Painting patches:Reducing flicker in painterly re-rendering of video  

作　　者：ZHANG SongHai TONG Qiang HU ShiMin MARTIN Ralph 

机构地区：[1]Department of Computer Science and Technology, Tsinghua University, Beijing 100084, China [2]School of Computer Science and Informatics, Cardiff University, Cardiff, Wales CF24 3AA, UK

出　　处：《Science China(Information Sciences)》2011年第12期2592-2601,共10页中国科学（信息科学）（英文版）

基　　金：supported by the National Basic Research Program of China(Grant No.2011CB302205);the National Natural Science Foundation of China(Grant Nos.60970100,61033012)

摘　　要：This paper presents a novel method for re-rendering video in a stroke-based painterly style. Previous methods typically place and adjust strokes on a frame by frame basis, guided by an analysis of motion vectors. Our method constructs painting patches which last for multiple frames, and paints them just once, compositing them after placing and clipping each one in each output frame. Painting patches are constructed by clustering pixels with similar motions, representing moving objects. This is done using a multi-frame window, to take account of objects which are present in consecutive frames, and which may occur a few frames apart with occlusion. The appearance of a given cluster across a sequence of frames is warped to a common reference to produce the painting patch; a global optimization of the warp is used to minimize distortion in the painting strokes. This approach outperforms prior algorithms in problem areas of the image, where flickering typically occurs, while producing comparable results elsewhere. In particular, stable strokes are produced at occlusion boundaries where objects emerge, and at image borders exposed by camera panning. A further advantage is consistent rendering of regions before and after brief occlusion, enhancing temporal stability of the output of discontiguous frames.

关 键 词：non-photorealistic rendering painterly rendering stroke placement region clustering video ren- dering FLICKER 

分 类 号：TP316.7[自动化与计算机技术—计算机软件与理论] J212.05[自动化与计算机技术—计算机科学与技术]