基于Retinex和小波变换的水下偏振图像融合方法

Underwater Polarization Image Fusion Method Based on Retinex and Wavelet Transform

为了改善水下偏振图像质量差、对比度低等问题,提出一种基于Retinex和小波变换的水下偏振图像融合算法。首先,将强度图像进行Retinex增强预处理;然后将强度图像及偏振度图像进行小波分解(DWT),将分解得到的低频分量采用一种基于显著图的融合规则进行融合,高频分量采用像素绝对值取大进行融合;最后对融合后的低频分量和高频分量进行小波逆变换,得到融合增强后的图像。试验结果表明:此算法得到的图像视觉效果更佳,图像细节更加明显,清晰度更高;客观评价上,融合图像在信息熵、对比度、平均梯度上分别提升了6.6%、98.5%、39.2%,水下图像的质量得到了显著提升。

In order to improve the poor quality and low contrast of underwater polarization image,an underwater polarization image fusion algorithm based on Retniex and wavelet transform is proposed.Firstly,the intensity image was preprocessed by Retniex enhancement.Then the intensity image and polarization image were decomposed by wavelet transform(DWT).The low frequency component was fused by a fusion rule based on significance graph,and the high frequency component was fused by increasing the absolute value of pixel.Finally,the inverse wavelet transform was used to obtain the fused enhanced image.The experimental results show that the visual effect of images achieved by this algorithm is better,with more obvious details and higher clarity.Objectively,the information entropy,contrast and average gradient of fused images are improved by 6.6%,98.5%and 39.2%respectively,and the quality of underwater images is significantly improved.