Development Of The Vehicular Multimedia Speech Commands Control System

With the development of modern automobile industry and embedded technology,vehicle multimedia system has been popular among our life.As operation mode of vehicular equipments should be more convenience and more security,voice commands, a natural and rapid interactive way, has become the first choice.Practical research is a new direction in speech recognition field,so application of speech recognition technology to vehicular system will improve the applications and popularization of vehicular devices greatly.The article is dedicated to study the development of vehicular speech command control system.As the problems of limited storage and high real-time in embedded system, the study work of the paper mainly on algorithm optimization of speech recognition and construction of vehicular speech command control system.(1) Aiming at the large amout data of speech feature vector sequence after the traditional MFCC, Vector Quantization technique is adopted to optimize data quantity.The experimental results show that the method reduces the data storage by 91%.(2) Aiming at more than one to operate the vehicular speech command control system, DHMM algorithm is adopted to identify non-specific human voice command control. Meanwhile training module of HMM is finished in PC for more rational use of embedded resource.(3) The paper studies the software platform of the vehicular speech command control system. It mainly include construction of embedded software development environment、design of bootloader in Linux、detailed processing of clipping and complie-transplant for kernel、clipping-transplant for audio driver and creating of a root filesystem etc.The article also explains characteristics of the Qt/Embedded graphical interface development platform and construction of cross development environment. Finally, the text transplants Linux software platforms to ARM9 development board and construct vehicular speech command control system successfully.(4) Vehicular speech command control system is realized in ARM9 development platform based on embedded software platform constructed. The operator inputs voice commands by MIC and then the vehicle-mounted system completes the corresponding instruction operation according to the identify result. Test results show that both identification accuracy and real-time of the system meet the practical needs of vehicle-mounted multimedia for automobile.