help with "imfindcircles"
显示 更早的评论
Hello! i am having trouble finding the centroid of this petri dish.
when i run my code, matlab finds 12 centroids and when i use 'viscircles' its showing me 12 rings on top of each other. could this be a sensitivity issue? are there other ways i can eliminate the other circles and only detect the boundary of the petri dish?
here is my code and i have also attached the image im analyzing and the resultant image after running the code
for i = 1:numI
file = images(i).name;
img = imread(file);
imshow(file)
% d = drawline;
% pos = d.Position;
% diffPos = diff(pos);
% diameter = hypot(diffPos(1),diffPos(2));
[C,R] = imfindcircles(img,200,'ObjectPolarity','dark','Sensitivity',1);
end
v = viscircles(C,R);
采纳的回答
Image Analyst
2020-12-5
Post your original image, rather than a screenshot.
For one thing, your image capture conditions are horrible. You need to have lights on both sides to get rid of that bad shadow that is essentially the same darkness as your petri dish. If you had that, you could simply threshold and call regionprops:
mask = grayImage < someThresholdValue;
% Take largest blob.
mask = bwareafilt(mask, 1);
% Fill holes
mask = imfill(mask, 'holes');
% Find centroid
props = regionprops(mask, 'Centroid', 'EquivDiameter')
xCenter = props.Centroid(1)
yCenter = props.Centroid(2)
diameter = props.EquivDiameter
2 个评论
Chaman Srivastava
2020-12-21
Hey! Image Analyst.
Really appreciate your answers!
I have a question regarding imfindcircles command in Matlab. Why is that it always return interger values if i specify a range in the command. Any insights on this? Is there any method to extract much accurate values?
Image Analyst
2020-12-22
Not sure. I don't really use it that much. Maybe it always wants to put the center on a definite row and column. You can call them and ask them or edit imfindcircles.m to see the source code.
更多回答（0 个）
类别
在 帮助中心 和 File Exchange 中查找有关 Image Processing Toolbox 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
