我正在尝试使用指针而不是2D图像对象缓冲区来读取图像对象
img_fmt.image_channel_order = CL_R;
img_fmt.image_channel_data_type = CL_UNORM_INT8;
__kernel void test(__read_only image2d_t in, __write_only image2d_t out)
{
float *p;
void *temp;
temp = (void *)∈
p=temp;
if(get_global_id(0) == 10)
printf("%f",*p);
}
然而，当我得到这个的印刷品时，我看到所有的值都是零。 我想这样做
1）找出其发生的原因？
2）如果以上工作我想在指针p上使用vload16一次获得16个像素？我不认为它可以从图像对象的地址获得16个像素，但我想看看该地址的内存中有什么？
当我在每个工作项ID上打印in的地址时，我看到了一件有趣的事情。使用以下代码：
__kernel void test(__read_only image2d_t in, __write_only image2d_t out)
{
float *p;
void *temp;
temp = (void *)∈
if(get_global_id(0) < 50)
printf("%p",temp);
}
0x500000000 row no 0 col no 0 0x500004000 row no 0 col no 4 0x500008000 row no 0 col no 8 0x50000C000 row no 0 col no 12 0x500000080 row no 0 col no 16 0x500004080 row no 0 col no 20
0x500000008 row no 0 col no 1 0x500004008 row no 0 col no 5 0x500008008 row no 0 col no 9 0x50000C008 row no 0 col no 13 0x500000088 row no 0 col no 17 0x500004088 row no 0 col no 21
0x500000010 row no 0 col no 2 0x500004010 row no 0 col no 6 0x500008010 row no 0 col no 10 0x50000C010 row no 0 col no 14 0x500000090 row no 0 col no 18 0x500004090 row no 0 col no 22
0x500000018 row no 0 col no 3 0x500004018 row no 0 col no 7 0x500008018 row no 0 col no 11 0x50000C018 row no 0 col no 15 0x500000098 row no 0 col no 19 0x500004098 row no 0 col no 23
0x500000020 row no 1 col no 0 0x500004020 row no 1 col no 4 0x500008020 row no 1 col no 8 0x50000C020 row no 1 col no 12 0x5000000A0 row no 1 col no 16 0x5000040A0 row no 1 col no 20
0x500000028 row no 1 col no 1 0x500004028 row no 1 col no 5 0x500008028 row no 1 col no 9 0x50000C028 row no 1 col no 13 0x5000000A8 row no 1 col no 17 0x5000040A8 row no 1 col no 21
0x500000030 row no 1 col no 2 0x500004030 row no 1 col no 6 0x500008030 row no 1 col no 10 0x50000C030 row no 1 col no 14 0x5000000B0 row no 1 col no 18 0x5000040B0 row no 1 col no 22
0x500000038 row no 1 col no 3 0x500004038 row no 1 col no 7 0x500008038 row no 1 col no 11 0x50000C038 row no 1 col no 15 0x5000000B8 row no 1 col no 19 0x5000040B8 row no 1 col no 23
0x500000040 row no 2 col no 0 0x500004040 row no 2 col no 4 0x500008040 row no 2 col no 8 0x50000C040 row no 2 col no 12 0x5000000C0 row no 2 col no 16 0x5000040C0 row no 2 col no 20
0x500000048 row no 2 col no 1 0x500004048 row no 2 col no 5 0x500008048 row no 2 col no 9 0x50000C048 row no 2 col no 13 0x5000000C8 row no 2 col no 17 0x5000040C8 row no 2 col no 21
0x500000050 row no 2 col no 2 0x500004050 row no 2 col no 6 0x500008050 row no 2 col no 10 0x50000C050 row no 2 col no 14 0x5000000D0 row no 2 col no 18 0x5000040D0 row no 2 col no 22
0x500000058 row no 2 col no 3 0x500004058 row no 2 col no 7 0x500008058 row no 2 col no 11 0x50000C058 row no 2 col no 15 0x5000000D8 row no 2 col no 19 0x5000040D8 row no 2 col no 23
0x500000060 row no 3 col no 0 0x500004060 row no 3 col no 4 0x500008060 row no 3 col no 8 0x50000C060 row no 3 col no 12 0x5000000E0 row no 3 col no 16 0x5000040E0 row no 3 col no 20
0x500000068 row no 3 col no 1 0x500004068 row no 3 col no 5 0x500008068 row no 3 col no 9 0x50000C068 row no 3 col no 13 0x5000000E8 row no 3 col no 17 0x5000040E8 row no 3 col no 21
0x500000070 row no 3 col no 2 0x500004070 row no 3 col no 6 0x500008070 row no 3 col no 10 0x50000C070 row no 3 col no 14 0x5000000F0 row no 3 col no 18 0x5000040F0 row no 3 col no 22
0x500000078 row no 3 col no 3 0x500004078 row no 3 col no 7 0x500008078 row no 3 col no 11 0x50000C078 row no 3 col no 15 0x5000000F8 row no 3 col no 19 0x5000040F8 row no 3 col no 23
每个4x4磁贴存储在连续的地址空间中。实际上存在用于存储瓦片的模式像第0和第4个4x4块在内存中也是连续的。
我无法连接所有东西。如果有人能提供帮助，那将是美好的。
答案 0 :(得分：0)
你根本无法做你想做的事; image2d_t类型不是指针。如果您的特定实现恰好让您以某种方式使用它看起来像图像数据，它只是实现的工件，您不能期望它是可移植的，甚至可以使用下一个驱动程序版本。
也许你想要的是你可以作为缓冲区或图像访问的设备内存。如果是，请使用cl_khr_image2d_from_buffer扩展名。