Coarse-to-fine moving region segmentation in compressed video

In this paper, we propose a coarse-to-fine segmentation method for extracting moving regions from compressed video. First, motion vectors are clustered to provide a coarse segmentation of moving regions at block level. Second, boundaries between moving regions are identified, and finally, a fine segmentation is performed within boundary regions using edge and color information. Experimental results show that the proposed method can segment moving regions fairly accurately, with sensitivity of 85% or higher, and specificity of over 95%.