读取图像
read_imagef (2D) : https://www.khronos.org/registry/OpenCL/sdk/2.0/docs/man/xhtml/read_imagef2d.html
read_imagef (3D) :https://www.khronos.org/registry/OpenCL/sdk/1.2/docs/man/xhtml/read_imagef3d.html
写图像函数
https://www.khronos.org/registry/OpenCL/sdk/2.0/docs/man/xhtml/write_image2d.html
3D 需添加:
#pragma OPENCL EXTENSION cl_khr_3d_image_writes: enable