How to find the broadest width of contour and calculate it.

Hello everybody,

I would like to know, where my contour(1440 in the picture) is broadest (considering the y-direction for the width) and calculate it.

I read a lot but I am not sure which suggestion would be the best for my case (interp2, In2bw,...).

Thank you very much for your help,

Alina

Answer 1

[Image Analyst]

Try this (untested)

binaryImage = grayImage >= 1440
binaryImage = bwareafilt(binaryImage, 1); % Extract only the largest blob.
[rows, columns] = size(binaryImage);
for col = 1 : columns
        thisColumn = binaryImage(:, col);
        topRow(col) = find(thisColumn, 1, 'first');
        bottomRow(col)= find(thisColumn, 1, 'last');
        heights(col) = bottomRow(col) - topRow(col);
end
maxHeight = max(heights);
columnsOfMaxHeight = find(heights == maxHeight); % Might be more than one column with max height!
% Draw it
hold on;
for k = 1 : length(columnsOfMaxHeight)
        thisCol = columnsOfMaxHeight(k);
        line([thisCol, thisCol], [topRow(thisCol), bottomRow(thisCol)], 'Color', 'r', 'LineWidth', 2)
end

Let me know of any problems.

[AliAlemana]

Dear Image Analyst,

I am very sorry I reply so late, I found an easier solution than yours but still, thank you very very much for the fast and helpful answer!

[Image Analyst]

What was your easier solution?