Spectrum Similarity-Based Quality Assessment Metric

Pansharpening is the fusion of panchromatic (PAN) and multispectral (MS) images to obtain a high spectral and spatial resolution image. Various metrics are introduced to assess the performance of different algorithms of pansharpening. This paper proposes a new metric for spectral quality evaluation of fused images. In the proposed method, spectrum vector of each pixel of fused image is compared to corresponding spectrum of reference image. Area of difference between two spectra is measured, and by applying this process to all pixel vectors of the fused image and taking an average over obtained values, spectral distortion of whole image is obtained. To investigate the efficiency of the proposed index, deliberate spectral distortion is applied to fused image and the proposed metric's ability to detect distortion is examined. Experimental results on real remote sensing images demonstrate the superior performance of the proposed metric compared to other existing metrics.