1 void yuvMirror(unsigned char* yuv, int w, int h)
 2 {
 3     int i;
 4     int a, b;
 5 
 6     for (i = 0; i < h; i++)
 7     {
 8         a = i * w;
 9         b = (i + 1) * w - 1;
10         while (a < b)
11         {
12             _swap(yuv[a], yuv[b]);
13             a++; b--;
14         }
15     }
16 
17     int uStartPos = w * h; 
18     for (i = 0; i < h / 2; i++)
19     {
20         a = i * w / 2;
21         b = (i + 1) * w / 2 - 1;
22         while (a < b)
23         {
24             _swap(yuv[a+ uStartPos], yuv[b+ uStartPos]);
25             a++; b--;
26         }
27     }
28 
29     int vStartPos = w * h / 4 * 5;
30     for (i = 0; i < h / 2; i++)
31     {
32         a = i * w / 2;
33         b = (i + 1) * w / 2 - 1;
34         while (a < b)
35         {
36             _swap(yuv[a+ vStartPos], yuv[b+ vStartPos]);
37             a++; b--;
38         }
39     }
40 
41 }

1 void _swap(unsigned char& a, unsigned char& b)
2 {
3 　　a ^= b;
4 　　b ^= a;
5 　　a ^= b;
6 }