|
Match
|
Document |
Document Title |
|
|
6556966 |
Codebook structure for changeable pulse multimode speech coding
A speech compression system with a special fixed codebook structure and a new search routine is proposed for speech coding. The system is capable of encoding a speech signal into a bitstream for...
|
|
|
6539349 |
Constraining pulse positions in CELP vocoding
An apparatus and method for vocoding an input signal comprising a linear predictive filter for generating a filtered signal with a first signal pulse and a second signal pulse in response to...
|
|
|
6535845 |
Processing an audio bitstream signal
A data processing apparatus includes an input terminal for receiving an audio signal, a 1-bit A/D converter for A/D converting the audio signal into a 1-bit bitstream signal, and a prediction unit...
|
|
|
6526376 |
Split band linear prediction vocoder with pitch extraction
A speech coder includes an encoder using an analysis and synthesis approach. The encoder uses a pitch determination algorithm requiring analysis in both the frequency domain and the time domain, a...
|
|
|
6523002 |
Speech coding having continuous long term preprocessing without any delay
A zero delay continuous long term (LT) pre-processing method operable in a speech codec that introduces no delay. The present invention provides an elegant solution to perform long term (LT)...
|
|
|
6509850 |
Method and system for sampling rate conversion in digital audio applications
A method for upsampling a digital audio signal is described. The method includes receiving a first digital audio signal including samples and having a first sampling rate. The method also includes...
|
|
|
6507814 |
Pitch determination using speech classification and prior pitch estimation
A multi-rate speech codec supports a plurality of encoding bit rate modes by adaptively selecting encoding bit rate modes to match communication channel restrictions. In higher bit rate encoding...
|
|
|
6502069 |
Method and a device for coding audio signals and a method and a device for decoding a bit stream
The present invention permits a combination of a scalable audio coder with the TNS technique. In a method for coding time signals sampled in a first sampling rate, second time signals are first...
|
|
|
6502068 |
Multipulse search processing method and speech coding apparatus
A speech coding apparatus includes a pulse position candidate table, inter-pulse distortion table, first and second reference address tables, first and second reference address table creation...
|
|
|
6499010 |
Perceptual audio coder bit allocation scheme providing improved perceptual quality consistency
A method (and apparatus) for coding an audio signal, the method comprising the steps of partitioning the audio signal into a sequence of successive frames; calculating one or more noise thresholds...
|
|
|
6496796 |
Voice coding apparatus and voice decoding apparatus
Drive sound source coding means, decoding means has a plurality of algebraic sound source coding means, decoding means having sound source position tables different in distribution lean of sound...
|
|
|
6487527 |
Enhanced quantization method for spectral frequency coding
A linear predictive speech encoding method combines vector quantization with the search for roots of LSP polynomials. At Under this method, a code book searchable using line spectral pair (LSP)...
|
|
|
6484138 |
Method and apparatus for performing speech frame encoding mode selection in a variable rate encoding system
It is an objective of the present invention to provide an optimized method of selection of the encoding mode that provides rate efficient coding of the input speech. It is a second objective of the...
|
|
|
6475245 |
Method and apparatus for hybrid coding of speech at 4KBPS having phase alignment between mode-switched frames
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...
|
|
|
6470312 |
Speech coding apparatus, speech processing apparatus, and speech processing method
The invention enables a source speech signal to be coded in an optimal way. An adaptive codebook (Ba) stores a series of signal vectors of a past speech signal. A vector extraction means extracts a...
|
|
|
6470311 |
Method and apparatus for determining pitch synchronous frames
In a speech processing system, an optimal filter frequency is determined and used to filter an unfiltered signal. The optimum filter is chosen by passing the largest voice area greater than 50 ms...
|
|
|
6463409 |
METHOD OF AND APPARATUS FOR DESIGNING CODE BOOK OF LINEAR PREDICTIVE PARAMETERS, METHOD OF AND APPARATUS FOR CODING LINEAR PREDICTIVE PARAMETERS, AND PROGRAM STORAGE DEVICE READABLE BY THE DESIGNING APPARATUS
A code book is a set of code vectors to be selected when linear predictive parameters are vector-quantized as for an input audio which is divided into frames, each of which is further divided into...
|
|
|
6456964 |
Encoding of periodic speech using prototype waveforms
A method and apparatus for coding a quasi-periodic speech signal. The speech signal is represented by a residual signal generated by filtering the speech signal with a Linear Predictive Coding...
|
|
|
6453287 |
Apparatus and quality enhancement algorithm for mixed excitation linear predictive (MELP) and other speech coders
A system and method for enhancing the speech quality of the mixed excitation linear predictive (MELP) coder and other low bit-rate speech coders. The system and method employ a plosive...
|
|
|
6449313 |
Shaped fixed codebook search for celp speech coding
A fixed codebook response is able to better characterize an input signal of a vocoder because the entries of the fixed codebook are tailored to the input signal being processed. A uniformly...
|
|
|
6449590 |
Speech encoder using warping in long term preprocessing
A multi-rate speech codec supports a plurality of encoding bit rate modes by adaptively selecting encoding bit rate modes to match communication channel restrictions. In higher bit rate encoding...
|
|
|
6438518 |
Method and apparatus for using coding scheme selection patterns in a predictive speech coder to reduce sensitivity to frame error conditions
A method and apparatus for using coding scheme selection patterns in a predictive speech coder to reduce sensitivity to frame error conditions includes a speech coder configured to select from...
|
|
|
6430530 |
Apparatus for automatically processing both encoded and unencoded data
An apparatus for automatically rendering both encoded and unencoded data files comprises a data processor and a decoder. The data processor receives a set of input data from a storage medium, such...
|
|
|
6424941 |
Adaptively compressing sound with multiple codebooks
Compression of speech may be achieved through the adaptive generation of a compressed sound output. A first processing element may be used to characterize a first sound representation such that a...
|
|
|
6424939 |
Method for coding an audio signal
A method for coding or decoding an audio signal combines the advantages of TNS processing and noise substitution. A time-discrete audio signal is initially transformed to the frequency domain in...
|
|
|
6424940 |
Method and system for determining gain scaling compensation for quantization
A method and system for reducing prediction error impulses using a gain average calculator, an impulse detector, a signal classifier decision means and a gain compensator wherein the compensated...
|
|
|
6418406 |
Synthesis of high-pitched sounds
An improvement in the synthesis of high-pitched voices and sounds is provided by downshifting the pitch 11 of the original input voice or sound before LPC analysis 13. This downshifting of the...
|
|
|
6418407 |
Method and apparatus for pitch determination of a low bit rate digital voice message
A pitch determiner ( 931 ) of a system controller ( 106 ) that generates a smoothed pitch value for a current frame of a low bit rate voice message includes a pitch function generator ( 955 ) that...
|
|
|
6418408 |
Frequency domain interpolative speech codec system
Encoding of prototype waveform components applicable to GeoMobile and Telephony Earth Station (TES) providing improved voice quality enabling a dual-channel mode of operation which permits more...
|
|
|
6415254 |
Sound encoder and sound decoder
An excitation vector generator comprises a pulse vector generating section having N channels (N≧1) for generating pulse vectors, a storing section for storing M (M≧1)kinds of dispersion...
|
|
|
6389388 |
Encoding a speech signal using code excited linear prediction using a plurality of codebooks
A speech signal is encoded using code excited linear prediction for use in transmitting the speech signal to a receiver. The speech signal is sampled. A current sample of the speech signal is...
|
|
|
6385573 |
Adaptive tilt compensation for synthesized speech residual
A multi-rate speech codec supports a plurality of encoding bit rate modes by adaptively selecting encoding bit rate modes to match communication channel restrictions. In higher bit rate encoding...
|
|
|
6385577 |
Multiple impulse excitation speech encoder and decoder
A version of a speech signal and an output of a pitch synthesis filter and a linear predictive all-pole (LPC) filter is received. A system impulse response is produced based on in part the received...
|
|
|
6385578 |
Method for eliminating annoying noises of enhanced variable rate codec (EVRC) during error packet processing
A decoding method of an Enhanced Variable Rate Codec (EVRC) is provided for reducing EVRC noises during error packet processing in a CDMA system. The method induces setting a seed value for...
|
|
|
6385576 |
Speech encoding/decoding method using reduced subframe pulse positions having density related to pitch
A speech encoding method in which information representing characteristics of a synthesis filter is generated based on an input speech signal in units of one frame. A pitch vector is generated from...
|
|
|
6377923 |
Speech recognition method and system using compression speech data
A vocoder based voice recognizer recognizes a spoken word using linear prediction coding (LPC) based, vocoder data without completely reconstructing the voice data. The recognizer generates at...
|
|
|
6366881 |
Voice encoding method
In a voice coding method for adaptively quantizing a difference d n between an input signal x n and a predicted value y n to code the difference, adaptive quantization is performed such that a...
|
|
|
6363341 |
Encoder for minimizing resulting effect of transmission errors
A transmission system comprising a transmitter with a signal encoder, the signal encoder having an input for a signal to be encoded and a codebook entry selector for selecting a codebook entry for...
|
|
|
6363340 |
Transmission system with improved speech encoder
A speech transmission system with an input speech signal applied to a speech encoder for encoding the speech signal which is transmitted via a communication channel to a speech decoder. Background...
|
|
|
6360200 |
Process for reducing redundancy during the coding of multichannel signals and device for decoding redundancy-reduced multichannel signals
A redundance reduction method used in coding multichannel signals is proposed, where signals available in digitized form are predicted. A prediction error is computed, which is subsequently...
|
|
|
6351730 |
Low-complexity, low-delay, scalable and embedded speech and audio coding with adaptive frame loss concealment
High-quality, low-complexity and low-delay scalable and embedded system and method are disclosed for coding speech and general audio signals. The invention is particularly suitable in Internet...
|
|
|
6345248 |
Low bit-rate speech coder using adaptive open-loop subframe pitch lag estimation and vector quantization
A pitch lag coding device and method using interframe correlation inherent in pitch lag values to reduce coding bit requirements. A pitch lag value is extracted for a given speech frame, and then...
|
|
|
6345246 |
Apparatus and method for efficiently coding plural channels of an acoustic signal at low bit rates
In multichannel acoustic signal coding and decoding, left- and right-channel signals are alternately interleaved for each sample to generate a one-dimensional signal sample sequence. The...
|
|
|
6339757 |
Bit allocation method for digital audio signals
When determining a quantization for digital audio signals having a spectral and temporal structure wherein the audio signals are buffered in frames and decomposed into spectral components, the...
|
|
|
6330533 |
Speech encoder adaptively applying pitch preprocessing with warping of target signal
A multi-rate speech codec supports a plurality of encoding bit rate modes by adaptively selecting encoding bit rate modes to match communication channel restrictions. In higher bit rate encoding...
|
|
|
6330532 |
Method and apparatus for maintaining a target bit rate in a speech coder
A method and apparatus for maintaining a target bit rate in a speech coder includes a speech coder for encoding a frame at a preselected encoding rate, computing a running average bit rate for a...
|
|
|
6327562 |
Method and device for coding an audio signal by "forward" and "backward" LPC analysis
A method and device for encoding a digital audio-signal divided into a succession of blocks according to a LPC "forward" and "backward" analysis respectively under a choice criterion. For coding...
|
|
|
6311154 |
Adaptive windows for analysis-by-synthesis CELP-type speech coding
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...
|
|
|
6311153 |
Speech recognition method and apparatus using frequency warping of linear prediction coefficients
An audio signal compression apparatus for compressively coding an input audio signal comprises a time-to-frequency transformation unit for transforming the input audio signal to a frequency domain...
|
|
|
6304843 |
Method and apparatus for reconstructing a linear prediction filter excitation signal
An apparatus and method of reconstructing a linear prediction synthesis filter excitation signal, by: receiving a signal representative of output from a linear prediction synthesis filter,...
|