Hello,
The following sample code will extract the segment of image that you could use for classification.
Here I assumed you wanted to threshold an RGB image and you are using grey scale intensity of the RGB image for Otsu’s thresholding.
colorImage= imread('peppers.png');
grayVersion = rgb2gray(colorImage);
thresholded = imbinarize(grayVersion); %Does thresholding by using Otsu’s method.
thresholded(:,:,2) = thresholded;
thresholded(:,:,3) = thresholded(:,:,1);
colorImage(thresholded == 0) = 0; %Extract the color image with the threshold region alone
