Fractal Compression of Images with Projected IFS
Résumé
Standard fractal image compression, proposed by Jacquin,
is based on IFS (Iterated Function Systems) defined in
R². This modelization implies
restrictions in the set of images being able to be compressed. These
images have to be self similar in R². We propose a new
model, the projected IFS, to approximate and code grey level images.
This model has the ability to define affine IFS
in a high dimension space, and to project it through control points, resulting in
a non strictly self similar object in R². We proposed a method
for approximating curves with such a model.
In this paper, we
extend the model capabilities to surfaces and images. This includes
the combination of projected IFS in a quadtree structure and a complete
coding scheme. First results show that our method gives better results than
standard fractal image compression. Furthermore, in the very low bitrate
context, the distortion/rate performances are equivalent
to those obtained with EZW algorithm.