how to crop image automatically to 512x512px?

Question

Dayangku Nur Faizah Pengiran Mohamad 2024-5-9

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2117186-how-to-crop-image-automatically-to-512x512px

编辑： Walter Roberson 2024-5-10

1_245.jpg

Hello everyone. I want to crop with the size of 512x512px. But matlab only save the image as 10x9 uint8. and also, I want it to crop at the center of the lesion without any specific area. can the matlab do such that task? here's my code given below and result of the image that not at the center of the lesion.

close all;
I=imread('1_245.jpg');
figure, imshow(I);
I=rgb2gray(I);
BW=I>100;
figure,imshow(BW);
labeledImage = bwlabel(BW);
measurements = regionprops(labeledImage, 'BoundingBox', 'Area');
for k = 1 : length(measurements)
thisBB = measurements(k).BoundingBox;
I2=imcrop(I,[thisBB(1),thisBB(2),thisBB(3),thisBB(4)]);
[rows, cols, depth]=size(I2);
if rows*cols>100
    I2=imresize(I2,[512 512]);
    figure,imshow(I2);
end
end

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

DGM 2024-5-9

在 MATLAB Online 中打开

1_245.jpg

I don't really know what you want, since this code seems to be at odds with what's being described. The given code simplifies to this:

I = imread('1_245.jpg');

I = im2gray(I);

BW = I > 100;

imshow(BW);

measurements = regionprops(BW,'BoundingBox');

for k = 1 : numel(measurements)

thisBB = measurements(k).BoundingBox;

thisIm = imcrop(I,thisBB); % the cropped image

% if the box area is above a certain size

if prod(thisBB(3:4)+1) > 100

% stretch the image, misrepresenting its actual shape

thisIm = imresize(thisIm,[512 512]);

% display the region??

imshow(thisIm);

drawnow

pause(0.1)

end

If you're after the green annotation, it doesn't make sense to me that you're looking for all bright gray regions. If you're wanting to crop a specific area for illustration or analysis, it doesn't make sense to me that you'd stretch it out and throw away all the information about its original shape.

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2024-5-10

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/2117186-how-to-crop-image-automatically-to-512x512px#answer_1455341

编辑：Walter Roberson 2024-5-10

在 MATLAB Online 中打开

RegionSize = 512;
I=imread('1_245.jpg');
figure, imshow(I);
I=rgb2gray(I);
BW=I>100;
figure,imshow(BW);
labeledImage = bwlabel(BW);
measurements = regionprops(labeledImage, 'BoundingBox', 'Area');
for k = 1 : length(measurements)
    thisBB = measurements(k).BoundingBox;
    
    thismid =  thisBB(1:2) + thisBB(3:4)/2;
    startpos = floor(max(1, thismid - RegionSize/2));
    I2 = imcrop(I,[startpos, RegionSize, RegionSize]);
    filename = "l_245_crop_" + k + ".jpg";
    imwrite(I2, filename);
end