enters the first chamber through the first opening and exits the first chamber through the second opening. The housing is further adapted to automatically couple the first opening to the product storage compartment and the second opening to the duct when the housing is inserted into the vending machine. | 06-03-2010 |