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 = 20;%===============================================================================
% Have user browse for a file, from a specified "starting folder."
% For convenience in browsing, set a starting folder from which to browse.
startingFolder = pwdif ~exist(startingFolder, 'dir') % If that folder doesn't exist, just start in the current folder.
startingFolder = pwd;end% Get the name of the file that the user wants to use.
defaultFileName = fullfile(startingFolder, '*.png');[baseFileName, folder] = uigetfile(defaultFileName, 'Select a file');if baseFileName == 0 % User clicked the Cancel button.
return;end% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);% Check if file exists.
if ~exist(fullFileName, 'file') % The file doesn't exist -- didn't find it there in that folder.
% Check the entire search path (other folders) for the file by stripping off the folder.
fullFileNameOnSearchPath = baseFileName; % No path this time.
if ~exist(fullFileNameOnSearchPath, 'file') % Still didn't find it. Alert user.
errorMessage = sprintf('Error: %s does not exist in the search path folders.', fullFileName); uiwait(warndlg(errorMessage)); return; endendgrayImage = imread(fullFileName);% Get the dimensions of the image.
% numberOfColorChannels should be = 1 for a gray scale image, and 3 for an RGB color image.
[rows, columns, numberOfColorChannels] = size(grayImage);if numberOfColorChannels > 1 % It's not really gray scale like we expected - it's color.
% Use weighted sum of ALL channels to create a gray scale image.
grayImage = rgb2gray(grayImage); % ALTERNATE METHOD: Convert it to gray scale by taking only the green channel,
% which in a typical snapshot will be the least noisy channel.
% grayImage = grayImage(:, :, 2); % Take green channel.
end% Display the image.
subplot(2, 2, 1);imshow(grayImage, []);title('Original Grayscale Image', 'FontSize', fontSize, 'Interpreter', 'None');hp = impixelinfo;axis on;%------------------------------------------------------------------------------
% Set up figure properties:
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0, 0.04, 1, 0.96]);drawnow;% Crop the image to get rid of feet and legs.
grayImage = grayImage(50, :);% Filter the image with a top hat filter.
filteredImage = imtophat(grayImage, true(50));% Display the image.subplot(2, 2, 2);imshow(filteredImage, []);title('Filtered Image', 'FontSize', fontSize, 'Interpreter', 'None');% Display the image.subplot(2, 2, 3);histogram(filteredImage);title('Histogram of Filtered Image', 'FontSize', fontSize, 'Interpreter', 'None');grid on;% Threshold the image.
% threshold(filteredImage)
binaryImage = filteredImage > 15; % Hgh enough to get rid of bad JPEG artifacts. Never use JPEG for image analysis!
% Display the image.subplot(2, 2, 4);imshow(binaryImage, []);title('Binary Image', 'FontSize', fontSize, 'Interpreter', 'None');% Extract largest blob only
binaryImage = bwareafilt(binaryImage, 1);% Display the image.subplot(2, 2, 4);imshow(binaryImage, []);title('Binary Image', 'FontSize', fontSize, 'Interpreter', 'None');% Find mean intensity
props = regionprops(binaryImage, grayImage, 'MeanIntensity', 'MaxIntensity');meanIntensity = props.MeanIntensityMaxIntensity = props.MaxIntensity% Find hottest spot.
% Get coordinates of pixels in the mask.
[rows, columns] = find(grayImage == MaxIntensity);% Put a cross at every such intensity on the original image
subplot(2, 2, 1);hold on;for k = 1 : length(rows) xHottestSpot = columns(k); yHottestSpot = rows(k); plot(xHottestSpot, yHottestSpot, 'r+', 'MarkerSize', 20, 'LineWidth', 2);endmessage = sprintf('Number of pixels with max intensity of %f = %d.\n',... MaxIntensity, length(rows))uiwait(helpdlg(message));
IN THE ABOVE CODE WHAT IS THE MEANING OF LINE filteredImage = imtophat(grayImage, true(50));
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