分形图像编码是一种很有前途的压缩技术,但编码时间长阻碍了它的广泛应用。分形编码的时间主要花费于在一个海量码本中搜索每个输入子块的最佳匹配块。针对这个问题,提出了一种快速分形编码算法,它基于图像块的分数盒维数特征,能够在较小的搜索范围内完成输入子块的最佳匹配。实验结果显示,该算法能够大大缩短编码时间,同时实现和全搜索分形编码算法相同或更好的图像质量。

Fractal image coding is a very promising compression technique,but it suffers from long encoding time.The time to encode fractally an image is mostly spent on searching for the best-matched block for each of range blocks in a usually-large domain pool.This paper thus proposed a fast fractal encoding algorithm based on fractional box-counting dimension of an image block,which can find out the best-matched block for an input range block with a reduced search.Experimental results show that the proposed algorithm can significantly shorten the encoding time,while achieving the same or better decoded image quality as baseline fractal algorithm with full search.