cl_image_format
cl_image_format
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cl_image_format The image format descriptor structure is defined as:

##

typedef struct _cl_image_format { cl_channel_order image_channel_order; cl_channel_type image_channel_data_type; } cl_image_format;

## Members

image_channel_order
  Specifies the number of channels and the channel layout i.e. the memory layout in which channels are stored in the image. Valid values are described in the table below.

  Format | Description
  --- | ---
  CL_R, CL_Rx, or CL_A |
  CL_INTENSITY | This format can only be used if channel data type = CL_UNORM_INT8, CL_UNORM_INT16, CL_SNORM_INT8, CL_SNORM_INT16, CL_HALF_FLOAT, or CL_FLOAT.
  CL_LUMINANCE | This format can only be used if channel data type = CL_UNORM_INT8, CL_UNORM_INT16, CL_SNORM_INT8, CL_SNORM_INT16, CL_HALF_FLOAT, or CL_FLOAT.
  CL_RG, CL_RGx, or CL_RA |
  CL_RGB or CL_RGBx | This format can only be used if channel data type = CL_UNORM_SHORT_565, CL_UNORM_SHORT_555 or CL_UNORM_INT101010.
  CL_RGBA |
  CL_ARGB, CL_BGRA. | This format can only be used if channel data type = CL_UNORM_INT8, CL_SNORM_INT8, CL_SIGNED_INT8 or CL_UNSIGNED_INT8.

image_channel_data_type
  Describes the size of the channel data type. The number of bits per element determined by the `image_channel_data_type` and `image_channel_order` must be a power of two. The list of supported values is described in the table below.

  Image Channel Data Type | Description
  --- | ---
  CL_SNORM_INT8 | Each channel component is a normalized signed 8-bit integer value.
  CL_SNORM_INT16 | Each channel component is a normalized signed 16-bit integer value.
  CL_UNORM_INT8 | Each channel component is a normalized unsigned 8-bit integer value.
  CL_UNORM_INT16 | Each channel component is a normalized unsigned 16-bit integer value.
  CL_UNORM_SHORT_565 | Represents a normalized 5-6-5 3-channel RGB image. The channel order must be CL_RGB or CL_RGBx.
  CL_UNORM_SHORT_555 | Represents a normalized x-5-5-5 4-channel xRGB image. The channel order must be CL_RGB or CL_RGBx.
  CL_UNORM_INT_101010 | Represents a normalized x-10-10-10 4-channel xRGB image. The channel order must be CL_RGB or CL_RGBx.
  CL_SIGNED_INT8 | Each channel component is an unnormalized signed 8-bit integer value.
  CL_SIGNED_INT16 | Each channel component is an unnormalized signed 16-bit integer value.
  CL_SIGNED_INT32 | Each channel component is an unnormalized signed 32-bit integer value.
  CL_UNSIGNED_INT8 | Each channel component is an unnormalized unsigned 8-bit integer value.
  CL_UNSIGNED_INT16 | Each channel component is an unnormalized unsigned 16-bit integer value.
  CL_UNSIGNED_INT32 | Each channel component is an unnormalized unsigned 32-bit integer value.
  CL_HALF_FLOAT | Each channel component is a 16-bit half-float value.
  CL_FLOAT | Each channel component is a single precision floating-point value.

## Description

For example, to specify a normalized unsigned 8-bit / channel RGBA image:

              image_channel_order = CL_RGBA
              image_channel_data_type = CL_UNORM_INT8

`image_channel_data_type` values of `CL_UNORM_SHORT_565`, `CL_UNORM_SHORT_555` and `CL_UNORM_INT_101010` are special cases of packed image formats where the channels of each element are packed into a single unsigned short or unsigned int. For these special packed image formats, the channels are normally packed with the first channel in the most significant bits of the bitfield, and successive channels occupying progressively less significant locations. For `CL_UNORM_SHORT_565`, R is in bits 15:11, G is in bits 10:5 and B is in bits 4:0. For `CL_UNORM_SHORT_555`, bit 15 is undefined, R is in bits 14:10, G in bits 9:5 and B in bits 4:0. For `CL_UNORM_INT_101010`, bits 31:30 are undefined, R is in bits 29:20, G in bits 19:10 and B in bits 9:0.

OpenCL implementations must maintain the minimum precision specified by the number of bits in `image_channel_data_type`. If the image format specified by `image_channel_order`, and `image_channel_data_type` cannot be supported by the OpenCL implementation, then the call to clCreateImage will return a NULL memory object.

## Specification

OpenCL Specification

## Also see

cl_image_desc Image Descriptor, EXTENSION, clGetSupportedImageFormats, clCreateImage

##