creating a polygon border from binary file

Added by Katarina 11 days ago

I have an xyz geographical file where x is lon,y is lat and z values are 1 and 0. I turned it into a grid using xyz2grd.

The areas where z=1 are my interest areas. I would like to have polygon files that contain only the points on the border of each interest area. So not all the points where values z=1 (not sites inside the interest area), only those that are on the edge of the areas. Is it possible to do that?