Fundamental frequency contour extraction artificial cochlea speech processing method and system

Abstract

The invention discloses a fundamental frequency contour extraction artificial cochlea speech processing method and system. The method comprises the steps of: performing downsampling on a received frame of acoustical signals; performing first low pass filtering; performing first derivation, maintaining the periodicity and trend shape of signals and reducing signal amplitudes; reducing order difference, and determining a periodic point at a smallest difference absolute value through comparing the difference absolute value between an original signal and a time shifting signal; performing secondary low pass filtering, and smoothing signals, especially each bottom; searching for a smallest value and a second smallest value of a current frame, and voiding doubling or halving of a fundamental frequency; and comparing two continuous frames of smallest values to obtain a periodic change value delta T. The method and system solve the calibration problem in fixed-point calculation to the maximum, guarantee signal periodicity, and reduce a total amount of calculation; in addition, the method and system track a baseband signal envelop change rate instead of a fundamental frequency absolute value to minimize the total amount of calculation; meanwhile, the parameter selection for adjusting the change rate can be flexibly applied to an artificial cochlea strategy.

Description

technical field [0001] The invention belongs to the field of medical devices, and in particular relates to a cochlear implant speech processing method and system for extracting fundamental frequency contours. Background technique [0002] The fundamental frequency of speech plays an extremely important role in language understanding. In Chinese, the fundamental frequency plays a decisive role in distinguishing the four tones of Mandarin. Fundamental frequency is the essential component of Mandarin tones, and it is a sufficient and necessary sign to identify Mandarin tones. [0003] Fundamental frequency extraction is a fundamental problem in speech signal processing. In the past 40 years, people have proposed hundreds of fundamental frequency extraction algorithms. Different application scenarios determine the complexity and robustness of the algorithm. Fundamental frequency extraction algorithms applied to real-time signal processing have always been the focus of speech...

AI Technical Summary

Problems solved by technology

At present, there is no report on real-time extraction of fundamental frequency information on all commercial cochlear implant speech processors

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