MATLAB: How to plot intensity profile of an image

Image Processing Toolboximprofileintensity profile

I want to plot the intensity profile of this image. I tried using improfile but I don't really know how it works. Can anyone help?

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Like this?

I = imread('Capture.PNG');
x = [0 size(I,2)];
y = [size(I,1)/2 size(I,1)/2];
c = improfile(I,x,y);
figure
subplot(2,1,1)
imshow(I)
hold on
plot(x,y,'r')
subplot(2,1,2)
plot(c(:,1,1),'r')
hold on
plot(c(:,1,2),'g')
plot(c(:,1,3),'b')

Related Solutions

MATLAB: How to plot both horizontal and vertical profile for the same image

Try this:

grayImage = imread('moon.tif');
[rows, columns, numberOfColorChannels] = size(grayImage);
% 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
imshow(grayImage, []);
axis on;
verticalProfile = mean(grayImage, 2);
horizontalProfile = mean(grayImage, 1);
hold on;
% Plot horizontal profile.
x = 1 : columns;
amplitude = 2; % Scaling factor

y = rows - amplitude * horizontalProfile;
plot(x, y, 'r-', 'LineWidth', 2);
% Plot vertical profile.
y = 1 : rows;
amplitude = 1; % Scaling factor
x = columns - amplitude * verticalProfile; % To plot on RIGHT side
x = amplitude * verticalProfile; % To plot on LEFT side
plot(x, y, 'm-', 'LineWidth', 2);

If you'd rather, you can do

verticalProfile = grayImage(:, columnIndex);
horizontalProfile = grayImage(rowIndex, :);

where you specify the row and column where you want the profile to go through.

MATLAB: How to plot Intensity profile along the vertical line of an image

y = [0 size(I,1)];
x = [size(I,2)/2 size(I,2)/2];

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Related Solutions

MATLAB: How to plot both horizontal and vertical profile for the same image

MATLAB: How to plot Intensity profile along the vertical line of an image

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