i am new and here is my code and this screenshot is of normal mamogram but i dnt knw how to remove pectoral muscle using this code

    im =input image;
    BW= shrinkWrap(im,'Biggest');

w=immultiply(BW,im);
%Using histogram to adjust the image
I_eq = adapthisteq(w);

%figure,imshow(I_eq);

%Method #1: using a thresholding method.
%Above 200(>), will appear white; Below <200, will appear black
%Remove objects in the image that is less than 250 pixels
thresholdValue = 200;
binaryImage = I_eq > thresholdValue; 
%clear the border
IM_cb = imclearborder(binaryImage);
BW2 = bwareaopen(IM_cb, 250);
BW_filled = imfill(BW2, 'holes');
%figure,imshow(BW_filled);

labeledImage = bwlabel(BW_filled);
measurements = regionprops(labeledImage, 'Area');
% Get all the areas
allAreas = [measurements.Area]; 
[biggestArea, indexOfBiggest] = sort(allAreas, 'descend');
% Extract biggest
biggestBlob = ismember(labeledImage, indexOfBiggest(1));
% Convert to binary

biggestBlob = biggestBlob > 0;

imshow(biggestBlob, []);

[Image Analyst]

Attach your m-file and original gray scale image.

[bushra mughal]

hi here my .m file

[vid]

hello, Im trying to remove pectoral muscle from mammograms using seeded region growing using the following function http://fr.mathworks.com/matlabcentral/fileexchange/35269-simple-single-seeded-region-growing but the pectoral muscle is not removed instead the inner image becomes black and white background. Please help.