how to find original intensity at retina image

i want to find the intesity at original image by compare at image that i get. example: my original image is retina image and my second image is image from erosion operation.. then i want to compare the intensity at original image with my erosion image.

[Image Analyst]

What does "compare" mean to you? Do you simply want to subtract the images? I have no idea what result you would like to have.

Answer 1

[Walter Roberson]

Selected_Intensities = Intensity_Image( logical(Erosion_Image) );

The result will be a vector of intensities of points that were non-zero in the erosion image.

[Farah Nadiah]

how can i remove the hemorrhages intensity.. hemorrhages is a dot in red color but large in size.. i just want microaneurysms only.. microaneurysms is dot in small size and red in color.. if i use this matlab code can u modify a little bit :)

%Original Image
I = imread ('image100.png');
A = imread ('erosion.jpg');
if (A = 0)
  S = ( i want this is intensity for my original image)
else
  S = (i dont know to put what)
end

and i want the image

imshow(S);

this is my original image

this is my erosion image

[Walter Roberson]

S = I .* repmat(A, 1, 1, 3);

Answer 2

[Image Analyst]

You can use beareaopen() to distinguish between larger hemorrhages and smaller microaneurysms.

sizeThreshold = 100; % Whatever size you want.
hemorrhages = bwareaopen(binaryImage, sizeThreshold); % Keep larger blobs.
microaneurysms = xor(binaryImage, hemorrhages); % Keep small blobs.