How to compare color images
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I have used the coding below but it cannot read my rgb values. can someone helps me.
% Read in the Base Image
imgblue = imread('Blue.jpg');
blue = imcrop(imgblue,[60 72 580 300]);
figure, imshow(blue), title('Blue Image'), impixelinfo;
Rb = blue(:,:,1);
Gb = blue(:,:,2);
Bb = blue(:,:,3);
imggreen = imread('Green.jpg');
green = imcrop(imggreen,[60 72 580 300]);
figure, imshow(green), title('Green Image'), impixelinfo;
Rg = green(:,:,1);
Gg = green(:,:,2);
Bg = green(:,:,3);
imgyellow = imread('Yellow.jpg');
yellow = imcrop(imgyellow,[60 72 580 300]);
figure, imshow(yellow), title('Yellow Image'), impixelinfo;
Ry = yellow(:,:,1);
Gy = yellow(:,:,2);
By = yellow(:,:,3);
%figure, imshow(Ryellow), impixelinfo;
% Read in the Input Image
imgtest = imread('Test.jpg');
test = imcrop(imgtest,[60 72 580 300]);
figure, imshow(test), title('Test Image'), impixelinfo;
Rt = test(:,:,1);
Gt = test(:,:,2);
Bt = test(:,:,3);
if (Rt==Rb)&&(Gt==Gb)&&(Bt==Bb)
h = msgbox('The colour image is BLUE','Blue');
else if (Rt==Rg)&&(Gt==Gg)&&(Bt==Bg)
h = msgbox('The colour image is GREEN','Green');
else if (Rt==Ry)&&(Gt==Gy)&&(Bt==By)
h = msgbox('The colour image is YELLOW','Yellow');
else
h = msgbox('Operation Completed','Unknown');
end
end
end
4 Comments
Image Analyst
on 14 Dec 2017
Exactly what does "cannot read my rgb values" mean? Does imread() work or does it throw an error?
Answers (2)
Image Analyst
on 14 Dec 2017
Use isequal():
if isequal(Rt, Rb) && isequal(Gt, Gb) && isequal(Bt, Bb)
h = msgbox('The colour image is BLUE', 'Blue');
elseif isequal(Rt, Rg) && isequal(Gt, Gg) && isequal(Bt, Bg)
h = msgbox('The colour image is GREEN', 'Green');
elseif isequal(Rt, Ry) && isequal(Gt, Gy) && isequal(Bt, By)
h = msgbox('The colour image is YELLOW', 'Yellow');
else
h = msgbox('The colour is unknown','Unknown');
end
2 Comments
Image Analyst
on 15 Dec 2017
Edited: Image Analyst
on 15 Dec 2017
They're not exactly equal. The test image was red and the reference colors were cyan, yellow, and green.
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