%??This?Matlab?code?demonstrates?an?edge-based?active?contour?model?as?an?application?of?
%??the?Distance?Regularized?Level?Set?Evolution?（DRLSE）?formulation?in?the?following?paper:
%
%??C.?Li?C.?Xu?C.?Gui?M.?D.?Fox?“Distance?Regularized?Level?Set?Evolution?and?Its?Application?to?Image?Segmentation“?
%?????IEEE?Trans.?Image?Processing?vol.?19?（12）?pp.?3243-3254?2010.
%
%?Author:?Chunming?Li?all?rights?reserved
%?E-mail:?lchunming@gmail.com???
%?????????li_chunming@hotmail.com?
%?URL:??http://www.engr.uconn.edu/~cmli/

clear?all;
close?all;

%Img=imread（‘gourd.bmp‘）;
%Img=imread（‘2.12.jpg‘）;
Img=imread（‘kidney1.jpg‘）;
%Img=rgb2gray（imread（‘a(chǎn)bdomen5.png‘））;
Img=double（Img（::1））;
%%?parameter?setting
timestep=1;??%?time?step
mu=0.2/timestep;??%?coefficient?of?the?distance?regularization?term?R（phi）
iter_inner=5;
iter_outer=1085;
lambda=2;?%?coefficient?of?the?weighted?length?term?L（phi）
alfa=-3;??%?coefficient?of?the?weighted?area?term?A（phi）
epsilon=1.5;?%?papramater?that?specifies?the?width?of?the?DiracDelta?function
epsilon=2.0;
sigma=.8;????%?scale?parameter?in?Gaussian?kernel
G=fspecial（‘gaussian‘15sigma）;?%?Caussian?kernel
Img_smooth=conv2（ImgG‘same‘）;??%?smooth?image?by?Gaussiin?convolution
[IxIy]=gradient（Img_smooth）;
f=Ix.^2+Iy.^2;
g=1./（1+f）;??%?edge?indicator?function.

%?initialize?LSF?as?binary?step?function
c0=2;
initialLSF?=?c0*ones（size（Img））;
%?generate?the?initial?region?R0?as?two?rectangles
%initialLSF（25:3520:25）=-c0;?
%initialLSF（25:3540:50）=-c0;


%-------------------test-------------
%initialLSF（125:175120:125）=-c0;?
%initialLSF（125:175140:150）=-c0;
%phi=initialLSF;

figure;imshow（Img[]）;title（‘initial?circle‘）;

?[yx]=ginput（1）;
??x1?=?round（x（1））;
??y1?=?round（y（1））;
??%x2=round（x（2））;
??%y2=round（y（2））;
??initialLSF（x1:x1+20y1:y1+20）=-c0;
??%initialLSF（x2:x2+50y2:y2+50）=-c0;
??phi=initialLSF;
%----------------end-------------------
figure（1）;
mesh（-phi）;???%?for?a?better?view?the?LSF?is?displayed?upside?down
hold?on;??contour（phi?[00]?‘r‘‘LineWidth‘2）;
title（‘Initial?level?set?function‘）;
view（[-80?35]）;

figure（2）;
imagesc（Img[0?255]）;?axis?off;?axis?equal;?colormap（gray）;?hold?on;??contour（phi?[00]?‘r‘）;
title（‘Initial?zero?level?contour‘）;
pause（0.1）;

potential=2;??
if?potential?==1
????potentialFunction?=?‘single-well‘;??%?use?single?well?potential?p1（s）=0.5*（s-1）^2?which?is?good?for?region-based?model?
elseif?potential?==?2
????potentialFunction?=?‘double-well‘;??%?use?double-well?potential?in?Eq.?（16）?which?is?good?for?both?edge?and?region?based?models
else
????potentialFunction?=?‘double-well‘;??%?default?choice?of?potential?function
end??
?
%?start?level?set?evolution
for?n=1:iter_outer
????phi?=?drlse_edge（phi?g?lambda?mu?alfa?epsilon?timestep?iter_inner?potentialFunction）;????
????if?mod（n2）==0
????????figure（2）;
????????imagesc（Img[0?255]）;?axis?off;?axis?equal;?colormap（gray）;?hold

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

?????文件??????17557??2015-05-08?15:30??DRLSE_v0\2.12.jpg

?????文件??????14107??2015-05-08?15:30??DRLSE_v0\abdomen.jpg

?????文件??????63855??2015-05-08?15:30??DRLSE_v0\abdomen2.jpg

?????文件?????413325??2015-05-08?15:30??DRLSE_v0\abdomen5.png

?????文件???????3945??2015-05-08?16:56??DRLSE_v0\demo_1.m

?????文件???????3257??2015-05-08?15:30??DRLSE_v0\demo_2.m

?????文件????1978453??2015-05-08?15:30??DRLSE_v0\DRLSE.pdf

?????文件???????1474??2015-05-08?15:30??DRLSE_v0\DRLSELabel.mat

?????文件????????899??2015-05-08?15:30??DRLSE_v0\DRLSELabel1.mat

?????文件????????913??2015-05-08?15:30??DRLSE_v0\DRLSELabel2.mat

?????文件???????3595??2015-05-08?15:30??DRLSE_v0\drlse_edge.m

?????文件???????5798??2015-05-08?15:30??DRLSE_v0\gourd.bmp

?????文件??????25037??2015-05-08?15:30??DRLSE_v0\kidney1.jpg

?????文件??????25968??2015-05-08?15:30??DRLSE_v0\liver1.jpg

?????文件??????16434??2015-05-08?15:30??DRLSE_v0\twocells.bmp

?????文件????????662??2015-05-08?15:30??DRLSE_v0\Untitled.m

?????目錄??????????0??2015-05-13?10:24??DRLSE_v0

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

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