Linear prediction speech coding method and speech synthesis method

Abstract

The invention discloses a linear prediction speech coding method and a speech synthesis method. The linear prediction speech coding method includes the following steps: speech is preprocessed; second-order backward linear prediction is carried out on the preprocessed speech, so that a residual signal is obtained; wavelet decomposition and compression are carried out on the residual signal, so that a wavelet coefficient is obtained, vector quantization is carried out on the wavelet coefficient, and meanwhile, the pitch period and gain parameters of the residual signal and the unvoicing and voicing characteristic of each sub-band are calculated and respectively and scalarly quantized. The speech synthesis method is based on the linear prediction speech coding method. After being adopted, the technical scheme of the invention can reduce the affection of noise on the quality of decoded speech, inhibit the deterioration of speech quality when unvoicing and voicing judgment is mistaken and improve the performance of coding unvoiced speech or background noise.

Description

technical field [0001] The invention relates to speech coding technology, in particular to a linear predictive speech coding method and a speech synthesis method. Background technique [0002] With the rapid development of information society and communication technology, frequency resources become more and more precious. In the field of digital mobile communication and voice storage, in order to effectively utilize the communication bandwidth or storage space, it has always been the goal pursued by people to use the voice coding device to compress the transmission bandwidth of the voice signal or reduce the transmission code rate of the telephone channel to improve the efficiency of coding. With the increase in the number of communication network users and the integration and diversification of network services, the contradiction between network bandwidth, system capacity and service quality has become increasingly prominent. Traditional voice compression coding technology ...

AI Technical Summary

Problems solved by technology

[0006] The speech quality of the existing vocoder based on linear prediction strongly depends on the noise intensity of the original speech. When the signal-to-noise ratio of the original speech is poor, the judgment error of unvoiced and voiced sound and the error of pitch extraction will lead to serious pitch distortion and make the synthetic naturalness decline

In these technologies, the pitch period, gain and subband unvoiced sound of the excitation signal are all extracted from the original speech. When the receiving end restores the excitation signal, some parameters come from the original speech, and some parameters come from the residual signal, so that the decoded speech quality restricted

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