function?[Lambda1Lambda2IxIy]=eig2image（DxxDxyDyy）
%?This?function?eig2image?calculates?the?eigen?values?from?the
%?hessian?matrix?sorted?by?abs?value.?And?gives?the?direction
%?of?the?ridge?（eigenvector?smallest?eigenvalue）?.
%?
%?[Lambda1Lambda2IxIy]=eig2image（DxxDxyDyy）
%

%
%?|?Dxx??Dxy?|
%?|??????????|
%?|?Dxy??Dyy?|


%?Compute?the?eigenvectors?of?J?v1?and?v2
tmp?=?sqrt（（Dxx?-?Dyy）.^2?+?4*Dxy.^2）;
v2x?=?2*Dxy;?v2y?=?Dyy?-?Dxx?+?tmp;

%?Normalize
mag?=?sqrt（v2x.^2?+?v2y.^2）;?i?=?（mag?~=?0）;
v2x（i）?=?v2x（i）./mag（i）;
v2y（i）?=?v2y（i）./mag（i）;

%?The?eigenvectors?are?orthogonal
v1x?=?-v2y;?
v1y?=?v2x;

%?Compute?the?eigenvalues
mu1?=?0.5*（Dxx?+?Dyy?+?tmp）;
mu2?=?0.5*（Dxx?+?Dyy?-?tmp）;

%?Sort?eigen?values?by?absolute?value?abs（Lambda1）check=abs（mu1）>abs（mu2）;

Lambda1=mu1;?Lambda1（check）=mu2（check）;
Lambda2=mu2;?Lambda2（check）=mu1（check）;

Ix=v1x;?Ix（check）=v2x（check）;
Iy=v1y;?Iy（check）=v2y（check）;

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件????????986??2009-10-27?10:46??frangi_filter_version2a\eig2image.m

?????文件??????12432??2009-08-26?10:14??frangi_filter_version2a\eig3volume.c

?????文件??????????0??2009-10-02?09:37??frangi_filter_version2a\eig3volume.m

?????文件????3938164??2009-06-11?10:40??frangi_filter_version2a\ExampleVolumeStent.mat

?????文件???????3976??2009-12-02?17:02??frangi_filter_version2a\FrangiFilter2D.m

?????文件???????5657??2010-03-02?11:05??frangi_filter_version2a\FrangiFilter3D.m

?????文件???????1025??2009-06-11?11:19??frangi_filter_version2a\Hessian2D.m

?????文件???????1938??2009-06-11?11:23??frangi_filter_version2a\Hessian3D.m

?????文件??????22500??2009-09-30?15:33??frangi_filter_version2a\imgaussian.c

?????文件???????2073??2009-09-24?14:09??frangi_filter_version2a\imgaussian.m

?????文件???????1335??2010-03-02?05:09??frangi_filter_version2a\license.txt

?????文件?????747574??2009-11-08?13:46??frangi_filter_version2a\origin.bmp

?????文件?????263222??2011-04-22?09:51??frangi_filter_version2a\result.bmp

?????文件?????116255??2009-06-11?10:03??frangi_filter_version2a\vessel.png

?????目錄??????????0??2012-07-03?15:29??frangi_filter_version2a

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

??????????????5117137????????????????????15