curve fitting and then segmentation

Hello, im currently working with breast thermograms. I have detected the edges using canny operator(breast boundary.png). For my next step i want to try a curve fitting algorithm for right and left breast segmentation. The idea is to fit the two curves of the breasts and find a bifurcation point and segment the image. I have attatched an image of what i want to do(img), can someone please tell me how to do it? Thank you in advance.

[KALYAN ACHARJYA]

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