【摘要】 EZW静态图像压缩算法,由于充分利用了小波变换图像的良好性质,引起了图像数据压缩领域的广泛注意。EZW算法被认为是静态图像变换编码领域迄今为止最好的算法之一。通过对EZW算法及其改进算法的介绍,分析了这些算法存在的不足,并提出一种简单而有效的静态图像压缩算法,根据图像经小波分解后系数的特点和人眼视觉特性对Shapiro的EZW算法进行改进。由于人眼对图像的边缘信息的丢失非常敏感,改进后的算法更加注重边缘信息的编码,实验结果表明,重构后的图像更加清晰,尤其在低比特率时更加明显。更多还原

【Abstract】 EZW approach is a competitive technique for performance as compared with other coding techniques as it makes use of the ex-cellent characteristic of wavelet transform.Firstly,the embedded zerotree wavelet algorithm(EZW) and its improved methods are in-troduced and then their deficiency is discussed.A simple,yet effective still image compression algorithm is described.According to the characteristic of coefficients and human visual system(HVS),an attempt is made to improve Shapiro’s EZW algorithm.The enhanced algorithm pays more attention to the edge of one image because human visual system is sensitive to edge information.Experimeptal results show that the enhanced algorithm performs better than that of EZW in image quality,especially in the case of low rate.更多还原