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??2016-01-11?11:15??fast-guided-filter-code-v1\
?????文件?????1680646??2016-01-11?10:45??fast-guided-filter-code-v1\Fast?guided?filter.pdf
?????文件?????????931??2010-07-08?19:30??fast-guided-filter-code-v1\boxfilter.m
?????文件?????????759??2015-05-05?15:02??fast-guided-filter-code-v1\example_enhancement.m
?????文件?????????426??2015-05-02?22:02??fast-guided-filter-code-v1\example_feathering.m
?????文件?????????716??2015-05-02?22:01??fast-guided-filter-code-v1\example_flash.m
?????文件?????????407??2015-05-05?14:53??fast-guided-filter-code-v1\example_smoothing.m
?????文件?????2179793??2016-01-11?10:46??fast-guided-filter-code-v1\fast-guided-filter-code-v1.rar
?????文件????????1300??2015-05-05?15:01??fast-guided-filter-code-v1\fastguidedfilter.m
?????文件????????3092??2015-05-05?15:01??fast-guided-filter-code-v1\fastguidedfilter_color.m
?????文件?????????957??2010-07-08?21:57??fast-guided-filter-code-v1\guidedfilter.m
?????文件????????2462??2011-05-03?04:12??fast-guided-filter-code-v1\guidedfilter_color.m
?????目錄???????????0??2016-01-11?11:15??fast-guided-filter-code-v1\img_enhancement\
?????文件?????2880056??2010-03-05?16:09??fast-guided-filter-code-v1\img_enhancement\tulips.bmp
?????目錄???????????0??2016-01-11?11:15??fast-guided-filter-code-v1\img_feathering\
?????文件??????947480??2010-07-08?22:24??fast-guided-filter-code-v1\img_feathering\toy-mask.bmp
?????文件??????947480??2010-07-08?22:24??fast-guided-filter-code-v1\img_feathering\toy.bmp
?????目錄???????????0??2016-01-11?11:15??fast-guided-filter-code-v1\img_flash\
?????文件??????786488??2010-02-24?13:31??fast-guided-filter-code-v1\img_flash\cave-flash.bmp
?????文件??????786488??2010-02-24?13:30??fast-guided-filter-code-v1\img_flash\cave-noflash.bmp
?????目錄???????????0??2016-01-11?11:15??fast-guided-filter-code-v1\img_smoothing\
?????文件???????77256??2010-02-27?16:16??fast-guided-filter-code-v1\img_smoothing\cat.bmp
?????文件????????1021??2015-05-02?22:03??fast-guided-filter-code-v1\readme.txt