Comparison of different methods to merge SPOT P and XS data: Evaluation in an urban area

Several methods have been developed to merge SPOT multispectral (XS) and panchromatic (P) data. This study evaluates the results of seven methods in the context of an urban and suburban area (Geneva, Switzerland). A statistical and visual comparison has been made for the overall area and for several zones which represent different land cover types including water, forest, green areas, high and low residential areas and apartment-block areas. Mean and standard deviation of the XS bands have been compared with those of the bands obtained after the merging process; the differences and the correlations between the XS and new bands have also been calculated. The aim of the visual comparison is to assess the usefulness of the merged images for visual analysis. The HPF method has obtained the best overall result.