decry_scramb.asv

function [K] = decry_scramb(T,X)
    [M,N,k]=size(T);
    m = M;
    n = N; 
    l = min(floor(sqrt(m)),floor(sqrt(n)));
    L=l*l;
    [A,IA] = sort(X(1:(L)));                  %sorting by rows
    [B,IB] = sort(X(L+1:2*L));
    [Y,IY] = sort(X(2*L+1:3*L));
    [Z,IZ] = sort(X(3*L+1:4*L)); 
    O = [L,L];
    Q = [L,L]; 
        for j = 1:L
            for i = 1:L
                m = (mod((i+IB(j)-1),L))+1;
                n = (mod((i+IZ(j)-1),L))+1;
                O(i,j) = IA(m);
                Q(i,j) = IY(n);
            end
        end
    for i = 1:L
                for j = 1:L
                    a = O(i,j);
                    b = Q(a,j);
                    m1 = floor(((a-1)/l));
                    n1 = mod((a-1),l);
                    m2 = floor(((b-1)/l))+1;
                    n2 = mod((b-1),l)+1;
                    x = m1*l+m2;
                    y = n1*l+n2;
                    K(i,j) = T(x,y); 
                end
    end