www.pudn.com > snake_program.rar > caclVF.m

function caclVF(); 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
%%%% calculate Vector field 
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% 
 
%%%% image processing variables 
global Image2;							% blured image 
global mu; 
global NoGVFIterations;				% number of iterations 
global VectorFieldButt;				 
global alpha beta gamma kappa dmin dmax;		% parameters for the snake 
global px py u v;											% forse filed 
global SchangeInFieldType; 
global XSnake YSnake;				% conture of the snake 
 
 
global xsize ysize;					%size of the picture 
 
global adgeD; 
 
%%%%% global handles 
global HDorigPic;						%original picture axes handle 
global HDbluredPic;				   %blured picture axes handle 
global HDvectorFPic;					%handle of vector field picture 
 
global HDvectorFPic; 
global HDSnakeLine;					%vector of Handles of Snake lines on the picture 
global SnakeON;						%indicate if snake is visible 
global SnakeDotsON;				      % 1 if snake dots should be displeyed 
global DotsSize;						% size in pixels of the dots on the snake 
 
 
 
if SchangeInFieldType==1 
	if VectorFieldButt(1)==1 
   	% Compute standard vector filed of Image2 
   	[u,v] = gradient2(Image2); 
	else 
   	 % Compute the GVF of the edge Image2 
    	disp(' Compute GVF ...'); 
    	[u,v] = GVF(Image2, mu, NoGVFIterations);  
   end 
   SchangeInFieldType=0; 
 end 
  
 if VectorFieldButt(3)==1 
  	mag = sqrt(u.*u+v.*v); 
   px = u./(mag+1e-10); py = v./(mag+1e-10);  
 else 
   	px=u; py=v; 
 end 
  
 %HDvectorFPic=subplot(223);  
 global HDmainf; 
 set(HDmainf,'CurrentAxes',HDvectorFPic); 
 xSpace=(1:size(Image2,1)/64:size(Image2,1)); 
 ySpace=(1:size(Image2,2)/64:size(Image2,2)); 
 qx=interp2(px,xSpace, ySpace'); 
 qy=interp2(py,xSpace, ySpace'); 
 
 quiver(xSpace,ySpace,qx,qy); axis('ij'); 
if VectorFieldButt(1)==1 
   title('Standard potencial field'); 
else 
   s=strcat('GVF   (mu=',num2str(mu),'  iterations=',num2str(NoGVFIterations),')'); 
   title(s); 
end 
 
set(HDvectorFPic,'Units', 'pixels','Position',[adgeD adgeD xsize ysize],... 
   					'Units', 'normal',... 
                  'XLim',[0 size(Image2,1)],... 
                  'YLim',[0 size(Image2,2)],... 
                  'XTickMode','manual','XTick',[],... 
                  'YTickMode','manual','YTick',[],... 
                  'Units', 'pixels'); 
                
%%%%% result 
XS=[XSnake; XSnake(1)]; 
YS=[YSnake; YSnake(1)]; 
 
HDline1=line('Parent', HDorigPic,'XData',XS,'YData',YS,'Color','Red'); 
HDline2=line('Parent', HDbluredPic,'XData',XS,'YData',YS,'Color','Red'); 
HDline3=line('Parent', HDvectorFPic,'XData',XS,'YData',YS,'Color','Red'); 
 
HDSnakeLine=[HDline1 HDline2 HDline3]; 
SnakeON=1; 
if SnakeDotsON==1  
   set(HDSnakeLine,'Marker','.','MarkerEdgeColor','Green','MarkerFaceColor','Blue','MarkerSize',DotsSize); 
else 
   set(HDSnakeLine,'Marker','None'); 
end; 
 
                
HD=get(HDvectorFPic,'Children'); 
set(HD,'ButtonDownFcn','SnakeIter(''Pic3Click'')'); 
                
menu3;