关键词: 融合, 颜色, 保真, 低通比值融合法

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）