extract boundaries of images

Hi everyone, I work on breast thermal image.I want separate lower boundaries breast of this images.befor use of parabola Hough transform but I want use another robust approch.would it be possible for direct me or introduce valide source to me or anything else?

Answer 1

[Nitin]

did you try to use edge detection techniques such as canny or sobel?

Also, I would give morphological operations a try to see ...

[fatemeh]

yes, it's require using of canny for detect edge but for extract Accurate lower boundary breast has need to use of a robust technique.