function?[y0detectx0detectAccumulator]?=?houghcircle（Imbinaryrthreshnumpeaks）
%HOUGHCIRCLE?-?detects?circles?with?specific?radius?in?a?binary?image.
%
%Comments:
%???????Function?uses?Standard?Hough?Transform?to?detect?circles?in?a?binary?image.
%???????According?to?the?Hough?Transform?for?circles?each?pixel?in?image?space
%???????corresponds?to?a?circle?in?Hough?space?and?vise?versa.?
%???????upper?left?corner?of?image?is?the?origin?of?coordinate?system.
%
%Usage:?[y0detectx0detectAccumulator]?=?houghcircle（Imbinaryrthresh）
%
%Arguments:
%???????Imbinary?-?a?binary?image.?image?pixels?that?have?value?equal?to?1?are
%??????????????????interested?pixels?for?HOUGHLINE?function.
%???????r????????-?radius?of?circles.
%???????thresh???-?a?threshold?value?that?determines?the?minimum?number?of
%??????????????????pixels?that?belong?to?a?circle?in?image?space.?threshold?must?be
%??????????????????bigger?than?or?equal?to?4（default）.
%
%Returns:
%???????y0detect????-?row?coordinates?of?detected?circles.
%???????x0detect????-?column?coordinates?of?detected?circles.?
%???????Accumulator?-?the?accumulator?array?in?Hough?space.
%
%Written?by?:
%???????Amin?Sarafraz
%???????Photogrammetry?&?Computer?Vision?Devision
%???????Geomatics?DepartmentFaculty?of?Engineering
%???????University?of?TehranIran
%???????sarafraz@geomatics.ut.ac.ir
%
%May?52004?????????-?Original?version
%November?242004???-?Modified?versionfaster?and?better?performance


if?nargin?==?2
????thresh?=?4;
????numpeaks=1;
elseif?nargin?==?3
????numpeaks=1;
end
if?thresh?????error（‘treshold?value?must?be?bigger?or?equal?to?4‘）;
????return
end

%Voting
Accumulator?=?zeros（size（Imbinary））;
[yIndex?xIndex]?=?find（Imbinary）;
for?cnt?=?1:length（xIndex）
????low=xIndex（cnt）-r;
????high=xIndex（cnt）+r;
????if?（low<1）?low=1;?end
????if?（high>size（Imbinary2））?high=size（Imbinary2）;?end
????for?x0?=?low:high
????????y01?=?yIndex（cnt）-sqrt（r^2-（xIndex（cnt）-x0）^2）;
????????y02?=?yIndex（cnt）+sqrt（r^2-（xIndex（cnt）-x0）^2）;
????????y01?=?round（y01）;?y02?=?round（y02）;
????????if?y01?=?1
????????????Accumulator（y01x0）?=?Accumulator（y01x0）+1;
????????end
????????if?y02?=?1
????????????Accumulator（y02x0）?=?Accumulator（y02x0）+1;
????????end
????end
end

%?Finding?local?maxima?in?Accumulator
Accumulatortemp?=?Accumulator?-?thresh;
%?[Potential_y0?Potential_x0]=find（Accumulatortemp<0）;
%?Accumulatortemp（Potential_y0Potential_x0）=0;
[y0detect?x0detect?hnew]?=?houghpeaks_circle（Accumulatortempnumpeaks）;
%?y0detect?=?[];?x0detect?=?[];
%?AccumulatorbinaryMax?=?imregionalmax（Accumulator）;
%?[Potential_y0?Potential_x0]?=?find（AccumulatorbinaryMax?==?1）;
%?Accumulatortemp?=?Accumulator?-?thresh;
%?for?cnt?=?1:length（Potential_y0）
%?????if?Accumulatortemp（Potential_y0（cnt）Potential_x0（cnt））?>=?0
%?????????y0detect?=?[y0detect;Potential_y0（cnt）];
%?????????x0detect?=?[x0dete

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----

?????文件???????3044??2010-01-08?21:54??霍夫圓變換\houghcircle.m

?????文件???????2718??2010-01-08?19:18??霍夫圓變換\houghpeaks_circle.m

?????文件???????3182??2010-01-09?21:44??霍夫圓變換\hough_circle_feed.m

?????目錄??????????0??2010-05-04?22:37??霍夫圓變換

-----------?---------??----------?-----??----

?????????????????8944????????????????????4