Patents by Inventor Allen Gersho
Allen Gersho 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).
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Patent number: 7584095Abstract: An enhanced analysis-by-synthesis waveform interpolative speech coder able to operate at 2.8 kbps. Novel features include dual-predictive analysis-by-synthesis quantization of the slowly-evolving waveform, efficient parametrization of the rapidly-evolving waveform magnitude, and analysis-by-synthesis vector quantization of the rapidly evolving waveform parameter. Subjective quality tests indicate that it exceeds G.723.1 at 5.3 kbps, and of G.723.1 at 6.3 kbps.Type: GrantFiled: September 23, 2005Date of Patent: September 1, 2009Assignee: The Regents of the University of CaliforniaInventors: Oded Gottesman, Allen Gersho
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Patent number: 7315815Abstract: An enhanced low-bit rate parametric voice coder that groups a number of frames from an underlying frame-based vocoder, such as MELP, into a superframe structure. Parameters are extracted from the group of underlying frames and quantized into the superframe which allows the bit rate of the underlying coding to be reduced without increasing the distortion. The speech data coded in the superframe structure can then be directly synthesized to speech or may be transcoded to a format so that an underlying frame-based vocoder performs the synthesis. The superframe structure includes additional error detection and correction data to reduce the distortion caused by the communication of bit errors.Type: GrantFiled: September 22, 1999Date of Patent: January 1, 2008Assignee: Microsoft CorporationInventors: Allen Gersho, Vladimir Cuperman, Tian Wang, Kazuhito Koishida
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Patent number: 7286982Abstract: An enhanced low-bit rate parametric voice coder that groups a number of frames from an underlying frame-based vocoder, such as MELP, into a superframe structure. Parameters are extracted from the group of underlying frames and quantized into the superframe which allows the bit rate of the underlying coding to be reduced without increasing the distortion. The speech data coded in the superframe structure can then be directly synthesized to speech or may be transcoded to a format so that an underlying frame-based vocoder performs the synthesis. The superframe structure includes additional error detection and correction data to reduce the distortion caused by the communication of bit errors.Type: GrantFiled: July 20, 2004Date of Patent: October 23, 2007Assignee: Microsoft CorporationInventors: Allen Gersho, Vladimir Cuperman, Tian Wang, Kazuhito Koishida
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Patent number: 7124077Abstract: A method and system of performing postfiltering in the frequency domain to improve the quality of a speech signal, especially for synthesized speech resulting from codecs of low bit-rate, is provided. The method comprises LPC tilt computation and compensation methods and modules, a formant filter gain computation method and module, and an anti-aliasing method and module. The formant filter gain calculation employs an LPC representation, an all-pole modeling, a non-linear transformation and a phase computation. The LPC used for deriving the postfilter may be transmitted from an encoder or may be estimated from a synthesized or other speech signal in a decoder or receiver. The invention may be implemented in a linked decoder and encoder. A separate LPC evaluation unit that is responsible for processing and or deriving the LPC may be implemented within the invention.Type: GrantFiled: January 28, 2005Date of Patent: October 17, 2006Assignee: Microsoft CorporationInventors: Hong Wang, Vladimir Cuperman, Allen Gersho, Hosam A. Khalil
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Publication number: 20060069554Abstract: An enhanced analysis-by-synthesis waveform interpolative speech coder able to operate at 2.8 kbps. Novel features include dual-predictive analysis-by-synthesis quantization of the slowly-evolving waveform, efficient parametrization of the rapidly-evolving waveform magnitude, and analysis-by-synthesis vector quantization of the rapidly evolving waveform parameter. Subjective quality tests indicate that it exceeds G.723.1 at 5.3 kbps, and of G.723.1 at 6.3 kbps.Type: ApplicationFiled: September 23, 2005Publication date: March 30, 2006Inventors: Oded Gottesman, Allen Gersho
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Patent number: 7010482Abstract: An enhanced analysis-by-synthesis waveform interpolative speech coder able to operate at 2.8 kbps. Novel features include dual-predictive analysis-by-synthesis quantization of the slowly-evolving waveform, efficient parametrization of the rapidly-evolving waveform magnitude, and analysis-by-synthesis vector quantization of the rapidly evolving waveform parameter. Subjective quality tests indicate that it exceeds G.723.1 at 5.3 kbps, and of G.723.1 at 6.3 kbps.Type: GrantFiled: March 16, 2001Date of Patent: March 7, 2006Assignee: The Regents of the University of CaliforniaInventors: Oded Gottesman, Allen Gersho
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Patent number: 6941263Abstract: A method and system of performing postfiltering in the frequency domain to improve the quality of a speech signal, especially for synthesized speech resulting from codecs of low bit-rate, is provided. The method comprises LPC tilt computation and compensation methods and modules, a formant filter gain computation method and module, and an anti-aliasing method and module. The formant filter gain calculation employs an LPC representation, an all-pole modeling, a non-linear transformation and a phase computation. The LPC used for deriving the postfilter may be transmitted from an encoder or may be estimated from a synthesized or other speech signal in a decoder or receiver. The invention may be implemented in a linked decoder and encoder. A separate LPC evaluation unit that is responsible for processing and or deriving the LPC may be implemented within the invention.Type: GrantFiled: June 29, 2001Date of Patent: September 6, 2005Assignee: Microsoft CorporationInventors: Hong Wang, Vladimir Cuperman, Allen Gersho, Hosam A. Khalil
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Publication number: 20050131696Abstract: A method and system of performing postfiltering in the frequency domain to improve the quality of a speech signal, especially for synthesized speech resulting from codecs of low bit-rate, is provided. The method comprises LPC tilt computation and compensation methods and modules, a formant filter gain computation method and module, and an anti-aliasing method and module. The formant filter gain calculation employs an LPC representation, an all-pole modeling, a non-linear transformation and a phase computation. The LPC used for deriving the postfilter may be transmitted from an encoder or may be estimated from a synthesized or other speech signal in a decoder or receiver. The invention may be implemented in a linked decoder and encoder. A separate LPC evaluation unit that is responsible for processing and or deriving the LPC may be implemented within the invention.Type: ApplicationFiled: January 28, 2005Publication date: June 16, 2005Applicant: Microsoft CorporationInventors: Hong Wang, Vladimir Cuperman, Allen Gersho, Hosam Khalil
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Publication number: 20050075869Abstract: An enhanced_low-bit rate parametric voice coder that groups a number of frames from an underlying frame-based vocoder, such as MELP, into a superframe structure. Parameters are extracted from the group of underlying frames and quantized into the superframe which allows the bit rate of the underlying coding to be reduced without increasing the distortion. The speech data coded in the superframe structure can then be directly synthesized to speech or may be transcoded to a format so that an underlying frame-based vocoder performs the synthesis. The superframe structure includes additional error detection and correction data to reduce the distortion caused by the communication of bit errors.Type: ApplicationFiled: July 20, 2004Publication date: April 7, 2005Applicant: Microsoft CorporationInventors: Allen Gersho, Vladimir Cuperman, Tian Wang, Kazuhito Koishida
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Patent number: 6658383Abstract: The present invention provides a transform coding method efficient for music signals that is suitable for use in a hybrid codec, whereby a common Linear Predictive (LP) synthesis filter is employed for both speech and music signals. The LP synthesis filter switches between a speech excitation generator and a transform excitation generator, in accordance with the coding of a speech or music signal, respectively. For coding speech signals, the conventional CELP technique may be used, while a novel asymmetrical overlap-add transform technique is applied for coding music signals. In performing the common LP synthesis filtering, interpolation of the LP coefficients is conducted for signals in overlap-add operation regions. The invention enables smooth transitions when the decoder switches between speech and music decoding modes.Type: GrantFiled: June 26, 2001Date of Patent: December 2, 2003Assignee: Microsoft CorporationInventors: Kazuhito Koishida, Vladimir Cuperman, Amir H. Majidimehr, Allen Gersho
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Patent number: 6625226Abstract: A variable bit rate coder, and an associated method, for encoding a frame of speech, such as frames of data generated during operation of a communication station operable in a cellular communication system. Selection of the coding rate is made responsive to indicia of actual coding performance of a coder at more than one coding rate.Type: GrantFiled: December 3, 1999Date of Patent: September 23, 2003Inventors: Allen Gersho, Vladimir Cuperman, Jan Linden, Ajit V. Rao, Sassan Ahmadi, Fenghua Liu, Ryan Heidari
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Publication number: 20030009326Abstract: A method and system of performing postfiltering in the frequency domain to improve the quality of a speech signal, especially for synthesized speech resulting from codecs of low bit-rate, is provided. The method comprises LPC tilt computation and compensation methods and modules, a formant filter gain computation method and module, and an anti-aliasing method and module. The formant filter gain calculation employs an LPC representation, an all-pole modeling, a non-linear transformation and a phase computation. The LPC used for deriving the postfilter may be transmitted from an encoder or may be estimated from a synthesized or other speech signal in a decoder or receiver. The invention may be implemented in a linked decoder and encoder. A separate LPC evaluation unit that is responsible for processing and or deriving the LPC may be implemented within the invention.Type: ApplicationFiled: June 29, 2001Publication date: January 9, 2003Applicant: Microsoft CorporationInventors: Hong Wang, Vladimir Cuperman, Allen Gersho, Hosam A. Khalil
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Publication number: 20030004711Abstract: The present invention provides a transform coding method efficient for music signals that is suitable for use in a hybrid codec, whereby a common Linear Predictive (LP) synthesis filter is employed for both speech and music signals. The LP synthesis filter switches between a speech excitation generator and a transform excitation generator, in accordance with the coding of a speech or music signal, respectively. For coding speech signals, the conventional CELP technique may be used, while a novel asymmetrical overlap-add transform technique is applied for coding music signals. In performing the common LP synthesis filtering, interpolation of the LP coefficients is conducted for signals in overlap-add operation regions. The invention enables smooth transitions when the decoder switches between speech and music decoding modes.Type: ApplicationFiled: June 26, 2001Publication date: January 2, 2003Applicant: Microsoft CorporationInventors: Kazuhito Koishida, Vladimir Cuperman, Amir H. Majidimehr, Allen Gersho
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Patent number: 6475245Abstract: A method and apparatus for encoding speech for communication to a decoder for reproduction of the speech where the speech signal is classified into steady state voiced (harmonic), stationary unvoiced, and “transitory” or “transition” speech, and a particular type of coding scheme is used for each class. Harmonic coding is used for steady state voiced speech, “noise-like” coding is used for stationary unvoiced speech, and a special coding mode is used for transition speech, designed to capture the location, the structure, and the strength of the local time events that characterize the transition portions of the speech. The compression schemes can be applied to the speech signal or to the LP residual signal.Type: GrantFiled: February 5, 2001Date of Patent: November 5, 2002Assignee: The Regents of the University of CaliforniaInventors: Allen Gersho, Eyal Shlomot, Vladimir Cuperman, Chunyan Li
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Publication number: 20020116184Abstract: An enhanced analysis-by-synthesis waveform interpolative speech coder able to operate at 2.8 kbps. Novel features include dual-predictive analysis-by-synthesis quantization of the slowly-evolving waveform, efficient parametrization of the rapidly-evolving waveform magnitude, and analysis-by-synthesis vector quantization of the rapidly evolving waveform parameter. Subjective quality tests indicate that it exceeds G.723.1 at 5.3 kbps, and of G.723.1 at 6.3 kbps.Type: ApplicationFiled: March 16, 2001Publication date: August 22, 2002Inventors: Oded Gottsman, Allen Gersho
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Patent number: 6311154Abstract: A speech coder and a method for speech coding wherein the speech signal is represented by an excitation signal applied to a synthesis filter. The speech is partitioned into frames and subframes. A classifier identifies which of several categories the speech frame belongs to, and a different coding method is applied to represent the excitation for each category. For some categories, one or more windows are identified for the frame where all or most of the excitation signal samples are assigned by a coding scheme. Performance is enhanced by coding the important segments of the excitation more accurately. The window locations are determined from a linear prediction residual by identifying peaks of the smoothed residual energy contour. The method adjusts the frame and subframe boundaries so that each window is located entirely within a modified subframe or frame.Type: GrantFiled: December 30, 1998Date of Patent: October 30, 2001Assignee: Nokia Mobile Phones LimitedInventors: Allen Gersho, Vladimir Cuperman, Ajit V Rao, Tung-Chiang Yang, Sassan Ahmadi, Fenghua Liu
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Publication number: 20010023396Abstract: A method and apparatus for encoding speech for communication to a decoder for reproduction of the speech where the speech signal is classified into steady state voiced (harmonic), stationary unvoiced, and “transitory” or “transition” speech, and a particular type of coding scheme is used for each class. Harmonic coding is used for steady state voiced speech, “noise-like” coding is used for stationary unvoiced speech, and a special coding mode is used for transition speech, designed to capture the location, the structure, and the strength of the local time events that characterize the transition portions of the speech. The compression schemes can be applied to the speech signal or to the LP residual signal.Type: ApplicationFiled: February 5, 2001Publication date: September 20, 2001Inventors: Allen Gersho, Eyal Shlomot, Vladimir Cuperman, Chunyan Li
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Patent number: 6233550Abstract: A method and apparatus for encoding speech for communication to a decoder for reproduction of the speech where the speech signal is classified into steady state voiced (harmonic), stationary unvoiced, and “transitory” or “transition” speech, and a particular type of coding scheme is used for each class. Harmonic coding is used for steady state voiced speech, “noise-like” coding is used for stationary unvoiced speech, and a special coding mode is used for transition speech, designed to capture the location, the structure, and the strength of the local time events that characterize the transition portions of the speech. The compression schemes can be applied to the speech signal or to the LP residual signal.Type: GrantFiled: August 28, 1998Date of Patent: May 15, 2001Assignee: The Regents of the University of CaliforniaInventors: Allen Gersho, Eyal Shlomot, Vladimir Cuperman, Chunyan Li
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Patent number: 5889891Abstract: Vectors associated with multiple sources are quantized with a codebook. A mapping function associates each source with a subset of codevectors in the codebook, each subset being defined prior to quantization. Each vector from a source is matched to a codevector in the subset corresponding to the source. The universal codebook is designed by first providing a codebook and a mapping function. Using the codebook, the mapping function is updated by identifying subsets that reduce distortion when vectors from a source are quantized using a corresponding subset.Type: GrantFiled: November 21, 1995Date of Patent: March 30, 1999Assignee: Regents of the University of CaliforniaInventors: Allen Gersho, Kenneth Rose, Sangeeta Ramakrishnan
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Patent number: 5890110Abstract: A variable dimension vector quantization method that uses a single "universal" codebook. The method can be given the interpretation of sampling full-dimensioned codevectors in the universal codebook and generating subcodevectors of the same dimension as input data subvector, which dimension may vary in time. A subcodevector is selected from the codebook to have minimum distortion between it and the input data subvector. The subcodevector with minimum distortion corresponds to the representative, full-dimensioned codevector in the codebook. The codebook is designed by inverse sampling of training subvectors to obtain full-dimension vectors, then iteratively clustering the training set until a stable centroid vector is obtained.Type: GrantFiled: March 27, 1995Date of Patent: March 30, 1999Assignee: The Regents of the University of CaliforniaInventors: Allen Gersho, Amitava Das, Ajit Venkat Rao