function y = recale(x)
%        y = recale(x)
% recalage de x entre 0 et 255
% y = a*x + b
%------------------------------------------------

[nl,nc] = size(x);
m = min(min(x));
M = max(max(x));
c = [m 1; M 1]\[0;255];
a = c(1); b = c(2);
y = a*x+b;

