Fusion of satellite images of different spatial resolutions: Assessing the quality of resulting images

TLDR

Methods exist to generate multispectral images with higher spatial resolution by fusing multiple higher‑resolution images of the same scene. This study defines the properties of enhanced multispectral images, focusing on the quality of multispectral content when spatial resolution is increased. The authors propose a formal framework with five quantitative criteria to assess spectral quality when synthesizing radiometry and multispectral information during spatial resolution enhancement, illustrated using a SPOT image and three standard methods. The study finds that landscape type and scale significantly influence the assessment of spectral quality.

Abstract

Methods have been proposed to produce multispectral images with enhanced spatial resolution using one or more images of the same scene of better spatial resolution. Assuming that the main concern of the user is the quality of the transformation of the multispectral content when increasing the spatial resolution, this paper defines the properties of such enhanced multispectral images. It then proposes both a formal approach and some criteria to provide a quantitative assessment of the spectral quality of these products. Five sets of criteria are defined. They measure the pe$ormance of a method to synthesize the radiometry in a single spectral band as well as the multispectral information when increasing the spatial resolution. The influence of the type of landscape present in the scene upon the assessment of the quality is underlined, as well as its dependence with scale. The whole approach is illustrated by the case of a SPOT image and three different standard methods to enhance the spatial resolution.