Signal coding and decoding method and device, and coding and decoding system

Abstract

The embodiment of the invention relates to a signal coding and decoding method and a device, and a coding and decoding system, wherein the signal coding method comprises the following steps: carrying out classification and judgment treatment on high-frequency band signals in input signals; carrying out self-adapting coding on the high-frequency band signals according to the results of the classification and judgment treatment; and outputting code streams including the codes of low-frequency band signals in the input signals, the self-adapting codes of the high-frequency band signals and the results of the classification and judgment treatment. The embodiment carries out the classification and judgment treatment on the high-frequency band signals, carries out the self-adapting coding or the self-adapting decoding on the results of the classification and judgment treatment, and improves the quality of audio-frequency output signals.

Description

technical field [0001] Embodiments of the present invention relate to the field of speech and audio encoding and decoding, and in particular, to a signal encoding and decoding method and device, and an encoding and decoding system. Background technique [0002] In the speech and audio coding algorithm, the low frequency band signal is usually encoded preferentially due to the limitation of the auditory characteristics of the human ear and the bit rate. With the development of the network, the restrictions on bandwidth are getting smaller and smaller, and people have higher requirements for sound quality; by increasing the signal bandwidth, the sound quality of the signal can be improved. When there are no bits or the number of bits is small, the bandwidth can be used. extended technology. As a technology to expand the frequency band range of voice signals and improve signal quality, bandwidth expansion technology has made great progress in recent years, and has been commerc...

AI Technical Summary

Problems solved by technology

[0003] Among the bandwidth extension technologies provided by the prior art, one is: at the encoding end, the high-frequency signal is not encoded, and the encoding algorithm of the low-frequency signal in the existing encoder is not changed. At the decoding end, according to the low-frequency The potential relationship between the band signal and the high and low frequencies, blindly expand the high band signal; in this method, since there is no relevant information of the high band signal at the decoding end for reference, the extended high band signal poor quality

[0004] The other is: at the encoding end, encode some time domain envelope and frequency domain envelope information of the high frequency band signal, at the decoding end, generate an excitation signal according to the spectrum information of the low frequency band signal, combine the excitation signal and the decoding The time-domain envelope and frequency-domain envelope information of the high-frequency band signal are obtained to restore the high-frequency band signal; compared with the above method, the quality of the high-frequency band signal extended by this method is better, but for some harmonics In terms of wave strength signals, this method is prone to large distortion, therefore, the quality of the voice and audio signals output by this method also needs to be improved

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