Small Vocabulary Isolated Words Speech Recognition Method Research

The computer plays a more and more important role in the human’s life, the human expect to communicate with the computer not only just through the keyboard, but also hope to communicate with it in a more direct way to let the computer understand human’s nature language. Because of human’s that expectation, speech recognition gradually developed, It’s a multi-disciplinary emerging science, and it has a broad prospect of application. Along with the computer processing capacity and speech processing technology increasing quickly, speech recognition technology is also obtained the rapid development, the related research achievements are endless. more and more speech recognition products came into all aspects of human’s life, a lot of intelligent household products use the speech recognition function modules, provides convenient for human’s life.This thesis reviewed the speech recognition technology development history, analyzed the research status. a detailed study of the basic principle of a speech recognition and treatment process. Analysis of the speech signal preprocess, such as pre-emphasis, enframes, endpoint detection. and give out a detailed study of the endpoint detection, using the method of double threshold endpoint detection test out the experiment of speech endpoint and starting over endpoints. For voice signal feature extraction process, analyzes the LPC, LPCC and MFCC characteristic parameters extraction method, through the contrast analysis, found that, combined with an order difference and cepstrum after MFCC parameters of ascension than the other characteristic parameters, the rate and the noise performance has certain advantages, and can be used for voice recognition of the characteristic parameters. In the study of the method of speech recognition, DTW algorithm for analysis, and take out the simulation experiment of DTW algorithm, and then proposes an improved DTW algorithm, The algorithm is compared with the traditional DTW algorithm, reducing matching area, The experimental results show that the improved algorithm in does not affect the recognition rate of speech recognition system, can improve the system of significant recognition speed, to improve the real-time speech recognition system plays an important role. Finally the design based on the Specific person DTW isolated words speech recognition system, this system integration the recording, signal observation, preprocess, parameter analysis, specific person isolated words speech recognition, and other functions, and take out the system recognition rate and real time contest, the system recognize0to9these ten digitals has got a good performance. the results show that this system has a very good performance at the recognition rate and real time. and in the system for specific person with the non-specific person performance are analyzed, the result shows that this system for specific person speech recognition has better effect.