How to mask the inner region of this Binary Image? Can anyone give some idea?

This is Abdomen image(img1.jpg) . The Inner region should be completely black. if we use imfill the entire region becomes black as there is a gap in it.

Edge fill cannot be used as the shape of inner region varies.

I need to get image like this(img2.jpg)

The original image(newImg.jpg)

Answer 1

[KALYAN ACHARJYA]

I would suggest you the slightly improved on thresholding (segmentation results), which leads great help to disconnect the black pixel link (as result shown)

se=strel('disk',5);
result=imerode(test_image,se);
largest_blob=bwareafilt(result,1,'largest');
result=imdilate(largest_blob,se);
figure,imshow(result);

Hope it Helps!

[SASIREKHA DURAISAMY]

Thank you for your suggestion sir.

As you said i modified the threshold. I am getting the image as shown.

But my aim is to calculate the Fat. I need to calculate the white area inside the inner mask and also outside separately. On doing the above there will be changes in the fat values.(eg: Inner organ touches the outer skin layer in the second dilated image and also gap regions created its own shape which differs from the original Image).

Sir any idea you have to solve this problem. If so pls share.

[KALYAN ACHARJYA]

"On doing the above there will be changes in the fat values.(eg: Inner organ touches the outer skin layer in the second dilated image and also gap regions created its own shape which differs from the original Image)".

Thats why, I asked to adjust accordingly, so that the link should be broken and rest are as same after morpho operations