Morphological Transformation, remove border border of a closed image

D
Daniel Tofino · Feb 24, 2022 · 2K views
Question
Hello   I need to remove the upper border (red highligth) of this binarized image without affecting the bottom section, i haven't been able to figure out exactly which functions of the Image Processing Toolbox could help me.  
Expert Answer
Profile picture of Prashant Kumar
Prashant Kumar PhD Expert
Answered Aug 13, 2026

Using morphological operations and connected components algorithm, the problem can be solved with the minor loss of bottom pixels.For example:

 

a=imread('imag.jpeg');
figure;imshow(a)
se = strel('line',8,90);
eroded = imerode(a,se);
b=logical(eroded);
st=regionprops('Table',b(:,:,1),'Area');
m=maxk(st.Area,2);
biggest = bwareafilt(b(:,:,1),[m(2) m(1)]);
figure;imshow(biggest)
dil=imdilate(biggest,se);
figure;imshow(dil)

The above code results in the below image. You can try with some other parameters of morphological processing and check if it will be more clear.

Have a different question? Ask here

Get a Free Consultation or a Sample Assignment Review!