function [I_1bis,I_2bis,I_3bis,I_4bis]=SEPARATION_2seuils(I_1,I_2,seuil1,seuil2) 
[M,N]= size(I_1); T_1 = sign(I_1-seuil2*I_2); T_2 = sign(seuil1*I_2-I_1); 
T_3 = T_1.*T_2; 
I_4bis = max(I_1.*T_1, zeros(M,N));
I_1bis = max(I_2.*T_2, zeros(M,N)); 
I_2bis = max(I_2.*T_3, zeros(M,N)); 
I_3bis = max(I_1.*T_3, zeros(M,N));  
end

