Cropping an image with coordinate values
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Commented: Image Analyst on 4 Jan 2023
I have an image with 848*1102 pixels after edge detection, and I want to crop out a part of the image accurately, so I need to use the coordinate values of the top left and bottom right points. How do I get the coordinates of these two points and crop the image?
Image Analyst on 2 Jan 2023
Edited: Image Analyst on 2 Jan 2023
grayImage = imread('001.jpg');
[rows, columns, numberOfColorChannels] = size(grayImage)
if numberOfColorChannels == 3
grayImage = grayImage(:, :, 2);
subplot(2, 1, 1);
mask = grayImage > 128;
% Get rid of things touching the border.
mask = imclearborder(mask);
% Label the image
[LabeledImage, numBlobs] = bwlabel(mask);
% Eliminate the outermost blob, which will have a label of 1. Just keep blobs labeled 2 and up.
mask = ismember(LabeledImage, 2:numBlobs);
% Find the corners of the remaining blobs -- the bounding box.
[r, c] = find(mask);
row1 = min(r)
row2 = max(r)
col1 = min(c)
col2 = max(c)
% Do the cropping
mask = mask(row1:row2, col1:col2, :);
subplot(2, 1, 2);
Image Analyst on 4 Jan 2023
Since it's a sphere, and the curved part won't move very much from image to image, I suggestion you just make up a template mask that you can multiply by your image to erase everything outside it. Just take the attached mask and set your gray scale image, or segmented binary image, outside it to zero.
grayImage(~mask) = 0;
That way nothing on the border or any of those spurious reflections will appear after masking.
More Answers (1)
KALYAN ACHARJYA on 2 Jan 2023
Get the indices as rows & colm
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