Audio bandwidth extension coding and decoding method and device based on deep neutral network

Abstract

The invention discloses an audio bandwidth extension coding and decoding method and device based on a deep neutral network. The device includes a coding unit and a decoding unit. The coding unit includes an envelope preprocessor module, a high-frequency parameter extraction module, a low-frequency coding module and a code stream generation module. The decoding unit includes a code stream input module, a high-frequency parameter decoding module, a low-frequency signal decoding module, an auto-encoder parameter prediction module, a deep neutral network fine structure prediction module, a high-frequency signal reconstruction module, and a signal synthesis module. A fine structure of a high-frequency portion is predicated through autocorrelation between a signal low-frequency portion and a signal high-frequency portion by using a deep neutral network prediction method; then, the fine structure and edge information, obtained by a coding end, of the high-frequency portion are combined, and the signal high-frequency portion is reconstructed; and finally, the signal low-frequency portion and the signal high-frequency portion are fused, and a final recovery signal is obtained. Compared with a conventional method, the method has the advantages that the code rate is greatly reduced, and the tone quality is equivalent to that of the conventional method.

Description

Technical field [0001] The invention belongs to the technical field of audio coding, and in particular relates to an audio bandwidth expansion coding and decoding method and device based on a deep neural network. Background technique [0002] As people's requirements for sound quality increase and the number of mobile terminal users continues to increase, the requirements for audio coding efficiency are also increasing. Compared with the existing audio coding methods, the audio bandwidth extension technology has the advantages of high efficiency and low bit rate. The main idea is to use the correlation between the low frequency part and the high frequency part of the signal to encode the high frequency, in order to improve the sound quality and reduce the coding rate. The traditional audio bandwidth expansion extracts high-frequency parameters at the encoding end and transmits them to the decoding end. The decoding end copies the decoded low-frequency signal to the high-frequenc...

AI Technical Summary

Problems solved by technology

Aiming at the problem of poor coding quality caused by weak correlation between high and low frequency signals in the traditional method, the present invention provides an audio bandwidth extension coding and decoding method and device based on a deep neural network, and uses a multi-layer neural network to predict the high frequency part of the signal , to reduce the amount of data to be encoded in the high-frequency part of the signal to obtain better transmission efficiency

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