CAJ | 학술논문

由于G.729A运算模块中开环基音搜索占据了比较大的运算量，在分析了它的算法结构之后，提出了4：1的抽取方法，即对采样信号点及最佳延时搜索点进行4：1的抽取。同时，在C代码的基础上去除了串行化模块中1 bit向Word16的数据转换，避免了程序中语音数据的类型转换。最后，将优化后的G.729A封装成静态库，加载到iPhone语音通话软件中进行测试。结果显示，提出的方法降低了开环基音搜索的复杂度，在语音质量稍微有所下降的基础上，提高了语音实时性。
유우G.729A운산모괴중개배기음수색점거료비교대적운산량，재분석료타적산법결구지후，제출료4：1적추취방법，즉대채양신호점급최가연시수색점진행4：1적추취。동시，재C대마적기출상거제료천행화모괴중1 bit향Word16적수거전환，피면료정서중어음수거적류형전환。최후，장우화후적G.729A봉장성정태고，가재도iPhone어음통화연건중진행측시。결과현시，제출적방법강저료개배기음수색적복잡도，재어음질량초미유소하강적기출상，제고료어음실시성。
As the open-loop pitch search in the G. 729A computing module occupied a relatively large amount of com-putation,this paper analyzed its algorithm, and proposed a method that we extracted the speech signal and the optimum delay search by 4. Meanwhile. On the basis of C code,we removed the data conversion from 1bit to Word16 in serialized module to avoid type conversion of data in the program. Finally, G. 729A was packaged into a static library,and then loaded into the iPhone voice software for testing. The result showed that the proposed method did reduce the complexity of open-loop search and improve the real-time performance with low degradation in voice quality.