High Magnification Of The Audio And Video Compression And Video Digital Watermark Technology

During the development of digital multimedia and the Internet, together with thedevelopment of streaming media technology, it is possible to enjoy the digital multimedia programs of high quality online. This online business is becoming more and more popular because there is plenty of resource in the Internet. However, there are many difficulties in developing the real-time streaming media application system, e.g. the limit of the system efficiency, the delay, jitter and loss of packets due to the isomeromorphism and variance of the network, and communication security. So we have designed a system which is adaptive to adjust the video data rate, using the efficient compression of audio/video, with checking the variance of the network's bandwidth while maintaining the integrality and synchronization of audio data. We have developed one data-streaming switch arithmetic for MPEG-4 bitstream which has the ability of changing the data-rate according to the network's bandwidth and has the advantage of real-time and low complexity. On the other hand, we have adopted the video digital watermarking technology to meet the need of the security communication. The video watermarking technology is the popularity and difficulty part of digital watermarking research field. The watermarking embedding arithmetic we chose is to embed the watermark at the chroma DCT field of the I-VOP frame and Motion Vectors in the MPEG-4 bitstream, based on the idea of spread spectrum. This watermarking arithmetic has the feature of low complexity, strong robustness and fit the security requirement of the real-time multimedia system.At the end of my paper, we do the testing like the real-time behavior of the system, the robustness of the watermarking and low bandwidth communication ability etc. And the test result show that the system has the excellent feature of real-time and security and is satisfy with practice application. And we do the software/hardware analysis and design of Ti-OMAP730 Mobile Multimedia Development Platform, in order to transplant our system to the mobile system on future.