function?[mssim?ssim_map?mcs?cs_map]?=?ssim_index_new（img1?img2?K?window）

if?（nargin??4）
???ssim_index?=?-Inf;
???ssim_map?=?-Inf;
???return;
end

if?（size（img1）?~=?size（img2））
???ssim_index?=?-Inf;
???ssim_map?=?-Inf;
???return;
end

[M?N]?=?size（img1）;

if?（nargin?==?2）
???if?（（M?	???ssim_index?=?-Inf;
	???ssim_map?=?-Inf;
??????return
???end
???window?=?fspecial（‘gaussian‘?11?1.5）;	%
???K（1）?=?0.01;										%?default?settings
???K（2）?=?0.03;										%
end

if?（nargin?==?3）
???if?（（M?	???ssim_index?=?-Inf;
	???ssim_map?=?-Inf;
??????return
???end
???window?=?fspecial（‘gaussian‘?11?1.5）;
???if?（length（K）?==?2）
??????if?（K（1）?		???ssim_index?=?-Inf;
???		ssim_map?=?-Inf;
	???	return;
??????end
???else
	???ssim_index?=?-Inf;
???	ssim_map?=?-Inf;
	???return;
???end
end

if?（nargin?==?4）
???[H?W]?=?size（window）;
???if?（（H*W）??M）?|?（W?>?N））
	???ssim_index?=?-Inf;
	???ssim_map?=?-Inf;
??????return
???end
???if?（length（K）?==?2）
??????if?（K（1）?		???ssim_index?=?-Inf;
???		ssim_map?=?-Inf;
	???	return;
??????end
???else
	???ssim_index?=?-Inf;
???	ssim_map?=?-Inf;
	???return;
???end
end

C1?=?（K（1）*255）^2;
C2?=?（K（2）*255）^2;
window?=?window/sum（sum（window））;

mu1???=?filter2（window?img1?‘valid‘）;
mu2???=?filter2（window?img2?‘valid‘）;
mu1_sq?=?mu1.*mu1;
mu2_sq?=?mu2.*mu2;
mu1_mu2?=?mu1.*mu2;
sigma1_sq?=?filter2（window?img1.*img1?‘valid‘）?-?mu1_sq;
sigma2_sq?=?filter2（window?img2.*img2?‘valid‘）?-?mu2_sq;
sigma12?=?filter2（window?img1.*img2?‘valid‘）?-?mu1_mu2;

if?（C1?>?0?&?C2?>?0）
???ssim_map?=?（（2*mu1_mu2?+?C1）.*（2*sigma12?+?C2））./（（mu1_sq?+?mu2_sq?+?C1）.*（sigma1_sq?+?sigma2_sq?+?C2））;
???cs_map?=?（2*sigma12?+?C2）./（sigma1_sq?+?sigma2_sq?+?C2）;
else
???numerator1?=?2*mu1_mu2?+?C1;
???numerator2?=?2*sigma12?+?C2;
	denominator1?=?mu1_sq?+?mu2_sq?+?C1;
???denominator2?=?sigma1_sq?+?sigma2_sq?+?C2;
???
???ssim_map?=?ones（size（mu1））;
???index?=?（denominator1.*denominator2?>?0）;
???ssim_map（index）?=?（numerator1（index）.*numerator2（index））./（denominator1（index）.*denominator2（index））;
???index?=?（denominator1?~=?0）?&?（denominator2?==?0）;
???ssim_map（index）?=?numerator1（index）./denominator1（index）;
???
???cs_map?=?ones（size（mu1））;
???index?=?denominator2?>?0;
???cs_map（index）?=?numerator2（index）./denominator2（index）;
end

mssim?=?mean2（ssim_map）;
mcs?=?mean2（cs_map）;

return

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????2317??2009-04-15?15:54??ssim_mscale_new.m
?????文件?????????333??2009-04-15?15:54??test.m
?????文件????????2410??2009-04-15?15:53??ssim_index_new.m