perimeter_new/initial_tign.m

   1 function [tign,fire_mask_out,fire_mask_in]=initial_tign(fire_area,time_now,max_time)
   2 % in:
   3 %   fire_area  1 inside and on perimeter
   4 %   time       the time of the perimeter
   5 %   dir        1 going outside, -1 inside
   6 % out:
   7 %   tign=time_now on perimeter (in fire area, with neighbor who is not)
   8 %       =time_now+max_time outside fire_area
   9 %       =time_now-max_time inside fire_area
  10 %   fire_mask_out
  11 %   fire_mask_in
  12
  13 [m,n]=size(fire_area);
  14 fire_area=fire_area>0;
  15 tign=zeros(m,n);
  16 tign(fire_area)=time_now-max_time;
  17 tign(~fire_area)=time_now+max_time;
  18 fire_area_ext=true(m+2,n+2);
  19 fire_area_ext(2:m+1,2:n+1)=fire_area;
  20 fire_mask_in=fire_area;
  21 fire_mask_out=~fire_area;
  22 for i=1:m
  23     for j=1:n
  24         % neigh=fire_area_ext(i:i+2,j:j+2);
  25         if fire_area(i,j) & ~(...
  26                 fire_area_ext(i+1,j) & fire_area_ext(i+1,j+2) & ...
  27                 fire_area_ext(i,j+1) & fire_area_ext(i+2,j+1) )
  28                 tign(i,j)=time_now;
  29                 fire_mask_out(i,j)=true;
  30                 fire_mask_in(i,j)=true;
  31         end
  32     end
  33 end
  34 end