Lin Zhang, Lei Zhang, Xuanqin Mou, and David Zhang,”FSIM: a feature similarity index for image qualtiy assessment”, IEEE Transactions on Image Processing, vol. 20, no. 8, pp. 2378-2386, 2011.
(1) imageRef: the first image being compared
(2) imageDis: the second image being compared
(1) FSIM: is the similarty score calculated using FSIM algorithm. FSIM only considers the luminance component of images. For colorful images, they will be converted to the grayscale at first.
(2) FSIMc: is the similarity score calculated using FSIMc algorithm. FSIMc considers both the grayscale and the color information.
Note: For grayscale images, the returned FSIM and FSIMc are the same.