Table of Contents
ISRN Signal Processing
Volume 2011, Article ID 359592, 9 pages
http://dx.doi.org/10.5402/2011/359592
Research Article

Combining Fractal Coding and Orthogonal Linear Transforms

Biometric and Image Processing Laboratory (BIPLab), University of Salerno, via Ponte don Melillo, 84084 Fisciano (SA), Italy

Received 2 February 2011; Accepted 8 March 2011

Academic Editors: M. Barkat and W. Liu

Copyright © 2011 Michele Nappi and Daniel Riccio. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Many desirable properties make fractals a powerful mathematic model applied in several image processing and pattern recognition tasks: image coding, segmentation, feature extraction, and indexing, just to cite some of them. Unfortunately, they are based on a strong asymmetric scheme, consequently suffering from very high coding times. On the other side, linear transforms are quite time balanced, allowing them to be usefully exploited in realtime applications, but they do not provide comparable performances with respect to the image quality for high bit rates. In this paper, we investigate different levels of embedding orthogonal linear transforms in the fractal coding scheme. Experimental results show a clear improved quality for compression ratios up to 15 : 1.