Echo canceling implementing method supporting a plurality of voice coding systems

Abstract

The invention discloses an echo canceling implementing method supporting a plurality of voice coding systems. The method is able to perform echo canceling processing for the voice under PCM (Pulse Code Modulation), CVSD (continuous variable slope delta modulation), G729 and AHELP voice coding systems; signals are shaped by the delay jitter buffer smoothing system to remove network delay jitter; the sampling rate and the gain are matched to adapt to mutual operation and conversion of different coding modes; the near end signal detection signal is treated as the basis for determining whether to update coefficients and parameters of an adaptive filter; the coefficients and parameters of the adaptive filter are updated according to the principle of minimizing the predication error signal mean square value, so as to improve the echo canceling processing precision.

Description

technical field [0001] The invention relates to the field of speech processing, in particular to the echo cancellation processing for multi-channel and different speech coding systems. Background technique [0002] In the process of voice communication, there are different degrees of delay in the network, and you can hear your own echo at the calling end, which will affect the quality of the call. In the PCM mode, an echo cancellation dedicated chip is used to complete the echo cancellation process, and the voice code conversion and echo cancellation are completed in different hardware functional entities, which increases the hardware design cost. The transcoding loss is introduced, which reduces the signal processing efficiency. Contents of the invention [0003] The present invention proposes a kind of echo cancellation for PCM (Pulse Code Modulation), CVSD (Continuously Variable Slope Delta Modulation), G729 (ITU-T G729), AHELP (Advanced Hybrid Excitation Linear Predic...

AI Technical Summary

Problems solved by technology

[0002] In the process of voice communication, there are different degrees of delay in the network, and you can hear your own echo at the calling end, which will affect the quality of the call. In the PCM mode, an echo cancellation dedicated chip is used to complete the echo cancellation process, and the voice code conversion and echo cancellation are completed in different hardware functional entities, which increases the hardware design cost. Introduces encoding conversion loss and reduces signal processing efficiency