Voice signal bandwidth expansion method and device thereof

Abstract

The invention discloses a voice signal bandwidth expansion method and a device thereof. The method comprises the following steps: (1) carrying out sampling rate conversion processing on a voice signal and obtaining a high frequency signal and a low frequency signal after filtering, (2) estimating high frequency signal energy and obtaining a high frequency signal energy value, (3) when the high frequency signal energy value is larger than a preset energy threshold, judging the voice signal as a broadband voice signal, carrying out gain or attenuation adjustment on the high frequency signal, and overlapping the low frequency signal with the adjusted high frequency signal for outputting, (4) when the high frequency signal energy value is smaller than or equal to a preset energy threshold, judging the voice signal as a narrowband voice signal, carrying out bandwidth expansion on the low frequency signal, obtaining a bandwidth expansion high frequency component, and overlapping the low frequency signal with the bandwidth expansion high frequency component for outputting. According to the method and the device, the bandwidth expansion processing mode is adjusted adaptively, the bandwidth expansion processing is carried out on the narrowband voice signal, the voice quality is improved, the broadband voice signal is outputted directly, the wrong expansion of the broadband voice signal is avoided, and the voice quality is ensured further.

Description

technical field [0001] The invention relates to the technical field of signal processing, in particular to a method and a device for expanding the bandwidth of a voice signal. Background technique [0002] The frequency bandwidth of human speech signals is mainly distributed between 50Hz and 8kHz, but in the process of speech communication transmission, due to the limitation of analog signal transmission, the speech bandwidth is limited between 300Hz and 3400Hz, which is called narrowband speech signal. Due to the lack of high-frequency information in narrowband speech signals, the clarity of speech is affected to a certain extent. With the continuous development of voice communication technology, broadband voice communication terminals appear, which can support broadband voice signals in the frequency range of 50Hz~7000Hz, and can output better call quality. However, because traditional narrowband voice signals still dominate, the current communication network is a voice c...

AI Technical Summary

Problems solved by technology

However, if the broadband voice communication terminal receives an input broadband voice signal, the terminal cannot perform adaptive processing according to the signal characteristics, and will still perform voice bandwidth expansion processing on the wideband voice signal, and the high-frequency information obtained by artificially expanding the bandwidth is more fidelity Impossible to outperform the original signal, wasting computing power and degrading speech quality

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