x=avsread('huber/phtmtbl.fld');
image(256-x'/0.13*256); hold on;
[xxm,yym]=meshgrid(1:128,1:128);
lset=sqrt((xxm-50).^2*1.5+(yym-62).^2/2)-18;
[level0,level0size]=contour0(lset);
for j=1:level0size,plot(level0(j,2),level0(j,1),'r.');end;

lset=sqrt((xxm-90).^2*1.5+(yym-62).^2/2)-18;
[level0,level0size]=contour0(lset);
for j=1:level0size,plot(level0(j,2),level0(j,1),'r.');end;

lset=sqrt((xxm-67).^2+(yym-90).^2)-3;
[level0,level0size]=contour0(lset);
for j=1:level0size,plot(level0(j,2),level0(j,1),'y.');end;

lset=sqrt((xxm-67).^2/2+(yym-66).^2)-40;
[level0,level0size]=contour0(lset);
for j=1:level0size,plot(level0(j,2),level0(j,1),'r.');end; hold off;
axis image; axis off
