A Fast Fractal Image Compression Algorithm Using Improved Quadtree Partitioning Scheme

摘要

By presenting an improved quadtree partitioning scheme and by modifying the composition method of the classical domain pool, we propose a fast fractal image compression algorithm. In our partitioning scheme, a square image is divided into four equal-sized square blocks, and then each block is tested to see if it meets some criterion of homogeneity. If a block meets the criterion, it is not divided any further. If it does not meet the criterion, it is subdivided again into four blocks, and the test criterion is applied to those blocks. This process is repeated iteratively until each block meets the criterion. Also, the proposed algorithm is validated and is compared with the classic fractal image compression algorithm. Experimental results show that the proposed algorithm can almost achieve the same reconstructed image quality as the classic algorithm, and can greatly reduce the encoding time and improve the compression ratio.