Fractal image compression is based on the rather poorly motivated assumption that “natural” images exhibit significant affine self-similarity. The accuracy of this assumption is evaluated by a comparison between the statistics of natural images and those of a multiresolution stochastic model designed to generate images exhibiting affine self-similarity as assumed by fractal coding techniques. T...

In this paper, a novel wavelet subtree partitioning algorithm is proposed, which divides a subtree into scalar quantized wavelet coefficients and fractal coded sub-subtree. Based on this new technique, a variable size wavelet subtree fractal coding scheme for still image compression is developed. Experimental results show that the new scheme can achieve nearly optimal partition of wavelet subtr...

Fixed block size fractal coding is evaluated for rst-order Gauss-Markov models, and the eeects of varying the correlation are presented. Performance for this class of statistical models is found to be poor compared with traditional techniques such as transform coding.

Fixed block size fractal coding is evaluated for first-order Gauss-Markov models, and the effects of varying the correlation are presented. Performance for this class of statistical models is found to be poor compared with traditional techniques such as transform coding.

A new digital watermark approach based on fractal image coding is proposed in this letter. We present a way to use the fractal code as a means of embedding a watermark. The proposed approach has shown to be resistant to the JPEG lossy compression. Moreover, the digital watermark can be simply extracted from the watermarked image without resorting to the original image. key words: digital waterm...

Fractal image coding has the advantage of higher compression ratio, but is a lossy compression scheme. The encoding procedure consists of dividing the image into range blocks and domain blocks and then it takes a range block and matches it with the domain block. The image is encoded by partitioning the domain block and using Affine transformation to achieve fractal compression. The image is rec...

In this paper, we present a fractal image compression algorithm employing a new quadtree recomposition (QR) approach. In this approach, quadtree subblocks of an image are iteratively recombined into larger blocks for fractal coding. For complex images, this approach exhibits superior runtime performance, when compared to a classical quadtree decomposition (QD) scheme, while maintaining high del...

In fractal image compression, the code is given by a contractive aane mapping whose xed point is an approximation to the original image. Usually, the mapping is found by the collage coding method. We propose an algorithm that starts from an initial mapping obtained by collage coding and iteratively provides a sequence of contractive mappings whose xed points are monotonically approaching the or...

We study the delity/compression performance of fractal image coding, and evaluate the merits or otherwise of a number of complexity options. We can rst of all choose a quantization scheme for the transmission of coeecients which limits the code alphabet, according to permissible degradations. This alphabet can then be entropy coded to eliminate redundancy so that the compression eeciency of a r...