1 clear all;
 2 close all;
 3 clc;
 4 
 5 img = imread('lena.jpg');
 6 
 7 [m,n,d]=size(img);
 8 I=reshape(img,[],d);   
 9 
10 R=1;
11 x=zeros(m*n,1);
12 y=zeros(m*n,1);
13 z=zeros(m*n,1);
14 num = 0;
15 
16 %做个球。。。
17 for j=-pi/2:pi/n:pi/2-pi/n   
18     for i=0:2*pi/m:2*pi-2*pi/m
19         
20         num=num+1;
21         x(num) = R.*cos(j).*cos(i);
22         y(num) = R.*sin(j).*cos(i);
23         z(num) = R.*sin(i);
24         
25     end
26 end
27 
28 pcshow([x y z],[I I I]);    %如果是彩色图：pcshow([x y z],I);