Atistic Paper-cut for Human Portrait
    Meng Meng1  Mingtian Zhao1,2   
        Song-Chun Zhu1,2 
        1Lotus Hill Institute;    
        2University of California, Los Angeles
         
     
     
    
        1. Some results and how do we express computer-generated facial paper-cut 
                 
         
         
        
         
        
        
          
            | Paper-cut is a traditional decorative art which is originated in China 2000   years ago. It is a binary image converted from real gray images(s) under a set   of flexible constrains of geometric connectivity. However, from the perspective   of paper-cut artists, it is a skill of not only cutting a piece of folded paper   but also designing the artistic style for a particular human face in a specific   posture, emotional expression, illumination, etc. Experienced artists will seize   the most impressive features from the portrait or a real person at the first   glance, and transform them into corresponding paper-cut components   simultaneously, this is the basic rule for artistic rendering, but gives us a   creative perspective in rendering artistic facial paper-cut from portrait.  | 
           
         
          
        
        2. Ideas from image parsing 
                 
                 
         
         
                
         
         
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        Since a valid facial paper-cut is a combination of  a series of paper-cut components  representative for each facial feature, we thus adopt the idea of image parsing  inspired by the method proposed by Xu  et al, in which a three-layer generative model is presented and fine face  sketches are generated from a coarse to fine computation.  The parsing graph illustrate a vivid  process through which an intact face is  decomposed into correlated nodes, more details are retained in dealing with  each and-node, such as laugh lines, play a crucial role in depicting human  facial  expression.  | 
         
    
    
        3. Preserve identity while rendering artistic styles  
                 
         
          
        
 
        
         
          
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            We lay emphasis on two aspects in the paper-cut  rendering process: preserving the identity of the face so that it can be  recognized and simulating the artistic style of paper-cut  from the view of empirical artists.  Our method first calls for a balance between  the binarized feature serving as shading  information and the shape information provided directly by the portrait, a set  of candidate templates for a particular facial feature( left eyebrow, right  eyebrow, left eye, right eye, nose, mouth, face contour, laugh lines)are  calculated through minimizing a weighed distance. Artistic style varies with a  changing weighed parameter, such as a precise approximation of the portrait, or  exaggeration based on particular configuration of facial features,    it is up to the user to identify which is the most satisfying one.  Finally a connection layer is added to the previous result to satisfy the  geometric constrain of paper-cut. From observing a large number of manual  portrait paper-cuts, several fixed patterns are appropriate for facial feature  connection  which are both physically  adaptive and aesthetically pleasing. 
              
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    References 
        
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                [1] Zijian Xu, Hong Chen, Song-Chun Zhu and Jiebo Luo, "A hierarchical compositional model for face representation and
                sketching," IEEE Trans. Pattern Analysis and Machine Intelligence(PAMI)'08.
                 
                [2] Feng Min, Jin-Li Suo, Song-Chun Zhu  and Nong Sang, "An Automatic Portrait System Based on And-Or Graph Representation",                EMMCVPR 2007 |    
        
    
    
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