Explain more exactly what "half left and right breasts" means.
Show an image and outline what you want segmented. Do you just want to split the image in half into two images at the center column? Like
midColumn = round(size(grayImage, 2) / 2);
leftHalf = grayImage(:, 1:midColumns);
rightHalf = grayImage(:, midColumn+1:end);
OR, do you want to segment each breast (right one and left one), then chop each one in half vertically or horizontally? Or something else. I have no idea.
But first read this link
