How to find the intensity of each pixel of an image?
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Consider an image sample.jpg Now I want to count the number of pixels on that image have intensity value larger than 200(white pixels).
If the image contain such pixels above 75% then I want to reject the image. How can I accomplish this in matlab?
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Doug Hull
le 6 Sep 2013
What format is the image in? RGB or greyscale? If it is just a greyscale image, it is really just a matrix and you can do any calculations on it like you would any matrix in MATLAB.
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Image Analyst
le 6 Sep 2013
Modifié(e) : Image Analyst
le 6 Sep 2013
If it's a color image, first convert to a gray image
[rows, columns, numberofColorChannels] = size(originalImage);
if numberofColorChannels > 1
grayImage = rgb2gray(originalImage);
else
grayImage = originalImage;
end
otherwise if it's already gray, you don't need to call rgb2gray(). Then threshold
binaryImage = grayImage >= 200;
Then count
numberOfWhitePixels = sum(binaryImage(:));
Note: MATLAB uses the American spelling of gray, not the English spelling of grey.
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Upeka Somaratne
le 2 Avr 2018
How can I get the pixel coordinates of the pixels which have intensity value greater than 200? (in matlab)
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