I need source code for trianguating (delaunay triangulation) minutiae points extracted from a fingerprint image

The code below helps to fetch minutiae points from a given fingerprint image

% This program extracts the ridges and bifurcation from a fingerprint image

% Read Input Image
binary_image=im2bw(imread('image.tif'));

% Small region is taken to show output clear
binary_image = binary_image(120:400,20:250);
figure;imshow(binary_image);title('Input image');

% Thinning
thin_image=~bwmorph(binary_image,'thin',Inf);
figure;imshow(thin_image);title('Thinned Image');

% Minutiae extraction
s=size(thin_image);
N=3;%window size
n=(N-1)/2;
r=s(1)+2*n;
c=s(2)+2*n;
double temp(r,c);   
temp=zeros(r,c);bifurcation=zeros(r,c);ridge=zeros(r,c);
temp((n+1):(end-n),(n+1):(end-n))=thin_image(:,:);
outImg=zeros(r,c,3);%For Display
outImg(:,:,1) = temp .* 255;
outImg(:,:,2) = temp .* 255;
outImg(:,:,3) = temp .* 255;
for x=(n+1+10):(s(1)+n-10)
    for y=(n+1+10):(s(2)+n-10)
        e=1;
        for k=x-n:x+n
            f=1;
            for l=y-n:y+n
                mat(e,f)=temp(k,l);
                f=f+1;
            end
            e=e+1;
        end;
         if(mat(2,2)==0)
            ridge(x,y)=sum(sum(~mat));
            bifurcation(x,y)=sum(sum(~mat));
         end
    end;
end;

% RIDGE END FINDING
[ridge_x ridge_y]=find(ridge==2);
len=length(ridge_x);
%For Display
for i=1:len
    outImg((ridge_x(i)-3):(ridge_x(i)+3),(ridge_y(i)-3),2:3)=0;
    outImg((ridge_x(i)-3):(ridge_x(i)+3),(ridge_y(i)+3),2:3)=0;
    outImg((ridge_x(i)-3),(ridge_y(i)-3):(ridge_y(i)+3),2:3)=0;
    outImg((ridge_x(i)+3),(ridge_y(i)-3):(ridge_y(i)+3),2:3)=0;

      outImg((ridge_x(i)-3):(ridge_x(i)+3),(ridge_y(i)-3),1)=255;
      outImg((ridge_x(i)-3):(ridge_x(i)+3),(ridge_y(i)+3),1)=255;

[Matt Kindig]

Why don't the built-in delaunay triangulation functions work?

doc DelaunayTri

[VictorMaria]

it works, but not directly

[Walter Roberson]

I am not sure what you mean by "not directly" in this situation ?

[farheen]

can any 1 explaim me this code??i am new in matlab...want to use this code..bt not getting it

[yogita bade]

sorry , but can you give expla

nation for this code plese??????

Answer 1

[Aditya]

you should iteratively figure out what each step of the code does.