**1. Introduction**

82 Video Compression

Zhibo Chen, Jianfeng Xu, Yun He, Junli Zheng (2006) Fast integer-pel and fractional-pel

Vol.17,pp. 264–29,

motion estimation for H.264/AVC, *International Journal of Visual Communication*,

In this chapter, global motion estimation and its applications are given. Firstly we give the definitions of global motion and global motion estimation. Secondly, the parametric representations of global motion models are provided. Thirdly, global estimation approaches including pixel domain based global motion estimation, hierarchical global motion estimation, partial pixel set based global motion estimation, and compressed domain based global motion estimation are reviewed. Finally, four global motion based applications in video compression, sport video shot classification, video error concealment, and video text occluded region recovery are given.

Motion information is very important for video content analysis. In surveillance video, usually the camera is stationary, and the motions of the video frame are often caused by local motion objects. Thus detecting motions in the video sequences can be utilized in abnormal events detection. In sports video, the heavy motions are also related to highlights. Motion estimation and compensation is the core of video coding. Coding the residual component after motion compensated can save bit-rates significantly. In video sequences, the motion pattern can be classified into two types: local motion and global motion. The global motion is related to camera motion. Integrated with local motion, global motion is widely utilized in video object segmentation, video coding and error concealment. The rest of this chapter is organized as follows: the definition of global motion is given in Section 2. The global motion models are given in Section 3. Global motion estimation approaches are given in Section 4. Four applications based on global motion and local motion (GM/LM) information are introduced in Section 5. The applications are GM/LM based video coding, global view refinement for soccer video, GM/LM based error concealment and GM/LM based text occluded region recovery. And finally conclusions are drawn in Section 6.
