BibTex Entry:

@InProceedings{OBWBTS08:DiffusionCurves,
  author       = "Orzan, Alexandrina and Bousseau, Adrien and Winnem{\"o}ller, Holger and Barla, Pascal and Thollot, Jo{\"e}lle and Salesin, David",
  title        = "Diffusion Curves: A Vector Representation for Smooth-Shaded Images",
  booktitle    = "ACM Transactions on Graphics (Proceedings of SIGGRAPH 2008)",
  volume       = "27",
  year         = "2008",
  url          = "http://artis.imag.fr/Publications/2008/OBWBTS08",
  abstract     = {We describe a new vector-based primitive for creating smooth-shaded images, called the diffusion curve. A 
		diffusion curve partitions the space through which it is drawn, defining different colors on either side. 
		These colors may vary smoothly along the curve. In addition, the sharpness of the color transition from 
		one side of the curve to the other can be controlled. Given a set of diffusion curves, the final image is 
		constructed by solving a Poisson equation whose constraints are specified by the set of gradients across 
		all diffusion curves. Like all vector-based primitives, diffusion curves conveniently support a variety 
		of operations, including geometry-based editing, keyframe animation, and ready stylization. Moreover, 
		their representation is compact and inherently resolution-independent. We describe a GPU-based 
		implementation for rendering images defined by a set of diffusion curves in realtime. We then demonstrate 
		an interactive drawing system for allowing artists to create artworks using diffusion curves, either by 
		drawing the curves in a freehand style, or by tracing existing imagery. The system is simple and 
		intuitive: we show results created by artists after just a few minutes of instruction. Furthermore, we 
		describe a completely automatic conversion process for taking an image and turning it into a set of 
		diffusion curves that closely approximate the original image content.}
}