Motion Video Object Segmentation And Data Rate Distribution And Control Technology

In modern society the requirement on information is becoming the main factor to promote the development of information technology. On the video information and its processing technology have been made much progress. Because of the enormous data, it is quite difficult to be saved and lively transported. And also be hindered the application of digital video information. So it is urgently required to take a research on the effective representation of video data and its encoding rate control. As the first generation of video encoding, MPEG-1 and MPEG-2 are both based on the blocks in frame and prediction between frames. Although they are greatly reduced the related redundancy, but have not use the content segmentation of VO(video object). With the development of the interactive multi-media applications in the multi-media communication and integrated network service, the second generation of video encoding comes into being with its representative of MPEG-4. The video scene is divided into a lot of regions with each region corresponding to a meaningful video object (VO) on syntax; and then the different encoding techniques can be adopted to different video objects according to their features. These encoding methods can greatly improve efficiency and the user can operate the video data according to the content. To the second generation of encoding it is necessary to make more analysis on the motion, texture, shape and information quantity of different video objects in images. As we know, the automatic creating and rate control of VO is the key point of encoding based on object and interactive operation while there are no concrete specifications on them in existing standards. Thus, the research on how to create VO and the rate control of multi-VO has become a pop subject. The motion object region is called as out-point in the global motion estimation. Because the local motion vector of out-point is participated in forming the global motion vector, the accuracy and complexity of global motion estimation will be influenced especially when the out-point region is a big part in images. So the elimination of out-point becomes significant for accurate global motion estimation. Usually out-point is eliminated by statistical method. The pre-analysis of video image based on the ratio of temporal gradients to spatial gradients is used in some papers to eliminate out-points, but its effect is not good. In our thesis, the pre-analysis based on block match of edge characteristic image is adopted according to its characteristic that out-points tend to gather into block in image. Through this way, the fairly big region of out-points can be eliminated and different models of global motion are used for the different images. Thus the accuracy of the estimation of global motion vector has been improved greatly. There are three kinds of techniques to estimate the global motion: techniques based on pixel level, visual features in spatial domain and visual features in transformation domain. In the view of the ability of anti-noise, adaptability and the accuracy of estimation, the techniques based on spatial visual features are the best in the three. In this thesis, the technique of global motion estimation with multi straight-line features is discussed. In this way, it is easy to estimate the parameters of global displacement and rotation with good accuracy and relatively simple algorithm. To extract moving object in the video sequences, the adjacent frame difference and optical flow methods are adopted extensively. Its main drawback is that the outline of the motion objects is hardly to be detected precisely. In this thesis, an improved algorithm of double differences in the adjacent triple frames has been raised. The region of motion can be extracted effectively with better adaptability and strong ability of anti-noise.After compensation of global motion, the difference image is composed of remainder noise region and motion changing region. Based on the date structure of image, the image has been divided into bit planes. The vi...