The Research Of G.729 Speech Codec Algorithm And On The Implement On S3C2440

With the development of economy and the advent of the informationage, the theme of multimedia communications information network has become the focus of attention of the world. The success of IP video phone development and application foretells IP-based next-generation information advent of the Internet. As for the standardization of communications urgent requirement ,the speech coding standardization made a lot of progress, and future research directions will be gradually shifted to a lower rate. g.729 coding is the method of LPC encoding and its'data rate of 8 kbit / s, has been widely used on VOIP, video conference systems.Digital voice signal transmission, has been one of the direction of development communication. Use low-bit-rate speech coding technology for voice transmission has more advantages than analog voice signal transmission, the development trend of modern communications decision voice coding technology of the two outstanding advantages, first, saving bandwidth, and the second is easy to realize and IP integration. G.729 is an 8 kbps Conjugate-Structure Algebraic-Code-Excited Linear Prediction (CS-ACELP) speech compression algorithm approved by ITU-T.Its appearance,has great significance for People efficient use of IP networks.In this paper, we firstly make an introduction of the speech coding technology development and classification, next make a brief statement on the basic principles of G.729, in view of the ITU-T algorithm source code, use of a VC + + 6.0 software simulation, and the G.729 algorithm has been optimized. Hardware platform is based on Samsung's S3C2440A, use AD1885 analog input speech signal into a digital signal which is collected by Mike, the digital signal controller AC97 audio link control (AC-LINK) into the ARM chip encoded S3C2440A and then sent CPU decode. Software platform is based on ARM debugging development environment ADS1.2 to complete the preparation of the application procedures, debug and download, thus S3C2440A achieved G.729 the original speech signal codec. G.729 has been widely used DSVD, digital satellite system, video conferencing,video telephony,IPtelephonyand mltimedia communication systems, has good prospects.