UWB extension coding, decoding method, codec and UWB extension system

Abstract

A super-wideband extending coding and decoding method, coder and super-wideband extending system are provided. The coding method includes separating the super-wideband speech signal into high frequency sub-band signal and low frequency sub-band signal (101); speech decoding the low frequency signal parameter obtained by speech coding the low frequency sub-band signal to obtain the low band recover signal; time-frequency domain transforming and band extending the low band recover signal respectively to obtain the low frequency domain recover coefficient, the residual frequency domain coefficient and the residual frequency domain coding coefficient; perception weighting the low frequency domain recover coefficient and the residual frequency domain coefficient  based on the low frequency sub-band signal to obtain the model frequency domain coefficient, and spectral folding and time-frequency transforming the high frequency sub-band signal to obtain the high frequency domain coefficient, and matching the model frequency domain coefficient and the high frequency domain coefficient according to the Minimum Mean Square Error rule to obtain the frequency band extended parameter; transmitting the low frequency signal parameter, the residual frequency domain coding coefficient and coded extended parameter(109).

Description

technical field [0001] The invention relates to voice communication technology, in particular to an ultra-wideband extension encoding and decoding method, a codec and an ultra-wideband extension system. Background technique [0002] In real-time voice communication, because the transmission quality of voice signals is affected by factors such as sampling rate and bandwidth, existing voice and audio codecs usually use methods such as reducing the sampling rate and losing high-frequency content to ensure the codec process. realization. This is especially true for the transmission of wideband voice signals (50Hz ~ 7kHz). In order to avoid aliasing effects, the wideband signal is usually converted into a band-limited signal and then encoded. In this way, when the code rate is determined, especially for Medium and low bit rates, ensuring enough bits to encode low-frequency content. However, the high-frequency part of the broadband signal contains rich content, and the lack of t...

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Problems solved by technology

[0004] In the process of realizing the present invention, the inventor found that the prior art has at least the following problems: the prior art extends the narrowband voice signal from 0 to 3.4kHz to 0 to 7kHz, and only completes the frequency band extension of less than 4kHz, and the decoded The voice signal lacks ultra-wideband signals above 7kHz, so that the audio quality still cannot be greatly improved; the excitation signal used in the frequency band extension is derived from the speech generation model, which cannot accurately describe the music signal, and the coding effect for the music-like signal is relatively poor , the reuse effect is not good in the ultra-broadband part

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