Patents by Inventor Wai C. Chu

Wai C. Chu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 10966022
    Abstract: An augmented reality environment allows interaction between virtual and real objects. Multiple microphone arrays of different physical sizes are used to acquire signals for spatial tracking of one or more sound sources within the environment. A first array with a larger size may be used to track an object beyond a threshold distance, while a second array having a size smaller than the first may be used to track the object up to the threshold distance. By selecting different sized arrays, accuracy of the spatial location is improved.
    Type: Grant
    Filed: June 25, 2018
    Date of Patent: March 30, 2021
    Assignee: Amazon Technologies, Inc.
    Inventors: Wai C. Chu, Edward Dietz Crump
  • Patent number: 10242695
    Abstract: Techniques for enhancing an acoustic echo canceller based on visual cues are described herein. The techniques include changing adaptation of a filter of the acoustic echo canceller, calibrating the filter, or reducing background noise from an audio signal processed by the acoustic echo canceller. The changing, calibrating, and reducing are responsive to visual cues that describe acoustic characteristics of a location of a device that includes the acoustic echo canceller. Such visual cues may indicate that no human being is present at the location, that some subject(s) are engaged in speaking or sound generating activities, or that motion associated with an echo path change has occurred at the location.
    Type: Grant
    Filed: September 14, 2017
    Date of Patent: March 26, 2019
    Assignee: Amazon Technologies, Inc.
    Inventors: Kavitha Velusamy, Wai C. Chu, Ramya Gopalan, Amit S. Chhetri
  • Patent number: 9767828
    Abstract: Techniques for enhancing an acoustic echo canceller based on visual cues are described herein. The techniques include changing adaptation of a filter of the acoustic echo canceller, calibrating the filter, or reducing background noise from an audio signal processed by the acoustic echo canceller. The changing, calibrating, and reducing are responsive to visual cues that describe acoustic characteristics of a location of a device that includes the acoustic echo canceller. Such visual cues may indicate that no human being is present at the location, that some subject(s) are engaged in speaking or sound generating activities, or that motion associated with an echo path change has occurred at the location.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: September 19, 2017
    Assignee: Amazon Technologies, Inc.
    Inventors: Kavitha Velusamy, Wai C. Chu, Ramya Gopalan, Amit S. Chhetri
  • Patent number: 9560446
    Abstract: A sound source locator efficiently employs a distributed physical or logical microphone array to determine a location of a source of a sound. In some instances, the sound source locator is deployed in an augmented reality environment. The sound source locator detects sound at a plurality of microphones, generates a signal corresponding to the sound, and causes attributes of signal as generated at the plurality of microphones to be stored in association with the corresponding microphone. The sound source locator uses these stored attributes to identify multiple groups of the plurality of microphones from which delays between the times the signal is generated can be used to compute the location of the source of the sound.
    Type: Grant
    Filed: June 27, 2012
    Date of Patent: January 31, 2017
    Assignee: Amazon Technologies, Inc.
    Inventors: Samuel Henry Chang, Wai C. Chu
  • Patent number: 9489948
    Abstract: An augmented reality environment allows interaction between virtual and real objects. Multiple microphone arrays of different physical sizes are used to acquire signals for spatial tracking of one or more sound sources within the environment. A first array with a larger size may be used to track an object beyond a threshold distance, while a second array having a size smaller than the first may be used to track the object up to the threshold distance. By selecting different sized arrays, accuracy of the spatial location is improved.
    Type: Grant
    Filed: March 13, 2015
    Date of Patent: November 8, 2016
    Assignee: Amazon Technologies, Inc.
    Inventors: Wai C. Chu, Edward Dietz Crump
  • Patent number: 9373338
    Abstract: An automatic speech recognition engine receives an acoustic-echo processed signal from an acoustic-echo processing (AEP) module, where said echo processed signal contains mainly the speech from the near-end talker. The automatic speech recognition engine analyzes the content of the acoustic-echo processed signal to determine whether words or keywords are present. Based upon the results of this analysis, the automatic speech recognition engine produces a value reflecting the likelihood that some words or keywords are detected. Said value is provided to the AEP module. Based upon the value, the AEP module determines if there is double talk and processes the incoming signals accordingly to enhance its performance.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: June 21, 2016
    Assignee: Amazon Technologies, Inc.
    Inventors: Ramya Gopalan, Kavitha Velusamy, Wai C. Chu, Amit S. Chhetri
  • Patent number: 9351089
    Abstract: Techniques are described for recognizing an audio double tap or other tapped audio sequences generated by a user. Amplitudes of an audio signal are processed to generate an energy function or curve. The energy curve is analyzed to detect audio pulses. Detected pulses are validated and double tap events are detected based on features such as duration, power, and/or symmetry, plus additional rules related to the structure of the audio event.
    Type: Grant
    Filed: March 14, 2012
    Date of Patent: May 24, 2016
    Assignee: Amazon Technologies, Inc.
    Inventor: Wai C. Chu
  • Patent number: 9081083
    Abstract: Accurate and computationally efficient estimation of time delay of arrival data for localization of a sound source is described herein. A number of independent time delays are retained and validated through comparison with a set of dependent time delays. The method is robust against detrimental effects in the environment such as noise and reverberation. The resulting delays may then be used in sound source localization or other signal processing applications.
    Type: Grant
    Filed: June 27, 2011
    Date of Patent: July 14, 2015
    Assignee: Amazon Technologies, Inc.
    Inventor: Wai C. Chu
  • Patent number: 8983089
    Abstract: An augmented reality environment allows interaction between virtual and real objects. Multiple microphone arrays of different physical sizes are used to acquire signals for spatial tracking of one or more sound sources within the environment. A first array with a larger size may be used to track an object beyond a threshold distance, while a second array having a size smaller than the first may be used to track the object up to the threshold distance. By selecting different sized arrays, accuracy of the spatial location is improved.
    Type: Grant
    Filed: November 28, 2011
    Date of Patent: March 17, 2015
    Assignee: Rawles LLC
    Inventors: Wai C. Chu, Edward Dietz Crump
  • Patent number: 8885815
    Abstract: A plurality of microphones of a communication device is grouped into multiple microphone groups, such that each microphone group includes two or more microphones. For each microphone group, output of the corresponding microphones is processed to form an acoustic null in a corresponding spatial direction, such that sound from the corresponding spatial direction is attenuated in the processed output. One of the microphone groups is selected based on various factors leading to maximal echo attenuation and rejection of reverberant components of the room. The selected microphone group is then used to detect sound from a near end talker of the communication device.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: November 11, 2014
    Assignee: Rawles LLC
    Inventors: Kavitha Velusamy, Amit S. Chhetri, Ramya Gopalan, Wai C. Chu, Wei Li
  • Patent number: 8855295
    Abstract: Techniques for utilizing blind source separation as a front-end to an acoustic echo canceller are described herein. The techniques include removing a first portion of an acoustic echo from an audio signal using blind source separation and a reference signal. The techniques then further remove a second portion of the acoustic echo using an acoustic echo canceller and the reference signal. Further, output of the blind source separation may be used to improve double-talk detection.
    Type: Grant
    Filed: June 25, 2012
    Date of Patent: October 7, 2014
    Assignee: Rawles LLC
    Inventors: Amit S. Chhetri, Kavitha Velusamy, Wai C. Chu, Ramya Gopalan
  • Patent number: 8582906
    Abstract: Compression and decompression of image data, including a first image of an object. The first image may be divided into portions. For each portion, it may be determined whether the portion includes a part of the object. The image data may be compressed based on said determining. If a threshold ratio of portions that do not include a part of the object is reached, portions including a part of the object may be compressed according to a first compression method and portions not including a part of the object may not be compressed, where background information is stored for the portions not including a part of the object. If the threshold ratio of portions that do not include a part of the object is not reached, each portion of the object may be compressed according to the first compression method. The compressed data may be decompressed in a reverse fashion.
    Type: Grant
    Filed: March 3, 2010
    Date of Patent: November 12, 2013
    Assignee: AOD Technology Marketing, LLC
    Inventors: Wai C. Chu, David J. Pattridge
  • Patent number: 8156898
    Abstract: An apparatus for acclimating an aquatic organism, contained in a partially water filled plastic bag, to an environment in an aquarium includes an aquarium frame comprising a first portion exterior to the aquarium and a second portion interior to the aquarium. A bag holder is operable to hold a top of the plastic bag in an open position. The bag holder is positioned on the second portion where the top of the plastic bag is above a top level of water in the aquarium and a substantial portion of the plastic bag is below the top level. A dripping cup is operable to release water obtained from the aquarium into the plastic bag. The dripping cup is joinable to the first portion, whereby the aquatic organism is acclimated to a chemistry and temperature of the water in the aquarium.
    Type: Grant
    Filed: November 20, 2008
    Date of Patent: April 17, 2012
    Inventors: Le Quan Luong, Wai C. Chu
  • Publication number: 20110216969
    Abstract: Compression and decompression of image data, including a first image of an object. The first image may be divided into portions. For each portion, it may be determined whether the portion includes a part of the object. The image data may be compressed based on said determining. If a threshold ratio of portions that do not include a part of the object is reached, portions including a part of the object may be compressed according to a first compression method and portions not including a part of the object may not be compressed, where background information is stored for the portions not including a part of the object. If the threshold ratio of portions that do not include a part of the object is not reached, each portion of the object may be compressed according to the first compression method. The compressed data may be decompressed in a reverse fashion.
    Type: Application
    Filed: March 3, 2010
    Publication date: September 8, 2011
    Inventors: Wai C. Chu, David J. Pattridge
  • Publication number: 20090139457
    Abstract: An apparatus for acclimating an aquatic organism, contained in a partially water filled plastic bag, to an environment in an aquarium includes an aquarium frame comprising a first portion exterior to the aquarium and a second portion interior to the aquarium. A bag holder is operable to hold a top of the plastic bag in an open position. The bag holder is positioned on the second portion where the top of the plastic bag is above a top level of water in the aquarium and a substantial portion of the plastic bag is below the top level. A dripping cup is operable to release water obtained from the aquarium into the plastic bag. The dripping cup is joinable to the first portion, whereby the aquatic organism is acclimated to a chemistry and temperature of the water in the aquarium.
    Type: Application
    Filed: November 20, 2008
    Publication date: June 4, 2009
    Inventors: Le Quan Luong, Wai C. Chu
  • Patent number: 7512534
    Abstract: Primary and alternate optimization procedures are used to improve the ITU-T G.723.1 speech coding standard (the “Standard”) by replacing the Hamming window of the Standard with an optimized window, with two windows, or with two windows and an additional performance of an autocorrelation method. When two windows replace the Hamming window, at least one of which is an optimized window, generally the first is used to determine optimized unquantized LP coefficients which are used to define an optimized perceptual weighting filter, and the second is used to determine optimized unquantized LP coefficients which are used to determine optimized synthesis coefficients. Optimized windows created using the primary and alternate optimization procedures and used in the Standard yield improvements in the objective and subjective quality of synthesized speech produced by the Standard. The improved Standard, methods, and widow can all be implemented as computer readable software code.
    Type: Grant
    Filed: November 9, 2006
    Date of Patent: March 31, 2009
    Assignee: NTT DoCoMo, Inc.
    Inventor: Wai C. Chu
  • Patent number: 7426470
    Abstract: A method for energy based, non-uniform time-scale compression of audio signals includes receiving a frame of data corresponding to an input audio signal and segmenting the data into a plurality of segments. The method further includes estimating a value related to energy of the frame of data, determining a peak energy estimate for the frame, determining an energy threshold based on the peak energy estimate of the frame and comparing the value related to energy of the frame of the data with the energy threshold to control time-scale compression of the audio data.
    Type: Grant
    Filed: October 3, 2002
    Date of Patent: September 16, 2008
    Assignee: NTT Docomo, Inc.
    Inventors: Wai C. Chu, Khosrow Lashkari
  • Patent number: 7389226
    Abstract: Primary and alternate optimization procedures are used to improve the ITU-T G.723.1 speech coding standard (the “Standard”) by replacing the Hamming window of the Standard with an optimized window, with two windows, or with two windows and an additional performance of an autocorrelation method. When two windows replace the Hamming window, at least one of which is an optimized window, generally the first is used to determine optimized unquantized LP coefficients which are used to define an optimized perceptual weighting filter, and the second is used to determine optimized unquantized LP coefficients which are used to determine optimized synthesis coefficients. Optimized windows created using the primary and alternate optimization procedures and used in the Standard yield improvements in the objective and subjective quality of synthesized speech produced by the Standard. The improved Standard, methods, and window can all be implemented as computer readable software code.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: June 17, 2008
    Assignee: NTT Docomo, Inc.
    Inventor: Wai C. Chu
  • Publication number: 20080133252
    Abstract: A method for energy based, non-uniform time-scale compression of audio signals includes receiving a frame of data corresponding to an input audio signal and segmenting the data into a plurality of segments. The method further includes estimating a value related to energy of the frame of data, determining a peak energy estimate for the frame, determining an energy threshold based on the peak energy estimate of the frame and comparing the value related to energy of the frame of the data with the energy threshold to control time-scale compression of the audio data.
    Type: Application
    Filed: January 9, 2008
    Publication date: June 5, 2008
    Inventors: Wai C. Chu, Khosrow Lashkari
  • Publication number: 20080133251
    Abstract: A method for energy based, non-uniform time-scale compression of audio signals includes receiving a frame of data corresponding to an input audio signal and segmenting the data into a plurality of segments. The method further includes estimating a value related to energy of the frame of data, determining a peak energy estimate for the frame, determining an energy threshold based on the peak energy estimate of the frame and comparing the value related to energy of the frame of the data with the energy threshold to control time-scale compression of the audio data.
    Type: Application
    Filed: January 9, 2008
    Publication date: June 5, 2008
    Inventors: Wai C. Chu, Khosrow Lashkari