inside advanced edge detection

[gallasi]

Hi all,

I need to understand how edge detection works to measure parts in direct light (with reflections on the surface).
It is clear to me the use of various filters such as sobel or canny but the edges found are not correct for a measurement.
If instead I use advanced edge detection the measurement is correct... what is done inside? is it possible to recreate an "open" program that does the same thing?

Thanks, BR.

AG