function?imDst?=?boxfilter（imSrc?r）

%???BOXFILTER???O（1）?time?box?filtering?using?cumulative?sum
%
%???-?Definition?imDst（x?y）=sum（sum（imSrc（x-r:x+ry-r:y+r）））;
%???-?Running?time?independent?of?r;?
%???-?Equivalent?to?the?function:?colfilt（imSrc?[2*r+1?2*r+1]?‘sliding‘?@sum）;
%???-?But?much?faster.

[hei?wid]?=?size（imSrc）;
imDst?=?zeros（size（imSrc））;

%cumulative?sum?over?Y?axis
imCum?=?cumsum（imSrc?1）;
%difference?over?Y?axis
imDst（1:r+1?:）?=?imCum（1+r:2*r+1?:）;
imDst（r+2:hei-r?:）?=?imCum（2*r+2:hei?:）?-?imCum（1:hei-2*r-1?:）;
imDst（hei-r+1:hei?:）?=?repmat（imCum（hei?:）?[r?1]）?-?imCum（hei-2*r:hei-r-1?:）;

%cumulative?sum?over?X?axis
imCum?=?cumsum（imDst?2）;
%difference?over?Y?axis
imDst（:?1:r+1）?=?imCum（:?1+r:2*r+1）;
imDst（:?r+2:wid-r）?=?imCum（:?2*r+2:wid）?-?imCum（:?1:wid-2*r-1）;
imDst（:?wid-r+1:wid）?=?repmat（imCum（:?wid）?[1?r]）?-?imCum（:?wid-2*r:wid-r-1）;
end

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2018-08-07?10:58??code\
?????文件?????????931??2013-08-17?23:12??code\boxfilter.m
?????文件????????7495??2013-09-14?22:02??code\darkChannel.m
?????文件??????164274??2013-08-18?14:47??code\ds.jpg
?????文件?????????273??2013-09-13?10:31??code\edge_test.m
?????文件????????1789??2013-09-15?12:19??code\getLaplacian1.asv
?????文件????????1838??2013-09-15?11:26??code\getLaplacian1.m
?????文件???????46029??2013-05-20?17:40??code\guangzhou.jpg
?????文件?????????957??2010-07-08?21:57??code\guidedfilter.m
?????文件????????2464??2013-08-18?12:33??code\guidedfilter_color.asv
?????文件????????2462??2013-08-18?14:20??code\guidedfilter_color.m
?????文件??????595854??2012-11-16?11:24??code\house.bmp
?????文件??????194829??2013-07-01?14:56??code\land.jpg
?????文件??????789207??2009-06-29?17:42??code\ny.png
?????文件?????1479691??2009-06-29?17:43??code\ny17.png
?????文件???????31516??2012-01-05?19:17??code\p2.jpg
?????文件??????919734??2012-01-05?19:17??code\p4.bmp
?????文件???????12363??2013-09-11?09:49??code\s.jpg
?????文件??????161277??2013-06-13?14:03??code\shl.jpg
?????文件????????1254??2013-09-15?11:45??code\softmatting.m
?????文件??????179324??2010-09-29?14:33??code\sweden.jpg
?????文件??????359188??2012-11-16?11:32??code\sy2.jpg
?????文件??????202554??2013-09-14?22:48??code\t.bmp
?????文件?????????189??2018-08-07?11:04??code\test.m
?????文件??????810056??2012-11-13?14:25??code\tiananmen1.bmp
?????文件???????92984??2013-04-03?11:12??code\tokyo.jpg
?????文件??????700972??2009-06-29?17:43??code\y.png
?????文件???????22883??2013-09-14?07:57??code\y_08.jpg
?????文件??????155444??2009-09-16?09:10??code\yellowmountain.jpg