function?[?map?r?c?]?=?susanCorner（?img?）
%SUSAN?Corner?detection?using?SUSAN?method.
%???[R?C]?=?SUSAN（IMG）	Rows?and?columns?of?corner?points?are?returned.
%	Edward?@?THUEE?xjed09@gmail.com
maskSz?=?[7?7];
fun?=?@（img）?susanFun（img）;
map?=?nlfilter（imgmaskSzfun）;
[r?c]?=?find（map）;

end

function?res?=?susanFun（img）
%?SUSANFUN??Determine?if?the?center?of?the?image?patch?IMG
%	is?corner（res?=?1）?or?not（res?=?0）


mask?=?[...
	0?0?1?1?1?0?0
	0?1?1?1?1?1?0
	1?1?1?1?1?1?1
	1?1?1?1?1?1?1
	1?1?1?1?1?1?1
	0?1?1?1?1?1?0
	0?0?1?1?1?0?0];

%?uses?2?thresholds?to?distinguish?corners?from?edges
thGeo?=?（nnz（mask）-1）*.2;
thGeo1?=?（nnz（mask）-1）*.4;
thGeo2?=?（nnz（mask）-1）*.4;
thT?=?.07;
thT1?=?.04;

sz?=?size（img1）;
usan?=?ones（sz）*img（round（sz/2）round（sz/2））;

similar?=?（abs（usan-img）similar?=?similar.*mask;
res?=?sum（similar（:））;
if?res?	dark?=?nnz（（img-usan<-thT1）.*mask）;
	bright?=?nnz（（img-usan>thT1）.*mask）;
	res?=?min（darkbright）