Diameter of a droplet using image processing

I would like to know how to get the maximum diameter of a droplet using image processing toolbox.

[Deependra Kumar]

I have worked on same problem.

here is the github code link:- https://github.com/DeepsDK4/Droplet_Spreading_diameter/tree/main/Droplet%20diameter%20calculation

Answer 1

[DGM]

A simple method that works at least for this image:

A = rgb2gray(imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/782708/image.jpeg'));
A = imfill(bwareafilt(A<50,1),'holes');

S = regionprops(A,'boundingbox');

blobwidth = S.BoundingBox(3) % in pixels

blobwidth = 622

% show the extents for reference
imshow(A); hold on
rectangle('position',S.BoundingBox,'edgecolor','y')

You'll have to convert that to mm.

Answer 2

[yanqi liu]

sir，please check the follow code to get some information

for more information,you can read the book 《计算机视觉与深度学习实战》，Thank you！

clc; clear all; close all;
im = imread('https://www.mathworks.com/matlabcentral/answers/uploaded_files/782708/image.jpeg');
im = rgb2gray(im);
bw = imbinarize(im,'adaptive','ForegroundPolarity','dark','Sensitivity',0.85);
bw = imclearborder(bw);
bw = bwareaopen(bw, 100);
[L,num] = bwlabel(bw);
stats = regionprops(L);
figure; imshow(im);
for i = 1 : num
    recti = stats(i).BoundingBox;
    ceni = stats(i).Centroid;
    hold on; rectangle('position', recti, 'EdgeColor', 'g', 'LineWidth', 2)
    text(ceni(1), ceni(2), sprintf('width=%.1f', recti(3)), 'Color', 'r');
end

figure; imshow(bw);

rects=cat(1,stats.BoundingBox);
disp(max(rects(:, 3)))

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