Spatial Quality Evaluation of Fusion of Different Resolution Images

Spatial quality and spectral quality are the two important indexes that are used to evaluate the quality of any fused image. Most of the existing methods for this purpose, however, considered only the spectral quality except for that proposed by Zhou et al., while the latter cannot be used to compare directly the spatial resolution between the fused image and original high-resolution. A new spatial quality assessment approach was presented in the paper based on the blur parameter estimation. It is based fact that the blur parameter, which is a measure of the spread of the sensor’s point spread function (PSF), characterizes the spatial resolution of the sensor image. The merged images derived from IHS, PCA, HPF, and AWL methods are compared in order to evaluate the performance of the proposed spatial quality measure. Experimental results demonstrate that the spatial quality measure based on the blur parameter is more efficient in judging spatial quality of the fused image. The blur parameter is an objective quality measure based on a basic optical mechanism and thus can be used to evaluate the effectiveness of various processing or fusion schemes in terms of spatial quality of the fused image. It is also shown that the spatial resolution of the fused images can not completely match with the same spatial resolution of the high-resolution panchromatic image. The proposed approach is based upon simple concepts, easy to understand and easy to implement and use.