I want to fined the centroid , then distance from centroid to boundary for each object in image

I want to fined the centroid, then the distance from centroid to boundaries for each object inside, down there is a code it's work but for one object can any one help to fined for all object, i think i must put a for loop to pass on each object to calculate the centroid then distance , and after finish go to next object and so on , please can any body help with thanks.

clc; % Clear the command window. close all; % Close all figures (except those of imtool.) clear; % Erase all existing variables. Or clearvars if you want. workspace; % Make sure the workspace panel is showing. format long g; format compact; fontSize = 12;

%=============================================================================== grayImage = imread('Enew.png'); imshow(grayImage); title('Original');

% Threshold the image to make it binary. binaryImage = grayImage > 128; binaryImage = bwareafilt(binaryImage, 1); % Take largest blob. binaryImage = imfill(binaryImage, 'holes'); % fill holes. % Display the image. subplot(2, 2, 1); imshow(binaryImage, []); title('Original Binary Image', 'FontSize', fontSize, 'Interpreter', 'None');

% Set up figure properties: % Enlarge figure to full screen. set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]); % Get rid of tool bar and pulldown menus that are along top of figure. set(gcf, 'Toolbar', 'none', 'Menu', 'none'); % Give a name to the title bar. set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off')

% bwboundaries() returns a cell array, where each cell contains the row/column coordinates for an object in the image. % Plot the borders of all the coins on the original grayscale image using the coordinates returned by bwboundaries. subplot(2, 2, 2); imshow(binaryImage); title('Outlines, from bwboundaries()', 'FontSize', fontSize); axis image; % Make sure image is not artificially stretched because of screen's aspect ratio. hold on; boundaries = bwboundaries(binaryImage); numberOfBoundaries = size(boundaries, 1) for k = 1 : numberOfBoundaries thisBoundary = boundaries{k}; plot(thisBoundary(:,2), thisBoundary(:,1), 'r', 'LineWidth', 3); end x = thisBoundary(:, 2); y = thisBoundary(:, 1); hold off;

% Find centroid. labeledImage = bwlabel(binaryImage); measurements = regionprops(labeledImage, 'Centroid'); xCentroid = measurements.Centroid(1); yCentroid = measurements.Centroid(2); subplot(2, 2, 3); imshow(binaryImage); title('Binary Image with Lines', 'FontSize', fontSize); hold on; plot(xCentroid, yCentroid, 'r*', 'MarkerSize', 10, 'LineWidth', 2);

% Find distances. distances = sqrt((x-xCentroid).^2 + (y-yCentroid).^2);

% Display the histogram of distances. subplot(2, 2, 4); histogram(distances, 20); caption = sprintf('Histogram of distances\nfrom center to all other points.'); title(caption, 'FontSize', fontSize, 'Interpreter', 'None'); xlabel('Distance', 'FontSize', fontSize); ylabel('Count', 'FontSize', fontSize); % Compute the mean distance meanDistance = mean(distances) % Put a red line there on the histogram. line([meanDistance, meanDistance], ylim, 'Color', 'r', 'LineWidth', 2); grid on; % Label the mean on the plot. yl = ylim(); % Get range of y axis. caption = sprintf(' Mean distance = %.2f pixels', meanDistance) text(meanDistance, 0.95*yl(2), caption, 'FontSize', 14, 'FontWeight', 'bold', 'Color', 'r');

Answer 1

[Image Analyst]

Simply label the image, extract each region one at a time, and compute the centroid and boundaries and distances. Full code is attached.

[alaa shamasneh]

Dear Image analyst thanks for your answer, i appreciate this. This is great work but i have an error when am trying to run the attached code please can you check for me what the error here thanks

[alaa shamasneh]

Its okay i solve it i using strfind instead of contains its working now thanks image analyst.Really you are the best.

[Image Analyst]

You must have an old version of MATLAB before contains() was introduced.

[alaa shamasneh]

I want to change the place to make distance on y axis and count on x axis ,in histogram i change the last part as next , and i attached the histogram figure the change is correct or no ?

% Put a red line there on the histogram.
  line([meanDistance, meanDistance], xlim, 'Color', 'r', 'LineWidth', 2);
  grid on;
  % Label the mean on the plot.
  xl = xlim(); % Get range of y axis.
  caption = sprintf('  Mean distance = %.2f pixels', meanDistance)
  text(meanDistance, 0.95*xl(2), caption, 'FontSize', 14, 'FontWeight', 'bold', 'Color', 'r');

[Image Analyst]

It should say ylim instead of xlim:

line([meanDistance, meanDistance], ylim, 'Color', 'r', 'LineWidth', 2);

because the y bottom and top limits are the second argument to line().

[alaa shamasneh]

Noted with thanks sir.

[alaa shamasneh]

Dear image analyst can you help me on this two steps

1- If the centorid of the component falls on the same component (white pixels) or near to it, I can remove this object. this step after calculate the centroid and before calculate the distance and angle histogram

2- I calculate the angle from centroid to boundaries and i represented as a histogram also , can you check if its right cause i notice the values for some object have a high angle value and suppose not cause the centroid near to boundaries suppose angle be small.

[alaa shamasneh]

Dear image analyst can you help please

[alaa shamasneh]

please can anybody help ???

[Image Analyst]

Define "or near to it" -- how many pixels is that?

[Image Analyst]

Try this:

% See if this blob's centroid is one of the blob's white pixels.
  smallestAllowableDistance = 2; % Whatever.
  closePixels = distances < smallestAllowableDistance;
  if any(closePixels)
    % Centroid is close to one of the white pixels.
    % Find out how close
    promptMessage = sprintf('Skipping blob #%d of %d because some pixels\nare closer to the centroid than %d pixels.\nThe closest is %.1f pixels away.', ...
      regionIndex, numberOfRegions, smallestAllowableDistance, min(distances));
    titleBarCaption = 'Continue?';
    buttonText = questdlg(promptMessage, titleBarCaption, 'Continue', 'Quit', 'Continue');
    if contains(buttonText, 'Quit')
      return;
    end
    subplot(2, 3, 6);
    cla; % Clear out old results.
    title('Too Close', 'FontSize', fontSize);
    continue;
  end
  
  % Get the pixel Coordinates of the boundaries
  xBoundary = measurements(regionIndex).PixelList(:, 1);
  yBoundary = measurements(regionIndex).PixelList(:, 2);
  theseAngles = atan2d(yBoundary - yCentroid, xBoundary - xCentroid);

Full Demo attached.

[Image Analyst]

alaa, I haven't heard back from you. Did that work for you?

[alaa shamasneh]

Dear Image analyst, thanks for your answer i will check and comeback to you. So sorry cause i didn't comeback to you before just cause i was travelling. I will check and comeback to you soon. Really thanks for you

[QuestionsAccount]

dear @Image Analyst i know that question is asked a very long time ago and also asked by someone else i want to put my question here becasue my problem was similar to the above one.

Image Analyst i tried your above provided code https://www.mathworks.com/matlabcentral/answers/411550-i-want-to-fined-the-centroid-then-distance-from-centroid-to-boundary-for-each-object-in-image#answer_329876 I just want to ask you that instead of histograme that we display in this code at the end if i want to display the image which showing distances from the centroid then how can i do that? what i wanted to do or what i m asking is attached in image actually i want to find distance from center to boundry points and then display them as after connecting them with center in order to make skeleton of human body.

your help in this regard is highly appriciated.