Dynamic programming framework for automatic video object segmentation and vision-assisted video pre-processing
A generic definition of video objects, which is a group of pixels with temporal motion coherence, is considered. The generic video object (GVO) is the superset of the conventional video objects considered in the object segmentation literature. Because of its motion coherence, the GVO can be easily recognised by the human visual system. However, due to its arbitrary spatial distribution, the GVO cannot be easily detected by the existing algorithms which often assume the spatial homogeneousness of the video objects. The concept of extended optical flow is introduced and a dynamic programming framework for the GVO detection and segmentation is developed, whose solution is given by the Viterbi algorithm. Using this dynamic programming formulation, the proposed object detection algorithm is able to discover the motion path of the GVO automatically and refine its spatial region of support progressively. In addition to object segmentation, the proposed algorithm can also be applied to video pre-processing, removing the so-called ‘video mask’ noise in digital videos. Experimental results show that this type of vision-assisted video pre-processing significantly improves the compression efficiency.