We present an MPEG slice layer model for VBR encoded video using linear predictive coding (LPC) and generalized periodic Markov chains. Each slice position within an MPEG frame is modeled using an LPC autoregressive f...
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We present an MPEG slice layer model for VBR encoded video using linear predictive coding (LPC) and generalized periodic Markov chains. Each slice position within an MPEG frame is modeled using an LPC autoregressive function. The selection of the particular LPC function is governed by a generalized periodic Markov chain; one chain is defined for each I, P, and B frame type. The model is sufficiently modular in that sequences which exclude B frames can eliminate the corresponding Markov chain. We show that the model matches the pseudo-periodic autocorrelation function quite well. We present simulation results of an asynchronous transfer mode (ATM) video transmitter using a FIFO queue and measure the average cell delay. Simulation results showed good agreement with results obtained using actual traces as sources.
A system capable of recognizing isolated speech utterances with a rate of 97% and rejection rate of 2% on a 200-wood vocabulary is presented. The system uses linear predictive coding and dynamic time warping, both imp...
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A system capable of recognizing isolated speech utterances with a rate of 97% and rejection rate of 2% on a 200-wood vocabulary is presented. The system uses linear predictive coding and dynamic time warping, both implemented in software on an Apple Macintosh computer. The Macintosh also provides an environment for a graphics human interface in the authors' speech research. The system is intended for vocal shaping of severely disabled individuals.< >
In the real-time speech recognition, the predictor coefficients of speech signals are used as the recognizing features and should be computed faster than the sampling rate. Under such performance constraint, the objec...
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ISBN:
(纸本)0818628456
In the real-time speech recognition, the predictor coefficients of speech signals are used as the recognizing features and should be computed faster than the sampling rate. Under such performance constraint, the objective is to design this circuit as cheap as possible. Autocorrelation method is adopted for computing the coefficients because of its stability of the results and regular computations. A two-step pipelined functional unit is designed for calculating those regular computations. For the divisions needed in autocorrelation method, the prune-and-search approach is used to compute them. Because this approach can also be performed by the identical pipelined functional unit, the extra operator for the divisions is not required. Although the authors have designed this chip with least storage element and functional unit, however, the performance is still much faster than the real-time request.< >
Recent work has shown that multi-band excitation (MBE) is capable of synthesizing high quality speech in the range of 4.8-8.0 kbps. In this paper, the multi-band excitation and linear predictive coding (MBE-LPC) model...
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Recent work has shown that multi-band excitation (MBE) is capable of synthesizing high quality speech in the range of 4.8-8.0 kbps. In this paper, the multi-band excitation and linear predictive coding (MBE-LPC) model, which used the LPC analysis to obtain the prediction residual, and uses the MBE model to estimate the residual spectrum is presented. Our motivation is to improve the excitation model of LPC vocoders in the frequency domain. Based on the MBE-LPC model, a 5.4 kbps speech coding is presented. An adaptive postfilter is used to improve the perceptual quality of the decoded speech. Informal listening tests show that the perceptual quality of the decoded speech of the proposed coder is better than that of the 4.15 kbps improved (IMBE) coder.< >
An advanced spectral encoding method used in combination with independent component analysis (ICA) yields promising results in identifying refinery fractions contained in commercial gasoline mixtures based on infrared...
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An advanced spectral encoding method used in combination with independent component analysis (ICA) yields promising results in identifying refinery fractions contained in commercial gasoline mixtures based on infrared (IR) spectroscopy data. Previous work has shown how the signatures of the gasoline constituents can be recovered by solely relying on the IR spectra of their mixtures using ICA as a blind separation procedure. The present methodology encodes peak information from the spectra in linearpredictive (LP) coefficients which are subsequently transformed into line spectrum frequencies (LSF). Such encoded spectra have a drastically reduced size (to 1/20 of the original size) while preserving the crucial peak information that characterizes each constituent. Source identification is then established by simply computing a Euclidean distance measure between the corresponding LSF of the gasoline constituents predicted by ICA and the LSF available from the spectral library of candidate matches. High correlation scores are associated with successful identification of source spectra, and this indicates that the present methodology can be employed as an effective tool in fingerprinting applications. (c) 2007 Elsevier B.V. All rights reserved.
In today's world, telecommunication is the field in which the maximum research work is being done and speech compression is the most vital part of communication. For high compression rate speech coders, voice exci...
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In today's world, telecommunication is the field in which the maximum research work is being done and speech compression is the most vital part of communication. For high compression rate speech coders, voice excited linear predictive coding (VELP) is most widely used. This paper presents real time analysis of VELP by implementing it on TMS320C6711 DSP kit using Simulink RTW (real time workshop) which explains simulink model of VELP, VELP analysis, VELP synthesis, VELP implementation on DSP kit. VELP can be briefly explained as the signal is passed through analyzer, which generate the filter co-efficients and residual signal. The residual error signal has less redundancy than original speech signal and can be quantized by smaller number of bits than the original speech. The residual error signal along with the filter coefficients are transmitted to the receiver. At the receiver, the speech is reconstructed by passing the residual error signal through the synthesis filter. To model a human speech production system, all-pole model (also known as the linear prediction model) is used. For the real time analysis of VELP, it is implemented on DSP kit using MATLAB Simulink model
A reliable scheme based on a linear predictive coding algorithm (LPCA) is proposed for monitoring in real-time the status of the control system under both steady and transient states. An ARMA model of the error signal...
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A reliable scheme based on a linear predictive coding algorithm (LPCA) is proposed for monitoring in real-time the status of the control system under both steady and transient states. An ARMA model of the error signal of the closed-loop control system is estimated using LPCA. In the transient state, using the ARMA coefficients, integral squared-error and pole-location-based unit step response measures and stability robustness using Kharitonov's theorem are computed, and a fault is predicted. In the steady state, a deviation from the nominal model is detected from the ARMA-based power spectral estimates. The monitor displays information in decreasing order of importance and with increasing amounts of computation such that the essentials are known in the shortest possible time, with complete details emerging later. The proposed scheme is evaluated on a simulated complex multivariable control system.< >
In this paper, we derived a relationship between linear predictive coding (LPC) coefficients and Immittance Spectral Pairs (ISP) pseudo-cepstrum. In Adaptive Multi-Rate Wideband (AMR-WB) speech codec, ISP parameters w...
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ISBN:
(纸本)9781424446995
In this paper, we derived a relationship between linear predictive coding (LPC) coefficients and Immittance Spectral Pairs (ISP) pseudo-cepstrum. In Adaptive Multi-Rate Wideband (AMR-WB) speech codec, ISP parameters were used for quantisation and interpolation. This paper first described the representation of ISP pseudo-cepstrum. ISP pseudo-cepstrum was defined as the inverse z-transform of half natural logarithm of immittance function. References [2] and [3] proposed two kinds of new perceptual weighting filters based on ISP pseudo-cepstrum. Spectral tilt is more pronounced in wideband signals due to the wide dynamic range between low and high frequencies. The proposed filters are helpful for solving this problem. Then we gave the conversion method between ISP pseudo-cepstrum and polynomials cepstrum coefficients. Finally we derived the recursive relations between ISP pseudo-cepstrum and LPC coefficients. There are two methods of converting LPC coefficients to ISP pseudo-cepstrum. The one is directly from LPC coefficients to ISP pseudo-cepstrum. The other is from ISP parameters.
In this paper, the improved linear predictive coding (LPC) coefficients of the frame are employed in the feature extraction method. In the proposed speech recognition system, the static LPC coefficients + dynamic LPC ...
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ISBN:
(纸本)0780381858
In this paper, the improved linear predictive coding (LPC) coefficients of the frame are employed in the feature extraction method. In the proposed speech recognition system, the static LPC coefficients + dynamic LPC coefficients of the frame were employed as a basic feature. The framework of linear discriminant analysis (LDA) is used to derive an efficient and reduced-dimension speech parametric speech vector space for the speech recognition system. Using the continuous hidden Markov model (HMM) as the speech recognition model, the speech recognition system was successfully constructed. Experiments are performed on the isolated-word speech recognition task. It is found that the improved LPC feature extraction method is quite efficient.
The control system status features are extracted by using fast recursive least-squares lattice (RLSL) and block linear predictive coding algorithm (LPCA), respectively. A short time record of control system signal is ...
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The control system status features are extracted by using fast recursive least-squares lattice (RLSL) and block linear predictive coding algorithm (LPCA), respectively. A short time record of control system signal is captured and the future trend of the system is predicted by analyzing the variations of the estimated auto regressive and moving average (ARMA) model parameters. The comparison of two methods applied in system performance monitoring with real-time data cases are given and their performance are evaluated.
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