MATLAB: How to find x-y coordinates of minutia(end points , short ridges) of finger print image , and store it in matrix

minutia in finger print

i have maximum length of short ridges and i want to extract coordinates of it

Best Answer

Assuming the maximum 'area' (not 'length') of short ridges < 50 pixel, I think the following code can detect them.

% Read the image
I = imread('finger3.bmp');
BW = imbinarize(I);
% Measure region properties
stats = regionprops(~BW,{'Area','BoundingBox','PixelList'});
stats = struct2table(stats);
% Assuming the area of short ridge < 50 pixel
idx = stats.Area < 50;
stats = stats(idx,:);
% Show the detected short ridges
imshow(I)
hold on
for kk = 1:height(stats)
  rectangle('Position',stats.BoundingBox(kk,:),'EdgeColor','b')
  plot(stats.PixelList{kk}(:,1), stats.PixelList{kk}(:,2),'r.')
end

Related Solutions

MATLAB: Extraction of rectangular blob from binary image

How about comparing length around the blob and length around the bounding box of the blob, like:

% sample blogs
I = imread('pillsetc.png');
Iblob = rgb2gray(I) > 200;
% measure perimeter and bounding box for each blob
stats = regionprops(Iblob,{'BoundingBox','perimeter'});
stats = struct2table(stats);
% extract the blob whose perimeter is close to round length of its bounding box
stats.Ratio = 2*sum(stats.BoundingBox(:,3:4),2)./stats.Perimeter;
idx = abs(1 - stats.Ratio) < 0.1;
stats(~idx,:) = [];
% show the result
imshow(Iblob);
hold on
for kk = 1:height(stats)
  rectangle('Position', stats.BoundingBox(kk,:),...
      'LineWidth',    3,...
      'EdgeColor',    'g',...
      'LineStyle',    ':');
end

MATLAB: I want to count the number of metric elements in if statement using ‘sum’, but it shown all the content of elements, not the number. I’m new.. pls help..

Way too clumsy. Try something like this (untested):

stats = regionprops(L,'Area','Centroid', 'Perimeter');
allAreas = [stats.Area];
allPerimeters = [stats.Perimeter];
circularities = (4*pi*allAreas) ./ allPerimeters.^2; % Inverted compared to how I use it.
threshold = 0.88;
roundObjects = circularities > threshold;
as = sum(circularities(roundObjects));

Best Answer

Related Solutions

MATLAB: Extraction of rectangular blob from binary image

MATLAB: I want to count the number of metric elements in if statement using ‘sum’, but it shown all the content of elements, not the number. I’m new.. pls help..

Related Question