How to ideally erode this line?

Hi

See attached image.

Imagine, it is a line of a contour. I need to erode it to a point to be a nice clear curve with no bumps and lumps.

Can you suggest a nice imerode () value?

Thanks

[Stelios Fanourakis]

It should also be a thin line of 1 pixel width maximum like the one I attach here