Effects of Brovey transform and wavelet transform on the information capacity of SPOT-5 imagery

Abstract

Image fusion based on a Brovey transform (BT) and wavelet transform (WT) is developed to merge SPOT-5 images. The main objective of this research was to study the effects of BT and WT on the information capacity of panchromatic and multispectral images. The results show that the spatial resolution of images merged by BT and WT is higher than that of the original SPOT-5 images. The two transforms techniques merge the features of the panchromatic and multispectral images very well. However, the hue of the WT merged image is very different from that of the original image, indicating that WT led to obvious color distortion. And the hue of the BT merged image is approximately the same as for the original image, with no image distortion. Furthermore, the discussion of the information capacity considers quality in terms of hue and definition, and quantity in terms of entropy, average gradient and spectral authenticity. Experimental results show that images merged by BT showed higher spatial resolution and better spectral features than the original SPOT-5 imagery. Images merged by WT also showed higher spatial resolution, but lost some spectral information. Therefore, BT is very efficient and highly accurate for merging SPOT-5 images.