Hi Naomi,
Assuming plotting an “isodose” curve means drawing contours at specific intensity levels. Here's how you can do it using MATLAB:
- Load and convert the image to double for better precision since we are working with intensity values.
- Define what intensity values you're interested in for plotting the isodose curves. Since the image provided has white circular regions, you might be interested in higher intensity values. Pixel values in an 8-bit grayscale image range from 0 (black) to 255 (white).
- Use the “contour” function to plot the isodose curves. You'll need to generate a grid of X, Y coordinates that match the dimensions of your image. To know more about the “contour” function you can refer the followig link: https://www.mathworks.com/help/matlab/ref/contour.html
This will generate a plot with contours drawn at the specified intensity levels (isodose curves), effectively showing the boundaries of the circular regions if the levels are chosen correctly.
Here is an example code that works in MATLAB R2023b for the above:
img = imread('Image.png');
if size(img, 3) == 3
img = rgb2gray(img);
end
imgDouble = double(img);
% Assuming you're interested in high intensity but not exactly white
% to capture the boundary of the circular regions
isodoseLevels = linspace(200, 250, 3); % Example levels, adjust as needed
[X, Y] = meshgrid(1:size(imgDouble,2), 1:size(imgDouble,1));
figure;
contour(X, Y, imgDouble, isodoseLevels, 'LineWidth', 2);
colormap(jet); % Use a colorful colormap to distinguish levels
colorbar;
title('Isodose Curves for the Image');
xlabel('X-axis');
ylabel('Y-axis');
axis equal tight; % Adjust axis scaling and limits
Hope it helps.
