NV21转YUV420SP的代码

　　格式不介绍了，看代码：

    public final static void NV21_TO_YUV420SP(int width, int height, byte[] in)
    {
        int pixels = width * height;
        byte s;
        int count = (pixels / 2);
        for (int i = 0; i < count; i += 2)
        {
            s = in[pixels + i];
            in[pixels + i] = in[pixels + i + 1];
            in[pixels + i + 1] = s;
        }
    }