Tracking a countour and the inside of an image

Like the coding challenge based on tracking the border of a text, I'm trying to achieve something similar by using an image. I want to get a final result that is something like this http://www.citakrugs.ca. do anyone have any idea on how to do that?

The issue mentions tracking the border and inside of an image, with a reference to an external example, but names no files, entry points, or tests. First clarify the intended behavior and whether this is a topic suggestion rather than a repository change; completion criteria are not defined.

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