基于自适应四叉树分块和DCT变换的大幅面图像分形压缩算法

自Barnsley提出图像分形压缩编码的概念，特别是Jacquin给出了第一个完全由计算机自动完成的图像编码算法以及Fisher提出了一种自适应四叉树的图像分块方法以来，图像分形编码得到了越来越多的研究，但图像分形压缩往往需要较长时间，这就给具体应用特别是大副面图像的压缩应用带来了困难。该文首先介绍了Fisher提出的基于自适应四叉树分块的图像分形压缩方法，然后在此基础上结合离散余弦变换（DCT）提出了改进算法。实验结果表明，这种改进算法在保持一定重建图像质量和较高压缩比的前提下，编码时间大大减少，对大副面图像的分形压缩非常实用。

Large-scale Image FractalCompression Algorithm Based on Adaptive Quadtree Partition and DCT

Since Barnsley presented the concept of fractal image compression,especially after Jacquin proposeda fully automatic image compression algorithm and Fisher gave a method of adaptive quadtree image partition,fractal imagecoding has attracted a great deal of research. However,it also needs much time,thus it is difficult to put it into effect especially for large-scale image. After this paper introduces Fisher＇s fractal image compression,an improved method is developed based on adaptive quadtree partition and Discrete Cosine Transform(DCT). Experimental results show that this new approach needs less coding time with no obvious depression on the quality of the reconstructed image and high compression ratio,so it is practicable to large-scale image fractal compression.