How extract skull by morphological opening operation ?

How to make a morphological opening operation to extract the skull like this:

Answer 1

[hmi amid]

Hi,

You should read a bit about morphological operations to help you understand this. This is an example of code you can use.

A=imread('image.png');
A=A(:,:,1); % Make it grayscale
BW=A>50;    % Thresholding at gray level of 50
disk_radius=2; % radius of the structure element in pixels (you can change that)
se = strel('disk',disk_radius); % Create a structure element shaped like a disk with a given radius
res = imopen(BW,se); % Morphological opening operation
output = uint8(double(res).*double(A)); % This operation takes all pixels of A where res is equal to 1
imshow(output)

Amid.

[marwa za]

Yes I already use the imopen function but it does not give a good result for extraction of the skull

[hmi amid]

You should adapt your disk_radius. In my case I had a very small example (it was the example you gave in the question and it had a small size). Try bigger disk radius, it would probably work. And also, you can change the shape, make it a square for example like this

se = strel('square',square_size);

Amid.