Abstract.
The main purpose of this paper is to present a software application for audio and video data acquisition and exchange that run in a heterogeneous teleconferencing system. Also, the paper wants to prove that a teleconferencing system can run with good performance on cheaper platforms like PCs and that this type of application has many possibilities of development. The paper treats, in detail, the problems that we encountered in the implementation of a PC client application for a teleconferencing system running on a Sun platform. The application was developed for PCs using Visual C++ 4.0 and its Microsoft Foundation Classes under Windows 95 and it was tested on both Windows 95 and Windows NT operating systems. The hardware as well as software aspects are discussed in order to emphasize their influence on the overall performances of the application. A detailed description of the solution chosen for audio and video data acquisition and exchange is given. The characteristics of the transport and network protocol used for data exchange are described. Another problem discussed is related to the compression and decompression of video data. A short description of an implementation of an on-line JPEG decompressor is given. Finally, the performances and the future directions for the development of the application are presented.

Keywords: multimedia, audio and video data streams, video decompression, AVICap window class, callback functions, JPEG.