I want to segmentation this image

I have a picture, where the area to be processed is the eye area, so that the black background. I've tried using mat2gray, but less satisfactory results obtained, because the eye area that I want is the original image. but the results I got, red eye area. please help. thanks in advance.

Answer 1

[Image Analyst]

Try something like this:

darkAreas = redChannelImage < 100;
withinFaceOnly = imclearborder(darkAreas);

Answer 2

[Lidank Abiel]

thank you Image Analyst :)

[Image Analyst]

You're welcome. Go ahead and mark it as "Answered".