function?[UV]?=?OpticalFlow（Img1Img2iter_numalpha）
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%?This?MATLAB?codes?calculate?optical?flow?of?two?consecutive?frames（images）
%?using?Horn?&?Schunck‘s?method.
%?Input:
%????????Img1Img2??:??image?data
%????????iter_num???:??the?time?of?iteration
%??????????alpha????:??wighting?coefficient
%?Author:
%????????Huazhong?University?of?Science?and?Technology
%???????????Institute?of?Pattern?Recognition?and?Artificial?Intelligence
%???????????????Lee?Chi
%?Contact?me:?leechi1010@163.com
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%%?Pre_process
[height_1width_1dim_1]?=?size（Img1）;
if?dim_1?==?3
????Img1?=?rgb2gray（Img1）;
end
[height_2width_2dim_2]?=?size（Img2