您好,您这样:
A=imread('D:\lena.BMP');
A=rgb2gray(A);
for k=1:90
for x=1:131
for y=1:131
x1=x+y;
y1=x+2*y;
if x1>131
x1=mod(x1,131);
end
if y1>131
y1=mod(y1,131);
end
if x1==0
x1=131;
end
if y1==0
y1=131;
end
A1(x1,y1)=A(x,y);
end
end
A=A1;
end
imshow(A1);