GDF: A Novel Image Fusion Approach for Compelling Depiction of Earthly Features

Abstract

One of the most challenging aspects of satellite remote sensing is image fusion. Image fusion increases the visual interpretation of the image and has many applications such as monitoring water bodies, land cover, urbanisation, agriculture, national defence, and so forth. Remote sensing applications require images with a high spatial and spectral resolution for accurately processing and distinguishing the land cover classes with fine texture and shape details. Due to technical limitations, most satellites cannot take high-resolution multi-spectral images but can get high-resolution panchromatic images and low-resolution multi-spectral satellite images separately. This article proposes a novel fusion method, geospatial data fusion (GDF), to obtain high-resolution multi-spectral images. GDF, along with three well-known fusion methods viz., Brovey Transform (BT), wavelet transform (WT), and Fourier transform (FT), have been comparatively implemented to fuse the Cartosat-2 and Sentinel-2 imageries of the Sangam area of Prayagraj, India. The fusion has been done to extract the earth’s surface features from the fused imagery. In this research, the fused image is utilised for river water mapping. Results confirm that the GDF outperforms other existing fusion methods and successfully maps the river water in the study area.