plucky (3) get_image_channel_order.3clc.gz
NAME
get_image_channel_order - Return the image channel data order.
int get_image_channel_order(image1d_t image);
int get_image_channel_order(image1d_buffer_t image);
int get_image_channel_order(image2d_t image);
int get_image_channel_order(image3d_t image);
int get_image_channel_order(image1d_array_t image);
int get_image_channel_order(image2d_array_t image);
DESCRIPTION
Return the image channel order. Valid values are:
CLK_A
CLK_R
CLK_Rx
CLK_RG
CLK_RGx
CLK_RA
CLK_RGB
CLK_RGBx
CLK_RGBA
CLK_ARGB
CLK_BGRA
CLK_INTENSITY
CLK_LUMINANCE
NOTES
The values returned by get_image_channel_order as shown above with the CLK_ prefixes correspond to the
CL_ prefixes used to describe the image channel order and data type in the table of supported names and
values in clCreateSubBuffer(3clc) and list of supported Image Channel Order Values for
clCreateImage(3clc). For example, both CL_UNORM_INT8 and CLK_UNORM_INT8 refer to an image channel data
type that is an unnormalized unsigned 8-bit integer.
The following table describes the mapping of the number of channels of an image element to the
appropriate components in the float4, int4 or uint4 vector data type for the color values returned by
read_image{f|i|ui} or supplied to write_image{f|i|ui}. The unmapped components will be set to 0.0 for
red, green and blue channels and will be set to 1.0 for the alpha channel.
┌──────────────────────────┬───────────────────────────────┐
│ Channel Order │ float4, int4 or unsigned int4 │
│ │ components of channel data │
├──────────────────────────┼───────────────────────────────┤
│ CL_R, CL_Rx │ (r, 0.0, 0.0, 1.0) │
├──────────────────────────┼───────────────────────────────┤
│ CL_A │ (0.0, 0.0, 0.0, a) │
├──────────────────────────┼───────────────────────────────┤
│ CL_RG, CL_RGx │ (r, g, 0.0, 1.0) │
├──────────────────────────┼───────────────────────────────┤
│ CL_RA │ (r, 0.0, 0.0, a) │
├──────────────────────────┼───────────────────────────────┤
│ CL_RGB, CL_RGBx │ (r, g, b, 1.0) │
├──────────────────────────┼───────────────────────────────┤
│CL_RGBA, CL_BGRA, CL_ARGB │ (r, g, b, a) │
├──────────────────────────┼───────────────────────────────┤
│ CL_INTENSITY │ (I, I, I, I) │
├──────────────────────────┼───────────────────────────────┤
│ CL_LUMINANCE │ (L, L, L, 1.0) │
└──────────────────────────┴───────────────────────────────┘
A kernel that uses a sampler with the CL_ADDRESS_CLAMP addressing mode with multiple images may result in
additional samplers being used internally by an implementation. If the same sampler is used with multiple
images called via read_imagef2d(3clc), then it is possible that an implementation may need to allocate an
additional sampler to handle the different border color values that may be needed depending on the image
formats being used. These implementation allocated samplers will count against the maximum sampler values
supported by the device and given by CL_DEVICE_MAX_SAMPLERS. Enqueuing a kernel that requires more
samplers than the implementation can support will result in a CL_OUT_OF_RESOURCES error being returned.
SPECIFICATION
OpenCL Specification[1]
SEE ALSO
imageFunctions(3clc)
AUTHORS
The Khronos Group
COPYRIGHT
Copyright © 2007-2011 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 292, section 6.12.14 - Image Read and Write Functions