detection/sfire_simple_mat.m

   1 function t1=sfire_simple_mat(rr,t0,mask,ncycles)
   2 % in:
   3 % rr            structure with 2d fields r11...r33
   4 % t0            starting tign
   5 % mask          if not 0, update
   6 % out:
   7 % t1            updated ignition times
   8 %
   9 persistent r11 r12 r13 r21 r23 r31 r32 r33
  10
  11 if ncycles<=0,
  12     r11=rr.r11;
  13     r12=rr.r12;
  14     r13=rr.r13;
  15     r21=rr.r21;
  16     r23=rr.r23;
  17     r31=rr.r31;
  18     r32=rr.r32;
  19     r33=rr.r33;
  20 else
  21     [m,n]=size(t0);
  22     t1=t0;
  23     for k=1:ncycles,
  24         for j=2:n-1
  25             for i=2:m-1
  26                 if mask(i,j)>0,
  27                 t=inf;
  28                 t=min(t,t0(i-1,j)+r32(i-1,j));
  29                 t=min(t,t0(i+1,j)+r12(i+1,j));
  30                 t=min(t,t0(i,j-1)+r23(i,j-1));
  31                 t=min(t,t0(i,j+1)+r21(i,j+1));
  32                 t=min(t,t0(i-1,j-1)+r33(i-1,j-1));
  33                 t=min(t,t0(i+1,j-1)+r13(i+1,j-1));
  34                 t=min(t,t0(i-1,j+1)+r31(i-1,j+1));
  35                 t=min(t,t0(i+1,j+1)+r11(i+1,j+1));
  36                 t1(i,j)=t;
  37                 end
  38             end
  39         end
  40     end
  41 end
  42