摘要： 针对分形编码不能直接用于半调图像的问题，结合有序抖动半调图像特点改造仿射变换，提出一种基于分形特征的的半调图像无损压缩算法。对分块后的半调图像进行块匹配编码，从中提取码本，并记录相应的编码参数，利用哈夫曼编码对码本和编码参数做进一步压缩。实验结果表明，该算法的压缩效率较高。

关键词: 有序抖动半调图像, 分形特征, 自相似性, 仿射变换, 码本, 无损压缩

Abstract: In order to solve the problem that fractal image code can not directly used in halftone images, a lossless algorithm is proposed based on improved affine transform with the characteristic of ordered dither images. The transform is used in the extraction of codebook from partitioned images and encoding process, and the Huffman coding is adopted to compress the data. Experimental results show that the algorithm can get better compress efficiency.

Key words: ordered dither halftone image, fractal feature, self-similarity, affine transform, codebook, lossless compression

中图分类号: 

• TN911.73