| Patent Number |
Title Of Patent |
Date Issued |
| 8301440 |
Bit error concealment for audio coding systems |
October 30, 2012 |
| A bit error concealment (BEC) system and method is described herein that detects and conceals the presence of click-like artifacts in an audio signal caused by bit errors introduced during transmission of the audio signal within an audio communications system. A particular embodiment of |
| 8280728 |
Packet loss concealment for a sub-band predictive coder based on extrapolation of excitation wav |
October 2, 2012 |
| Systems and methods are described for performing packet loss concealment using an extrapolation of an excitation waveform in a sub-band predictive speech coder, such as an ITU-T Recommendation G.722 wideband speech coder. The systems and methods are useful for concealing the quality- |
| 8214206 |
Constrained and controlled decoding after packet loss |
July 3, 2012 |
| A technique is described herein for reducing audible artifacts in an audio output signal generated by decoding a received frame in a series of frames representing an encoded audio signal in a predictive coding system. In accordance with the technique, it is determined if the received |
| 8195465 |
Time-warping of decoded audio signal after packet loss |
June 5, 2012 |
| A technique is described for use in a decoder configured to decode a series of frames representing an encoded audio signal. The technique is for transitioning between a lost frame and one or more received frames following the lost frame in the series of frames. In accordance with the |
| 8078458 |
Packet loss concealment for sub-band predictive coding based on extrapolation of sub-band audio |
December 13, 2011 |
| A technique is described for concealing the effect of a lost frame in a series of frames representing an encoded audio signal in a sub-band predictive coding system. In accordance with the technique, a first synthesized sub-band audio signal is synthesized, wherein synthesizing the f |
| 8078456 |
Audio time scale modification algorithm for dynamic playback speed control |
December 13, 2011 |
| A modified synchronized overlap add (SOLA) algorithm for performing high-quality, low-complexity audio time scale modification (TSM) is described. The algorithm produces good output audio quality with a very low complexity and without producing additional audible distortion during dy |
| 8032363 |
Adaptive postfiltering methods and systems for decoding speech |
October 4, 2011 |
| A method of processing a decoded speech (DS) signal including successive DS frames, each DS frame including DS samples. The method comprises: adaptively filtering the DS signal to produce a filtered signal; gain-scaling the filtered signal with an adaptive gain updated once a DS fram |
| 8032360 |
System and method for high-quality variable speed playback of audio-visual media |
October 4, 2011 |
| A system and method for high-quality variable speed playback of audio-visual (A/V) media is provided. The system receives an encoded visual signal and an encoded audio signal. The encoded visual signal is decoded to generate a decoded visual signal and the encoded audio signal is dec |
| 8024192 |
Time-warping of decoded audio signal after packet loss |
September 20, 2011 |
| A technique is described for use in a decoder configured to decode a series of frames representing an encoded audio signal. The technique is for transitioning between a lost frame and one or more received frames following the lost frame in the series of frames. In accordance with the |
| 8015000 |
Classification-based frame loss concealment for audio signals |
September 6, 2011 |
| An audio decoding system performs frame loss concealment (FLC) when portions of a bit stream representing an audio signal are lost within the context of a digital communication system. The audio decoding system employs two different FLC methods: one designed to perform well for music |
| 8005678 |
Re-phasing of decoder states after packet loss |
August 23, 2011 |
| A technique is described herein for updating a state of a decoder configured to decode a series of frames representing an encoded audio signal. In accordance with the technique, an output audio signal associated with a lost frame in the series of frames is synthesized. The decoder st |
| 8000960 |
Packet loss concealment for sub-band predictive coding based on extrapolation of sub-band audio |
August 16, 2011 |
| A technique is described for concealing the effect of a lost frame in a series of frames representing an encoded audio signal in a sub-band predictive coding system. In accordance with the technique, a first synthesized sub-band audio signal is synthesized, wherein synthesizing the f |
| 7995775 |
Automatic volume control for audio signals |
August 9, 2011 |
| A technique is provided for automatically adjusting the volume, or magnitude, of an audio signal. The technique includes calculating an average power associated with a segment of an input audio signal, determining whether the average power is greater than an estimated signal level as |
| 7983720 |
Wireless telephone with adaptive microphone array |
July 19, 2011 |
| A wireless telephone having an array of microphones and a digital signal processor (DSP) and a method of processing audio signals from a wireless telephone having an array of microphones and a DSP. The wireless telephone includes an array of microphones and a DSP. Each microphone in |
| 7957960 |
Audio time scale modification using decimation-based synchronized overlap-add algorithm |
June 7, 2011 |
| A high-quality, low-complexity audio time scale modification (TSM) algorithm useful in speeding up or slowing down the playback of an encoded audio signal without changing the pitch or timbre of the audio signal. The TSM algorithm uses a modified synchronized overlap-add (SOLA) algor |
| 7930176 |
Packet loss concealment for block-independent speech codecs |
April 19, 2011 |
| A technique for performing frame erasure concealment (FEC) in a speech decoder. One or more non-erased frames of a speech signal are decoded in a block-independent manner. When an erased frame is detected, a short-term predictive filter and a long-term predictive filter are derived b |
| 7805297 |
Classification-based frame loss concealment for audio signals |
September 28, 2010 |
| A system and method for performing frame loss concealment (FLC) when portions of a bit stream representing an audio signal are lost within the context of a digital communication system. The system and method utilizes a plurality of different FLC techniques, wherein each technique is tune |
| 7752037 |
Pitch extraction methods and systems for speech coding using sub-multiple time lag extraction |
July 6, 2010 |
| A method of determining a pitch period of an audio signal using a correlation-based signal derived from the audio signal. The correlation-based signal includes known peaks each corresponding to a respective one of known time lags. The known peaks includes a global maximum peak. The m |
| 7711563 |
Method and system for frame erasure concealment for predictive speech coding based on extrapolat |
May 4, 2010 |
| A method and system are provided for synthesizing a corrupted frame output from a decoder including one or more predictive filters. The corrupted frame is representative of one segment of a decoded signal output from the decoder. The method comprises extrapolating a replacement frame bas |
| 7684521 |
Apparatus and method for hybrid decoding |
March 23, 2010 |
| Typical communication systems operate with a single channel decoder, and hence would have to settle for the performance from the single channel decoder regardless of the conditions of the communications channel. The present invention uses a hybrid channel decoder comprising multiple |
| 7590525 |
Frame erasure concealment for predictive speech coding based on extrapolation of speech waveform |
September 15, 2009 |
| A method and system are provided for synthesizing a number of corrupted frames output from a decoder including one or more predictive filters. The corrupted frames are representative of one segment of a decoded signal (sq(n)) output from the decoder. The method comprises determining |
| 7529661 |
Pitch extraction methods and systems for speech coding using quadratically-interpolated and filt |
May 5, 2009 |
| A method of attempting to determine a pitch period of an audio signal using a correlation-based signal derived from the audio signal. The correlation-based signal has known peaks, having been quadratically interpolated and filtered with coefficients that are a function of the interpo |
| 7512535 |
Adaptive postfiltering methods and systems for decoding speech |
March 31, 2009 |
| A filter controller processes a decoded speech (DS) signal. The DS signal has a spectral envelope including a first plurality of formant peaks having different respective amplitudes. The controller produces, from the DS signal, a spectrally-flattened DS signal that is a time-domain signa |
| 7496506 |
Method and apparatus for one-stage and two-stage noise feedback coding of speech and audio signa |
February 24, 2009 |
| Codec structures for achieving two-stage prediction and two-stage noise spectral shaping at the same time, resulting in a Two-Stage Noise Feedback Coding (TSNFC) method. One approach combines two predictors into a single composite predictor; and derives appropriate filters for use in |
| 7478040 |
Method for adaptive filtering |
January 13, 2009 |
| A method for adaptive long-term filtering of an audio signal, such as a decoded speech signal. The method includes measuring a smoothed periodicity of an audio signal segment, such as an audio frame, wherein the smoothed periodicity is measured by low-pass filtering an instantaneous |
| 7406411 |
Bit error concealment methods for speech coding |
July 29, 2008 |
| A system and method of concealing bit errors in a signal are provided. An exemplary method detects bit errors in an input signal having at least a current signal segment and a previous signal segment. The previous signal segment has a log-gain value qlg(m-1) and immediately precedes the |
| 7378995 |
Low-complexity sampling rate conversion method and apparatus for audio processing |
May 27, 2008 |
| A low-complexity sampling rate conversion (SRC) method and apparatus for the processing of digital audio signals. A first stage upsamples an input audio signal to generate an upsampled audio signal. For example, the first stage may perform 1:2 upsampling using a halfband filter. A second |
| 7353168 |
Method and apparatus to eliminate discontinuities in adaptively filtered signals |
April 1, 2008 |
| A method to eliminate discontinuities in an adaptively filtered signal includes filtering a beginning portion of a current signal frame using a past set of filter coefficients, thereby producing a first filtered frame portion. The method also includes filtering the beginning portion of t |
| 7324937 |
Method for packet loss and/or frame erasure concealment in a voice communication system |
January 29, 2008 |
| A method for performing packet loss concealment (PLC) and/or frame erasure concealment (FEC) in a speech decoder of a voice communication system. In accordance with the method, if a segment of an encoded speech signal is determined to be bad, an excitation signal is derived by scaling a |
| 7308406 |
Method and system for a waveform attenuation technique for predictive speech coding based on ext |
December 11, 2007 |
| A method and system are provided for processing an extrapolated signal including a number of consecutive replacement frames. The method comprises attenuating a portion of the extrapolated signal when the extrapolated signal reaches a predetermined duration. The attenuating produces a |
| 7236927 |
Pitch extraction methods and systems for speech coding using interpolation techniques |
June 26, 2007 |
| A method of searching for an interpolated peak of a Normalized Correlation Square (NCS) signal derived from an audio signal, comprises: producing quadratically interpolated correlation (QIC) signal values at interpolated time lags; squaring each of the QIC signal values to produce sq |
| 7209878 |
Noise feedback coding method and system for efficiently searching vector quantization codevector |
April 24, 2007 |
| A system for performing a computationally efficient method of searching through N Vector Quantization (VQ) codevectors for a preferred one of the N VQ codevectors predicts a speech signal to derive a residual signal, derives a ZERO-INPUT response error vector common to each of the N VQ |
| 7206740 |
Efficient excitation quantization in noise feedback coding with general noise shaping |
April 17, 2007 |
| In a Noise Feedback Coding (NFC) system operable in a ZERO-STATE condition and a ZERO-INPUT condition, the NFC system including at least one filter having a filter memory, a method of updating the filter memory. The method comprises: (a) producing a ZERO-STATE contribution to the filter |
| 7180435 |
Low-complexity sampling rate conversion method and apparatus for audio processing |
February 20, 2007 |
| A low-complexity sampling rate conversion (SRC) method and apparatus for the processing of digital audio signals. A first stage upsamples an input audio signal to generate an upsampled audio signal. For example, the first stage may perform 1:2 upsampling using a halfband filter. A second |
| 7171355 |
Method and apparatus for one-stage and two-stage noise feedback coding of speech and audio signa |
January 30, 2007 |
| Codec structures for achieving two-stage prediction and two-stage noise spectral shaping at the same time, resulting in a Two-Stage Noise Feedback Coding (TSNFC) method. One approach combines two predictors into a single composite predictor; and derives appropriate filters for use in |
| 7143032 |
Method and system for an overlap-add technique for predictive decoding based on extrapolation of |
November 28, 2006 |
| A method and system are provided for removing discontinuities associated with synthesizing a corrupted frame output from a decoder including one or more predictive filters. The corrupted frame is representative of one segment of a decoded signal. The method comprises copying a first numb |
| 7110942 |
Efficient excitation quantization in a noise feedback coding system using correlation techniques |
September 19, 2006 |
| A method of performing an excitation Vector Quantization (VQ) in a Noise Feedback Coding environment involves reorganizing a calculation of an energy of an error vector for each of a plurality of candidate excitation vectors of a codebook. The energy of the error vector is a cost functio |
| 6980951 |
Noise feedback coding method and system for performing general searching of vector quantization |
December 27, 2005 |
| A method of searching a plurality of Vector Quantization (VQ) codevectors for a preferred one of the VQ codevectors to be used as an output of a vector quantizer for encoding a speech signal, includes determining a quantized prediction residual vector, and calculating a corresponding |
| 6885988 |
Bit error concealment methods for speech coding |
April 26, 2005 |
| A method of concealing bit errors in a signal is provided. The method comprises encoding a signal parameter according to a set of constraints placed on a signal parameter quantizer. The encoded signal parameter is decoded and compared against the set of constraints. Finally, the method |
| 6751587 |
Efficient excitation quantization in noise feedback coding with general noise shaping |
June 15, 2004 |
| In a Noise Feedback Coding (NFC) system having a corresponding ZERO-STATE filter structure, the first ZERO-STATE filter structure including multiple filters, a method of producing a ZERO-STATE response error vector. The method includes: (a) transforming the first ZERO-STATE filter struct |
