Vectorizing Cartoon Animations

We present a system for vectorizing 2D raster format cartoon animations. The output animations are visually flicker free, smaller in file size, and easy to edit. We identify decorative lines separately from colored regions. We use an accurate and semantically meaningful image decomposition algorithm, supporting an arbitrary color model for each region. To ensure temporal coherence in the output, we reconstruct a universal background for all frames and separately extract foreground regions. Simple user-assistance is required to complete the background. Each region and decorative line is vectorized and stored together with their motions from frame to frame. The contributions of this paper are: 1) the new trapped-ball segmentation method, which is fast, supports nonuniformly colored regions, and allows robust region segmentation even in the presence of imperfectly linked region edges, 2) the separate handling of decorative lines as special objects during image decomposition, avoiding results containing multiple short, thin oversegmented regions, and 3) extraction of a single patch-based background for all frames, which provides a basis for consistent, flicker-free animations.

[1]  Chandrajit L. Bajaj,et al.  Sampling and reconstructing manifolds using alpha-shapes , 1997, CCCG.

[2]  Tien-Tsin Wong,et al.  Manga colorization , 2006, ACM Trans. Graph..

[3]  Milan Sonka,et al.  Image Processing, Analysis and Machine Vision , 1993, Springer US.

[4]  David G. Lowe,et al.  Object recognition from local scale-invariant features , 1999, Proceedings of the Seventh IEEE International Conference on Computer Vision.

[5]  Jirí Zára,et al.  Video Codec for Classical Cartoon Animations with Hardware Accelerated Playback , 2005, ISVC.

[6]  William A. Barrett,et al.  Object-based vectorization for interactive image editing , 2006, The Visual Computer.

[7]  Xin Liu,et al.  Video shot segmentation and classification , 2000, Proceedings 15th International Conference on Pattern Recognition. ICPR-2000.

[8]  Andrew Zisserman,et al.  Learning Layered Motion Segmentation of Video , 2005, ICCV.

[9]  Nebojsa Jojic,et al.  Consistent segmentation for optical flow estimation , 2005, Tenth IEEE International Conference on Computer Vision (ICCV'05) Volume 1.

[10]  Irena Koprinska,et al.  Temporal video segmentation: A survey , 2001, Signal Process. Image Commun..

[11]  Jirí Zára,et al.  Sketching Cartoons by Example , 2005, SBM.

[12]  Wim H. Hesselink,et al.  A General Algorithm for Computing Distance Transforms in Linear Time , 2000, ISMM.

[13]  Carsten Steger,et al.  An Unbiased Detector of Curvilinear Structures , 1998, IEEE Trans. Pattern Anal. Mach. Intell..

[14]  Bruno Lévy,et al.  Ardeco: automatic region detection and conversion , 2006, EGSR '06.

[15]  Harry Shum,et al.  Image vectorization using optimized gradient meshes , 2007, ACM Trans. Graph..

[16]  Dorin Comaniciu,et al.  Mean Shift: A Robust Approach Toward Feature Space Analysis , 2002, IEEE Trans. Pattern Anal. Mach. Intell..

[17]  Peter Meer,et al.  Synergism in low level vision , 2002, Object recognition supported by user interaction for service robots.

[18]  W. Eric L. Grimson,et al.  Adaptive background mixture models for real-time tracking , 1999, Proceedings. 1999 IEEE Computer Society Conference on Computer Vision and Pattern Recognition (Cat. No PR00149).

[19]  Nikos Paragios,et al.  Background modeling and subtraction of dynamic scenes , 2003, Proceedings Ninth IEEE International Conference on Computer Vision.

[20]  Mubarak Shah,et al.  Motion layer extraction in the presence of occlusion using graph cuts , 2004, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[21]  John F. Canny,et al.  A Computational Approach to Edge Detection , 1986, IEEE Transactions on Pattern Analysis and Machine Intelligence.

[22]  Jirí Zára,et al.  Colorization of black-and-white cartoons , 2005, Image Vis. Comput..

[23]  Sung Yong Shin,et al.  Tour into the video: image-based navigation scheme for video sequences of dynamic scenes , 2002, VRST '02.