binary mask for the coordinates using MATLAB
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I need to create a binary mask. I have some coordinates and I make those coordinates and inside that region equal to 1, and background equal to zero. The image size is 600*800
Here is what I have done, but the problem is ROI located not in the correct position and located on the right bottom of the image. I appreciate if someone could point me to the right direction.
X and Y coordinates are attached here, The first col is X and the second Y. Basically, [X(1) Y(1)] is refereing to the pixels on the image.
Here the left is what snippet did produce and the right image is my expectation
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/289391/image.png)
Here is my snippet:
function [X,Y, BW] = Create_mask(X,Y,im)
X = round(X);
Y = round(Y);
X ( X < 1 ) = 1;
Y ( Y < 1 ) = 1;
BW = im > 255;
for p = 1:length(X)
BW(Y(p),X(p)) = 1;
end
%connect the end of curve
for n = 0:(1/round(sqrt((X(end)-X(1))^2 + (Y(end)-Y(1))^2 ))):1
xn = round(X(1) +(X(end) - X(1))*n);
yn = round(Y(1) +(Y(end) - Y(1))*n);
BW(yn,xn) = 1;
end
se = strel('disk',10);
BW = imclose(BW,se);
BW = imdilate(BW,se);
BW = imfill(BW,'holes');
im( im < 255 ) = 0;
im = imclose(im,se);
BW = BW * 255;
BW = im2uint8(BW);
figure;
imshow(BW);
% close all;
end
4 Comments
Answers (1)
Ameer Hamza
on 1 May 2020
Edited: Ameer Hamza
on 1 May 2020
What about just shifting the x and y coordinates
x = H_D{1}(:,1);
y = H_D{1}(:,2);
im = zeros(600, 800);
mask = Create_mask(x-300, y-300, im);
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/289454/image.png)
Also, I recommend that instead of creating your own function to convert x, y coordinates to mask, you can do it with built-in function in a single line
x = H_D{1}(:,1);
y = H_D{1}(:,2);
im = poly2mask(x-300, y-300, 600, 800);
2 Comments
Ameer Hamza
on 1 May 2020
Edited: Ameer Hamza
on 1 May 2020
I just made a guess. It appeared similar to the image you have shown in the question. I think that the actual points themself cannot create the mask you want. Some sort of shifting is necessary.
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