Multimedia Communication On Network--The Research Of Speech Coding Technology

With the development of LAN, Intranet and Internet and the improvement of IP network performance, the multimedia communication based on IP network has become an important research and development branch of the future communication system. As a basis of multimedia communication, speech coding becomes the focus of discussion. The G729A, a new issued speech compressed coding standard at 8kbit/s, is one of the optional coding standards of H.323, which is multimedia meeting system standard based on IP network.With a view to IP character and G729A coding arithmetic, a speech codec scheme in software is presented in this paper. With the DirectSound technology, an important part of DirectX 8.0, the capturing and playback of speech is achieved. The compressed encoding of speech is implemented with G729A coding arithmetic, together with some relative measures mentioned in the paper. The software module of coding and decoding are linked dynamically to improve the system processing efficiency.