NAME¶
imageDescriptor - The image descriptor structure describes the
type and dimensions of the image or image array and is defined as:
| typedef struct _cl_image_desc { cl_mem_object_type image_type; size_t
image_width; size_t image_height; size_t image_depth; size_t
image_array_size; size_t image_row_pitch; size_t image_slice_pitch;
cl_uint num_mip_levels; cl_uint num_samples; cl_mem buffer; }
cl_image_desc; |
MEMBERS¶
image_type
Describes the image type and must be either
CL_MEM_OBJECT_IMAGE1D, CL_MEM_OBJECT_IMAGE1D_BUFFER,
CL_MEM_OBJECT_IMAGE1D_ARRAY, CL_MEM_OBJECT_IMAGE2D,
CL_MEM_OBJECT_IMAGE2D_ARRAY, or CL_MEM_OBJECT_IMAGE3D.
image_width
The width of the image in pixels. For a 2D image and
image array, the image width must be ≤
CL_DEVICE_IMAGE2D_MAX_WIDTH. For a 3D image, the image width must be
≤ CL_DEVICE_IMAGE3D_MAX_WIDTH. For a 1D image buffer, the image
width must be ≤ CL_DEVICE_IMAGE_MAX_BUFFER_SIZE. For a 1D image
and 1D image array, the image width must be ≤
CL_DEVICE_IMAGE2D_MAX_WIDTH.
image_height
The height of the image in pixels. This is only used if
the image is a 2D, 3D or 2D image array. For a 2D image or image array, the
image height must be ≤ CL_DEVICE_IMAGE2D_MAX_HEIGHT. For a 3D
image, the image height must be ≤
CL_DEVICE_IMAGE3D_MAX_HEIGHT.
image_depth
The depth of the image in pixels. This is only used if
the image is a 3D image and must be a value ≥ 1 and ≤
CL_DEVICE_IMAGE3D_MAX_DEPTH.
image_array_size
The number of images in the image array. This is only
used if the image is a 1D or 2D image array. The values for
image_array_size, if specified, must be a value ≥ 1 and ≤
CL_DEVICE_IMAGE_MAX_ARRAY_SIZE.
Note that reading and writing 2D image arrays from a kernel with
image_array_size = 1 may be lower performance than 2D images.
image_row_pitch
The scan-line pitch in bytes. This must be 0 if
host_ptr is NULL and can be either 0 or ≥ image_width * size of
element in bytes if host_ptr is not NULL. If host_ptr is not
NULL and image_row_pitch = 0, image_row_pitch is calculated as
image_width * size of element in bytes. If image_row_pitch is
not 0, it must be a multiple of the image element size in bytes.
image_slice_pitch
The size in bytes of each 2D slice in the 3D image or the
size in bytes of each image in a 1D or 2D image array. This must be 0 if
host_ptr is NULL. If host_ptr is not NULL,
image_slice_pitch can be either 0 or ≥ image_row_pitch *
image_height for a 2D image array or 3D image and can be either 0 or
≥ image_row_pitch for a 1D image array. If host_ptr is
not NULL and image_slice_pitch = 0, image_slice_pitch is
calculated as image_row_pitch * image_height for a 2D image
array or 3D image and image_row_pitch for a 1D image array. If
image_slice_pitch is not 0, it must be a multiple of the
image_row_pitch.
num_mip_level, num_samples
, Must be 0.
buffer
Refers to a valid buffer memory object if
image_type is CL_MEM_OBJECT_IMAGE1D_BUFFER. Otherwise it must be
NULL. For a 1D image buffer object, the image pixels are taken from the buffer
object's data store. When the contents of a buffer object's data store are
modified, those changes are reflected in the contents of the 1D image buffer
object and vice-versa at corresponding sychronization points. The
image_width * size of element in bytes must be ≤ size of buffer
object data store.
NOTE¶
Concurrent reading from, writing to and copying between both a
buffer object and 1D image buffer object associated with the buffer object
is undefined. Only reading from both a buffer object and 1D image buffer
object associated with the buffer object is defined.
SPECIFICATION¶
OpenCL Specification[1]
SEE ALSO¶
cl_image_format(3clc)
AUTHORS¶
The Khronos Group
COPYRIGHT¶
Copyright © 2007-2010 The Khronos Group Inc.
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to the
condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials.
NOTES¶
- 1.
- OpenCL Specification
page 95, section 5.3.1.2 - Image Descriptor
