Matches 201 - 250 out of 344 < 1 2 3 4 5 6 7 >
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6067518 Linear prediction speech coding apparatus  
A sample speech is analyzed by a speech analyzing unit to obtain sample characteristic parameters, and a coding distortion is calculated from the sample characteristic parameters in each of a...
6064956 Method to determine the excitation pulse positions within a speech frame  
A determination is made of the positions within a speech frame for a given number of excitation pulses in a linear predictive speech encoder. A combination of two known methods is used. The...
6058361 Two-stage Hierarchical subband coding and decoding system, especially for a digitized audio signal  
6041297 Vocoder for coding speech by using a correlation between spectral magnitudes and candidate excitations  
A vocoder according to the present invention includes an analyzer portion and a synthesizer portion. The analyzer portion encodes an input frame of speech on the basis of a candidate excitation...
6038530 Communication network for transmitting speech signals  
In a speech communication network in which a transmitter (1) transmits speech signals via a network (4) to a receiver (8), it can happen that more traffic is offered to the network (4) than it can...
6034971 Method and apparatus for controlling communication system capacity  
Forward link communication capacity of a communication system, which is providing from a base station to a number of mobile stations a number of forward communication links corresponding to the...
6029128 Speech synthesizer  
A post-processor 317 and method substantially for enhancing synthesised speech is disclosed. The post-processor 317 operates on a signal ex(n) derived from an excitation generator 211 typically...
6023672 Speech coder  
An excitation quantizer 60 in a speech encoder includes a divider, which divides M pulses representing in combination a speech signal into groups each of L pulses, L being smaller than M. The...
6016468 Generating the variable control parameters of a speech signal synthesis filter  
A codebook excited speech coder analyzes speech to produce coefficients of a synthesis filter, the parameters of a long-term prediction filter (LTP) and a codeword indication one of a set of...
6014621 Synthesis of speech signals in the absence of coded parameters  
A speech compression system called "Transform Predictive Coding", or TPC, provides for encoding 7 kHz wideband speech (16 kHz sampling) at a target bit-rate range of 16 to 32 kb/s (1 to 2...
6014623 Method of encoding synthetic speech  
A method of synthetic speech, wherein the method forms a speech data base, the speech data base includes plural syllables, each of the syllables having a total frame number of the syllable and...
6012024 Method and apparatus in coding digital information  
A speech encoder (100) receives speech signals (S) which are encoded and transmitted on a communication channel (120). Silence in the speech is utilized by a data encoder (101) to transmit data on...
6006177 Apparatus for transmitting synthesized speech with high quality at a low bit rate  
The invention provides a speech coding apparatus wherein a perceptual weighting filter is realized with a comparatively small amount of calculation. The speech coding apparatus includes a weighting...
6003001 Speech encoding method and apparatus  
In encoding in which an adaptive codebook such as PSI-CELP or a fixed codebook is used on switching selection, waveform distortion caused by selection of the fixed codebook in case input speech...
6003000 Method and system for speech processing with greatly reduced harmonic and intermodulation distortion  
A method and system for representing speech with greatly reduced harmonic and intermodulation distortion using a fixed interval scale, known as Tru-Scale. Speech is reproduced in accordance with a...
5999897 Method and apparatus for pitch estimation using perception based analysis by synthesis  
The present invention provides a method for pitch estimation which utilizes perception based analysis by synthesis for improved pitch estimation over a variety of input speech conditions....
5987406 Instability eradication for analysis-by-synthesis speech codecs  
Instability inherent in analysis-by-synthesis speech/audio codecs and caused in particular by channel errors during transmission of highly periodic signals such as high-frequency sine waves is...
5987405 Speech compression by speech recognition  
A method of transmitting speech signals with reduced bandwith requirements. With this invention an original speech signal is first converted to a textual representation, and a facsimile of the...
5983175 Audio coding method  
Coding of a high efficiency is achieved without increasing the scale of a code train transform table. Quantization spectra are divided into groups, and when two quantization spectra in any group...
5974376 Method for transmitting multiresolution audio signals in a radio frequency communication system as determined upon request by the code-rate selector  
The present invention relates to a method for transmitting multiresolution audio signals via wireless devices in a radio frequency communication system wherein audio signals are decomposed into...
5974377 Analysis-by-synthesis speech coding method with open-loop and closed-loop search of a long-term prediction delay  
A method comprising the steps of performing a linear prediction analysis of a speech signal digitized in a series of frames divided into sub-frames, in order to determine the parameters of a...
5963897 Apparatus and method for hybrid excited linear prediction speech encoding  
A method is given of encoding a speech signal using analysis-by-synthesis to perform a flexible selection of the excitation waveforms in combination with an efficient bit allocation. This approach...
5956686 Audio signal coding/decoding method  
An adaptive transform coding/and decoding arrangement is provided to effectively exploit different redundancies between the bands of a spectrum envelope to effect coding at a low bit rate for an...
5956672 Wide-band speech spectral quantizer  
A band splitter 3 makes predetermined frequency band splitting and computes each sub-band spectral coefficient for the cut out speech signal. Analyzers 5 and 7 each compute a spectral coefficient...
5946651 Speech synthesizer employing post-processing for enhancing the quality of the synthesized speech  
A post-processor 317 and method substantially for enhancing synthesised speech is disclosed. The post-processor 317 operates on a signal ex(n) derived from an excitation generator 211 typically...
5937376 Method of coding an excitation pulse parameter sequence  
The excitation pulse parameters are encoded when determining the positions of a given number of excitation pulses within a speech frame in a linear predictive speech encoder. The positions are...
5926788 Method and apparatus for reproducing speech signals and method for transmitting same  
An encoding unit 2 divides speech signals provided to an input terminal 10 into frames and encodes the divided signals on the frame basis to output encoding parameters such as line spectral pair...
5924062 ACLEP codec with modified autocorrelation matrix storage and search  
A codebook correlation matrix comprises a Toeplitz-type (diagonally symmetric) matrix which is calculated from a forty sample subframe of a speech signal, forming a 40×40 matrix. The resulting...
5924063 Celp-type speech encoder having an improved long-term predictor  
A speech signal encoder includes a speech analyzer for determining short-term prediction codes at a predetermined time interval. The prediction codes indicate frequency characteristics of a speech...
5909663 Speech decoding method and apparatus for selecting random noise codevectors as excitation signals for an unvoiced speech frame  
If the same parameter is repeatedly used in an unvoiced frame inherently devoid of pitch, there is produced a pitch of the frame length period, thus producing an extraneous feeling. This can be...
5905970 Speech coding device for estimating an error of power envelopes of synthetic and input speech signals  
In a speech coding device for coding an input speech with an AbS (Analysis by Synthesis) system and one of a forward type and a backward type configuration, a vocal tract prediction coefficient...
5899968 Speech coding method using synthesis analysis using iterative calculation of excitation weights  
A linear prediction analysis is performed for each frame of a speech signal to determine the coefficients of a short-Term synthesis filter. For each sub-frame, an excitations sequence which, when...
5893061 Method of synthesizing a block of a speech signal in a celp-type coder  
A new scheme to generate the stochastic excitation for a CELP-type speech codec based upon a hybrid stochastic codebook search technique including use of regular pulse excitation codebooks is...
5886276 System and method for multiresolution scalable audio signal encoding  
An audio signal analyzer and encoder is based on a model that considers audio signals to be composed of deterministic or sinusoidal components, transient components representing the onset of notes...
5884251 Voice coding and decoding method and device therefor  
In a voice coding and decoding method and apparatus using an RCELP technique, a CELP-series decoder can be obtained at a low transmission rate. A voice spectrum is extracted by performing a...
5884252 Method of and apparatus for coding speech signal  
In a speech coding apparatus, a spectral parameter calculator determines spectral parameters from an inputted speech signal, quantizes the spectral parameters, and outputs a plurality of...
5878388 Voice analysis-synthesis method using noise having diffusion which varies with frequency band to modify predicted phases of transmitted pitch data blocks  
A high efficiency encoding method for encoding data on frequency axis obtained by dividing an input audio signal on block-by-block basis and converting the signal onto the frequency axis, wherein V...
5875424 Encoding system and decoding system for audio signals including pulse quantization  
An encoding system is disclosed, which includes an input terminal for receiving an input signal, a signal converting portion for converting the input signal into frequency-domain signals and...
5875423 Method for selecting noise codebook vectors in a variable rate speech coder and decoder  
In a variable rate speech coding method for a CELP speech coding system, an adaptive sound source vector and a first noise source vector are selected from a sound source code book and a noise...
5873060 Signal coder for wide-band signals  
Wide-band speech signals and also music signals are coded with relatively less computational efforts and less sound quality deterioration even at low bit rates. A spectral parameter calculator...
5864650 Speech encoding method and apparatus using tree-structure delta code book  
A larger number, L', of delta vectors Δ i (i=0, 1, 2, . . . , L'-1) than the required number L are each multiplied by a matrix of a linear predictive synthesis filter (3), their power (AΔ i ) T ...
5864797 Pitch-synchronous speech coding by applying multiple analysis to select and align a plurality of types of code vectors  
A speech coder using a pitch synchronous innovation code excited linear prediction (PSI-CELP) speech coding system. The speech coder is capable of representing a portion which is not sufficiently...
5854814 Digital transmission system with improved decoder in the receiver  
A digital transmission system, such as a mobile radio system, having a transmitter for transmitting codewords which are derived from a digital signal, and a receiver for receiving codewords, the...
5848387 Perceptual speech coding using prediction residuals, having harmonic magnitude codebook for voiced and waveform codebook for unvoiced frames  
A speech encoding method and apparatus for encoding an input speech signal on a block-by-block or frame-by-frame basis wherein short-term prediction residuals are found and then sinusoidal analytic...
5839100 Lossless and loss-limited compression of sampled data signals  
An efficient method for compressing audio and other sampled data signals without loss, or with a controlled amount of loss, is described. The compression apparatus contains a subset selector, an...
5839098 Speech coder methods and systems  
Coding systems that provide a perceptually improved approximation of the short-term characteristics of speech signals compared to typical coding techniques such as linear predictive analysis while...
5828811 Speech signal coding system wherein non-periodic component feedback to periodic excitation signal source is adaptively reduced  
Speech coding uses a periodic excitation signal source, a non-periodic signal excitation source, a synthesizing unit, a filter, and an error evaluating unit. The synthesizing unit synthesizes a...
5828996 Apparatus and method for encoding/decoding a speech signal using adaptively changing codebook vectors  
An encoding apparatus in which an input speech signal is divided into blocks and encoded in units of blocks. The encoding apparatus includes an encoding unit for performing CELP encoding having a...
5826231 Method and device for vocal synthesis at variable speed  
A vocal synthesis method in which a speech signal is reconstituted by the selection from a dictionary of waveforms for the excitation of long-term and short-term predictive filters. To preserve, in...
5819212 Voice encoding method and apparatus using modified discrete cosine transform  
A method and apparatus for encoding an input signal, such as a broad-range speech signal, in which a number of decoding operations with different bit rates are enabled for assuring a high encoding...
Matches 201 - 250 out of 344 < 1 2 3 4 5 6 7 >