Processing: Image Communication, vol. 15, no. 9, pp.
767-779, July 2000
Image Coding Based on Partial Fractal Mapping
1Dept. of Electrical & Computer
Engineering, The Univ. of Texas at Austin, Austin, USA
2 Department of Computing, Hong Kong Polytechnic Univ., Hong Kong,
3 Department of Electronic and Communication Engineering, South
China Univ. of Tech., Guangzhou, China
fractal image compression technique models a natural image using a contractive
mapping called fractal mapping in the image space. In this paper, we
demonstrate that the fractal image coding algorithm is compatible with other
image coding methods. In other words, we can encode only part of the image
using fractal technique and model the remaining part using other algorithms.
According to such an idea, a new mapping in the image space called partial
fractal mapping is proposed. Furthermore, a general framework of fractal-based
hybrid image coding encoding/decoding systems is presented. The framework
provides us with much flexibility for real implementations. Many different
hybrid image coding schemes can be derived from it. Finally, a new hybrid image
coding scheme is proposed where non-fractal coded regions are used to help the
encoding of fractal coded regions. Experiments show that the proposed system
performs better than the quadtree-based fractal image coding algorithm and the
JPEG image compression standard at high compression ratios larger than 30.
Keywords: Image coding;
Fractal; Data compression; Hybrid system