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为了使图像压缩后的效果更加符合人眼感知特性，提出了一种结合人眼对比度敏感视觉特性的图像压缩算法.算法首先结合视觉特性和图像变换域频谱系数特征，提出一种图像的角频率的计算方法，并依据计算的角频率提出一种人眼觉察图像最小误差阈值的计算方法；然后以此阈值作为量化步长，提出一种图像变换域频谱系数的量化方法；最后采用霍夫曼编码算法进行编解码，实现图像的压缩.并对三幅彩色图像进行了仿真实验，结果表明：与JPEG技术相比，三幅彩色图和各分量图的平均压缩比、PSNR和 SSIM依次提高了10．4807％、6．9879％和2．6494％.表明提出的结合人眼视觉特性的图像压缩算法是一种较好的、有实用价值的压缩算法.

In order to make the compressed images satisfy more with the human visual perception char-acteristics,a color image compression algorithm combined the human visual contrast sensitivity char-acteristics is proposed.Firstly,combining the characteristics of human visual contrast sensitivity and spectrum coefficients in transform domain of image,a method for calculating the angular frequencies of the images is proposed,and the calculating method of minimum error threshold of human eye detec-ting images is proposed according to the angular frequencies.Then taking the threshold as quantiza-tion step size,a method is proposed to quantize spectrum coefficients in transform domain of image. Finally Huffman coding algorithm is adopted to carry out encoding and decoding to realize image com-pression.And the simulation experiments for three color images is carried out .The results show that the average compression ratio,PSNR and SSIM of three color images and each component of the image are increased by 10.480 7%,6.987 9% and 2.649 4% respectively,compared with the technol-ogy of JPEG.It indicates that the image compression algorithm combined the human visual character-istics is better and more practical.