Software Implement Of Video Module In Videophone Based On PC

The digital revolution in the region of IT have changed the people's manner of life and work, and made the communication, computer and the public communication -the three major information operation overlapped. Further more, there is a characteristic of well-rounded appeared in the telecom transaction, except for the traditional voice transaction, the data transmission has became the main part of the telecom transaction. The traditional telephone just uses the transmission of the voice, but when people intercourses with language, he also hopes to speak face to face. So all these make the videophone appeared. But since the noun of videophone appeared, the videophone has not used broadly. The ITU has brought out a serial of recommendation for the videophone, but the video part of the videophone is the most difficult question puzzled all the technicians of the world.The paper aims at the most important part-the video compression theory and technique to discuss. First, the paper introduces the importance and the feasibility of the video compression, and introduces the history and development of the video compression. Then, the paper discusses the main and ripe means of the video compression since the technique appeared, and introduces the most effective and ripest mixed coding technique. Aims at the main recommendation H.263, the third part of paper discusses particularly. The paper introduces the technique of the recommendation on the basic frame, encoder and decoder's main technique and regulation, the syntax and semantics of the bitstream, optional coding algorithm, and etc. In the forth part of the paper, aimed the time-costest and most important technique-Discrete Cosine Transform (DCT) and Motion Estimate algorithms, paper analyses the classical and practical algorithms and introduce the theory. Then paper sum up all the algorithms character, give out the ameliorated algorithm, and simulate with the C language on the computer. These two algorithm, can be realized using hardware and can be used into the realvideophone's video module.But the paper has not studied the other parts of the compression recommendation detailedly, especially the optional mode can improve the videophone mostly, which wait for the further research and works.