.
Inkwell: A 2 ½-D animation system
Peter C. Litwinowicz.
SIGGRAPH '91, pp. 113--122,
1991. [BibTeX]
Non-Photorealistic Rendering
Stuart Green, David H. Salesin, Simon Schofield, Aaron Hertzmann, Peter C. Litwinowicz, Amy A. Gooch, Cassidy J. Curtis, Bruce Gooch.
Siggraph 99, ACM Press, Course 17,
1999. [BibTeX]
Processing images and video for an impressionist effect
Author(s): Peter C. Litwinowicz.
Proceedings: SIGGRAPH '97: Proceedings of the 24th annual conference on Computer graphics and interactive techniques, pp. 407--414, New York, NY, USA, ACM Press/Addison-Wesley Publishing Co.,
1997.
[BibTeX] [DOI] 
Abstract:
This paper describes a technique that transforms ordinary video segments into animations that have a hand-painted look. Our method is the first to exploit temporal coherence in video clips to design an automatic filter with a hand-drawn animation quality, in this case, one that produces an Impressionist effect. Off-the-shelf image processing and rendering techniques are employed, modified and combined in a novel way. This paper proceeds through the process step by step, providing helpful hints for tuning the off-the-shelf parts as well as describing the new techniques and bookkeeping used to glue the parts together.