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% H. R. Sheikh and A. C. Bovik, "Image Information and Visual Quality", IEEE Transactions on 
% Image Processing, (to appear).
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This software release consists of an implementation of the algorithm described in the paper:

H. R. Sheikh and A. C. Bovik, "Image Information and Visual Quality"., IEEE Transactions on Image Processing, (to appear).
Download manuscript draft from http://live.ece.utexas.edu in the Publications link.


It consists of the following files:

readme.txt: this file
vifvec.m: main function, call this to evaluate image quality
support .m files: ind2wtree.m, refparams_vecgsm.m, vifsub_est_M.m

Prerequisites: The Steerable Pyramid toolbox. Available at
http://www.cns.nyu.edu/~lcv/software.html

Input : (1) img1: The reference image as a matrix
        (2) img2: The distorted image (order is important)

Output: (1) VIF the visual information fidelity measure between the two images

Default Usage:
   Given 2 test images img1 and img2, whose dynamic range is 0-255

   vif = vifvec(img1, img2);

Advanced Usage:
   Users may want to modify the parameters in the code. 
   (1) Modify sigma_nsq to find tune for your image dataset.
   (2) MxM is the block size that denotes the size of a vector used in the
   GSM model.
   (3) subbands included in the computation


Please read the paper for more details on interpretation of the results.
Email comments and bug reports to [email protected]