小波变换和直方图均衡化的保持色调不变彩色图像增强算法

Color image enhancement algorithm based on wavelet transform and histogram equal ization

彩色图像增强的目的是保持色调的前提下加强图 像对比度,提高彩色图像视觉效果,文中提出小波变换域内色调不变 彩色图像增强算法,RGB彩色空间中,对各通道进行小波分解,高频部分进行非线性变换, 突出细节信息,然后通过小波逆 变换重构图像,然后对图像进行限制对比度直方图均衡化后与原图比较算出增强因子,最后 处理gamut问题,得到保持色调 不变的增强图像,在相同条件下与其它彩色图像增强算法进行性能比较,实验结果表明,该 算法对质量不同的彩色图像有较 好的增强效果,增强了图像细节和对比度,并具有自适应能力。

The purpose of color image enhancement is to enhance the image contras t and improve the visual effect of color image on the premise of maintaining the hue.In this paper,a color image′ enhancement alg orithm based on wavelet transform is proposed.In RGB color space,each channel is decomposed by wavelet transform,and the high frequ ency compenent is enhanced by nonlinear function to highlight the details.and the image is reconstructed by inverse wavelet transfor m,Then,the enhancement factor is calculated by comparing the image with the original image after histogram equalization,and th e gamut problem is processed to obtain the hue preserving enhanced image.The performance of the algorithm is compared with oth er color image enhancement algorithms under the same conditions.Experimental results show that the algorithm has good enhanceme nt effect on color images with different quality, enhances image details and contrast,and has adaptive ability.