how can i fill the region inside the bones in an image ?

<<[fn,pn] = uigetfile({'*.JPG','Image files'}, 'Select an image'); image = imread(fullfile(pn,fn));

image1 = rgb2gray(image); background = imopen(image1,strel('disk',25)); Ip = imsubtract(image1,background); imtool(Ip,[]);

/matlabcentral/answers/uploaded_files/4861/out1.JPG>>

i subtract an image background from an x ray image. i want to fill the extracted image bones as white color. which filling is suitable if i know the location of each bone. any other method by clicking any location to fill those region surrounded by that bone.?

I want the bones color as white. I apply some threshold method. Then only i understand inside that bones also some black color is there. By using any mouse click or automatic , can i fill all bones as white color?