灰度共生矩阵matlab

function T=coocurrence（Image）

Gray=rgb2gray（Image）;
[MN] = size（Gray）;
%为了减少计算量，对原始图像灰度级压缩，将Gray量化成16级
for i = 1:M
    for j = 1:N
        for n = 1:256/16
            if （n-1）*16<=Gray（ij）&Gray（ij）<=（n-1）*16+15
                Gray（ij） = n-1;
            end
        end
    end
end
%计算四个共生矩阵P取距离为1，角度分别为04590135
P = zeros（16164）;
for m = 1:16
    for n = 1:16
        for i = 1:M
            for j = 1:N
                if j                    P（mn1） = P（mn1）+1;
                    P（nm1） = P（mn1）;
                end
                if i>1&j                    P（mn2） = P（mn2）+1;
                    P（nm2） = P（mn2）;
                end
                if i                    P（mn3） = P（mn3）+1;
                    P（nm3） = P（mn3）;
                end
                if i                    P（mn4） = P（mn4）+1;
                    P（nm4） = P（mn4）;
                end
            end
        end
        if m==n
            P（