You can use particle swarm optimization.

Thank u mam @Sheela Sobana Rani..

I have not tried that for edge detection yet, need to look into it..

Thank u so much

Thank u sir @Joachim Pimiskern..!!

Madam, You can also use cellular automata for edge detection.

Some articles are:

1. https://link.springer.com/chapter/10.1007%2F978-3-319-06431-4_5#page-1

2. http://ieeexplore.ieee.org/abstract/document/1380502/

3. http://www.ijcaonline.org/archives/volume118/number17/20837-3550

etc

Thank u so much sir..I shall definitely have a look into all the articles that u ve suggested @Chinmoy Kar