一种基于HTK的数字语音识别系统

摘要

数字语音识别是语音识别一个极其重要的分支,其在现实生活中的应用愈加广泛.HTK是英国剑桥大学开发的一套基于C语言的语音处理工具箱,广泛应用于语音识别、语音合成、字符识别和DNA排序等领域.从HTK的基本原理和软件结构出发,设计了一个基于HTK的数字语音识别系统,并验证了其识别效率.随后,通过更换识别单元,更改特征参数的维数和增加高斯混合分量的个数来考虑不同因素对系统性能的影响.最后,通过比较试验,验证了识别单元、高斯混合分量的数目以及MFCC维数的适当组合可提高系统的正确识别率.%Digital speech recognition is an extremely important branch of speech recognition. Its application in real life is used more and more widely. HTK is a C language-based toolkit developed by CUED mainly used for speech signal reorganization, speech synthesis, character reorganization, DNA compositor and so on. From HTK's general principles and software architecture, this paper designs a digital speech recognition system based on HTK, and verifies its recognition efficiency. Then by changing the identification unit and MFCC dimension, and by increasing the number of gaussian mixture components, it considers effects of different factors on the performance of the system. Finally, through the comparing test, it verifies the right combination of the identification unit and the number of gaussian mixture components, and also proves that MFCC dimension can enhance the system's correct rate.