Get the FoVs of two cameras , are , , respectively. and are the sets
 of the four vertices of and , that is, .
and are the sets of the four edges of and , that is, ,
;
  Initialize the vertex set , the point of intersection of two edges ;
  for   = 1 to 4  do
   if   in   then
     ;
   end
   if   in   then
     ;
   end
   for   = 1 to 4  do
   ;
  if     then
    ;
  end
end
  end
= Sort( );
  The polygon P constructed by vertex set is the intersection polygon of and ;
  return   , .
Algorithm 1: Correlation coefficient calculation.