function?[mssim?ssim_map]?=?ssim（img1?img2?K?window?L）
?
%?========================================================================
%?SSIM?Index?with?automatic?downsampling?Version?1.0
%?Copyright（c）?2009?Zhou?Wang
%?All?Rights?Reserved.
%
%?----------------------------------------------------------------------
%?Permission?to?use?copy?or?modify?this?software?and?its?documentation
%?for?educational?and?research?purposes?only?and?without?fee?is?hereby
%?granted?provided?that?this?copyright?notice?and?the?original?authors‘
%?names?appear?on?all?copies?and?supporting?documentation.?This?program
%?shall?not?be?used?rewritten?or?adapted?as?the?basis?of?a?commercial
%?software?or?hardware?product?without?first?obtaining?permission?of?the
%?authors.?The?authors?make?no?re