Abstract: The production’s colors of Brovey transform differ from those of the low spatial resolution multi-spectral image. This paper analyzes the Brovey transform，and then proposes an improved method called panchromatic image low-pass filter based Ratio Fusion（Low-pass RF），whose production’s color is accordant with that of the multi-spectral image.This paper discusses its theory mechanism in terms of radiancy.The results of visual interpretation and quantitative analysis to gray variance index show that the Low-pass RF transform has a capability of retaining color from multi-spectral image.Classification accuracy of the fused image by Low-pass RF transform is higher than that of the Brovey image.Therefore，Low-pass RF transform is more excellent than Brovey transform.

Key words: fusion, color, retaining, Low-pass filter based Ratio Fusion（Low-pass RF）

摘要： 针对遥感图像融合Brovey变换法存在颜色失真的现象，提出了一种低通比值融合法，该融合法首先对高几何分辨率的全色波段进行低能滤波，尔后将低分辨率多光谱图像与全色波段图像相乘，再除以滤波后的全色波段图像，便得到融合图像。从辐照的角度证明了该低通比值融合法具备理论基础，并从目视评价、定量分析、分类精度证实了该低通比值融合法优于Brovey变换法，该低通比值融合法是一种能较好地保全低分辨率多光谱图像颜色的融合方法。

关键词: 融合, 颜色, 保真, 低通比值融合法