Predictive coding is a unifying framework for understanding redundancy reduction and efficient coding in the nervous system. By transmitting only the unpredicted portions of an incoming sensory signal, predictive coding allows the nervous system to reduce redundancy and make full use of the limited dynamic range of neurons. Starting with the hypothesis of efficient coding as a design principle ...

This paper concerns the intraframe coding of pictures. Conventionally the predictive coding methods use a two dimensional linear predictor which is based on the autoregressive model of the picture. This paper proposes two versions of a twodimensional lattice algorithm for linear prediction. This algorithm is arrived at by representing the forward prediction error as a function of a lower order ...

In this paper, we present a novel method to extract noise-robust speech feature representation in speech recognition. This method employs the algorithm of linear predictive coding (LPC) on the feature time series of mel-frequency cepstral coefficients (MFCC). The resulting linear predictive version of the feature time 國立暨南國際大學電機工程學系 Department of Electrical Engineering, National Chi Nan Univers...

Speech Coding is pivotal in the ability of networks to support multimedia services. The technique currently used for speech coding is Linear Prediction. It models the throat as an all-pole filter i.e. using a linear difference equation. However, the physical nature of the throat is itself a clue to its nonlinear nature. Developing a nonlinear model is difficult as in the solution of nonlinear e...

Randomness observed in human speech signals is considered to be a key factor in the naturalness of human speech. This research project has investigated the characteristics of several kinds of randomness observed in human speech signals phonated by normal speakers. Based on the results of the analysis, some advanced techniques for artificially reproducing such randomness were developed with the ...

In mobile communication systems, bandwidth is a precious commodity, and service providers are continuously faced with the challenge of accommodating more users within a limited allocated bandwidth. Linear Predictive Coding (LPC) offers low bit-rate speech coding that can be used to meet this challenge. The lower the bit rate at which the coder can deliver toll quality speech, the more speech ch...

Advances in speech coding technologies have enabled speech coders to achieve bit-rate reductions at a great extent while maintaining roughly the same speech quality. One of the most important driving forces behind this feat is the analysis-by-synthesis paradigm. Code Excited Linear Predictive coder (CELP) is the quite efficient closed loop analysis-by-synthesis method for narrow and medium band...

A novel variable rate linear predictive coding (LPC) parameter quantization scheme is proposed in which linear prediction is done by using either the current (forward LPC) or previously decoded (backward LPC) speech blocks. The proposed LPC quantization scheme was integrated into the FS1016 Federal Standard CELP coder. Signi cant LPC bit rate reduction is achieved without compromising the decod...

A highly e cient algorithm termed adaptive forward-backward vector quantization (AFBVQ) is developed for variable bit rate quantization of linear predictive coding (LPC) coe cients and integrated with the FS1016 Federal Standard Code Excited Linear Predictive (CELP) coder. This results in a high performance low bit rate speech coder called as AFBVQ-CELP which brings in two-fold bit rate reducti...

In this paper, we investigate several algorithms that construct the input for the synthesis filter in the CELP coder, we present them under the same formalism, and we compare their performances. We model the excitation vector by a linear combination of K signals, which are issued from K codebooks and multiplied by K associated gains. We demonstrate that this generalized form incorporates severa...