Obtaining the largest object in an image

Say that I have an image with a big object, and then small objects spread apart.

How can I retrieve only that big object?

I think we can use "bwconncomp"?

But, how exactly can we do that here?

Thanks.

Answer 1

[Image Analyst]

I thought I've given this to you before. Oh well, maybe it was someone else. I've posted it lots and lots of times. Here it is again. The function inside the attached demo will let you extract the N largest or smallest blobs in a binary image.

[med-sweng]

Thanks for the nice answer. For the final result, if I want to imwrite it, would it be doing the following?

imwrite(binaryImage, 'FinalResult.png');

after:

binaryImage = biggestBlob > 0;

[Image Analyst]

Yes. But you might want to multiply it by 255 first so you can see it without scaling, like if you want a nice thumbnail image in your operating system

imwrite(uint8(255*binaryImage), filename);