Open the picture you want to work with and draw a shape with the Lasso-tool

Select inverse and press delete.
Now go to Filter/Pixelate and chose crystallize and use the cellsize 3. Do this twice.
Deselect and click with the MagicWand tool outside the  picture and select inverse again.

Go to Select/modify/border and set it to 4 pixels. then go to Select/Feather and set it to 2 pixels. Fill the border with 50% black and youВґre done.