Improvement of Fractal Image Coding in the DCT Domain

On the research of the fractal image coding in DCT domain,this paper presents an improved algorithm.In the improved algorithm,plain blocks are selected based on human visual system.Then by selecting out the uniform parts in the DCT domain,the direct current encodes directly without any fractal matching.For matching time reducing,the mean squared error computations of the eight orientations of the domain blocks are simply reduced into two groups of inner products in the DCT domain.The result shows for the same matching errors,this algorithm not only makes the image compressed effectively with high PSNR and much better visual effect,but also reduces processing time in an efficient way.