A Method Of Fractal Image Compression Based On Region Partition

The method of fractal image compression transfers a digital into a group of contract iterate function system (IPS) model. Encoding IFS's parameters achieves image compression. This method may gain higher compression ratio,as well as decoding rapidly. To many not strictiy self-similar image,the usual fractal image compression method based on block partition divides the image into non-overlap regular shape block collection. Every block's iterate function system is found out by local self-similarity. The parameters of all iterate function system form fractal image compression code.In this paper,a fractal image compression method based on region partition is devised. The first chapter introduces the significance of fractal image compression research and the valuation standard of image quality. The second chapter sets forth the theorem basis of fractal image compression. By researching the property of iterate function system in metric space,two basic theorems are brought outthe fixed-point theorem of contract mapping and collage theorem. In the third chapter,fractal image compression method based on block partition is discussed and implemented. The original image is divided into non-overlap square domain block collection and range collection,which is fourfold the domain block. To every domain block,the best self-similarity transformation is gained by matching the found best similar range block,The parameters of the gained best domain block's transformations are the image compression code. The fourth chapter discusses and implements fractal image compression method based on region partition. Firstly,the least square region collection and neighboring regions pair queue are gained,by initiating using the method referred in the third chapter. Following,under a given fixed sign to noise rate,the best neighboring domain region pair is combined continually in according with the least collage error principle. Finally,the image region collection comprises many irregular shape regions. The image compression code is gained byencoding the parameter of the self-similar transformation and shapes of regions. In comparison with the abilities of two fractal image compressions,the fractal image compression method based on region partition can gain higher compression ratio as the same of sign to noise rate,which compression ability is improved obviously.