Provided by: opencl-1.2-man-doc_1.0~svn22836-1.1_all 
NAME
clCreateFromDX9MediaSurfaceKHR - Creates an OpenCL image object from a media surface.
cl_mem clCreateFromDX9MediaSurfaceKHR(cl_context context, cl_mem_flags flags,
cl_dx9_media_adapter_type_khr adapter_type,
void *surface_info, cl_uint plane,
cl_int *errcode_ret);
PARAMETERS
context
A valid OpenCL context created from a media adapter.
flags
A bit-field that is used to specify usage information. Refer to the table of allowed
values for flags for clCreateBuffer(3clc). Only CL_MEM_READ_ONLY, CL_MEM_WRITE_ONLY,
and CL_MEM_READ_WRITE values specified in the table of allowed values for flags for
clCreateBuffer(3clc) can be used.
adapter_type
A value from enumeration of supported adapters described in the table of
cl_dx9_media_adapter_type_khr values for clGetDeviceIDsFromDX9MediaAdapterKHR(3clc).
The type of surface_info is determined by the adapter type. The implementation does
not need to support all adapter types. This approach provides flexibility to support
additional adapter types in the future. Supported adapter types are
CL_ADAPTER_D3D9_KHR, CL_ADAPTER_D3D9EX_KHR, and CL_ADAPTER_DXVA_KHR.
If adapter_type is CL_ADAPTER_D3D9_KHR, CL_ADAPTER_D3D9EX_KHR, or CL_ADAPTER_DXVA_KHR,
the surface_info points to the following structure:
For D3D9 surfaces, we need both the handle to the resource and the resource itself to
have a sufficient amount of information to eliminate a copy of the surface for sharing
in cases where this is possible. Elimination of the copy is driver dependent.
shared_handle may be NULL and this may result in sub-optimal performance.
surface_info
A pointer to one of the structures defined in the adapter_type description above
passed in as a void *.
plane
The plane of resource to share for planar surface formats. For planar formats, we use
the plane parameter to obtain a handle to thie specific plane (Y, U or V for example).
For nonplanar formats used by media, plane must be 0.
errcode_ret
An appropriate error code. If errcode_ret is NULL, no error code is returned.
NOTES
The width and height of the returned OpenCL 2D image object are determined by the width
and height of the plane of resource. The channel type and order of the returned image
object is determined by the format and plane of resource and are described in tables
9.10.3 and 9.10.4.
This call will increment the internal media surface count on resource. The internal media
surface reference count on resource will be decremented when the OpenCL reference count on
the returned OpenCL memory object drops to zero. DX9 Media Surface Sharing.PP The goal of
this extension is to allow applications to use media surfaces as OpenCL memory objects.
This allows efficient sharing of data between OpenCL and selected adapter APIs (only DX9
for now). If this extension is supported, an OpenCL image object can be created from a
media surface and the OpenCL API can be used to execute kernels that read and/or write
memory objects that are media surfaces. Note that OpenCL memory objects may be created
from the adapter media surface if and only if the OpenCL context has been created from
that adapter.
If this extension is supported by an implementation, the string "cl_khr_media_sharing"
will be present in the CL_PLATFORM_EXTENSIONS or CL_DEVICE_EXTENSIONS string described in
the table of allowed values for param_name for clGetDeviceInfo(3clc).
As currently proposed the interfaces for this extension would be provided in
cl_dx9_media_sharing.h.
This section includes the D3D surface formats that are supported when the adapter type is
one of the Direct 3D lineage . Using a D3D surface format not listed here is an error. To
extend the use of this extension to support media adapters beyond DirectX9 tables similar
to the ones in this section will need to be defined for the surface formats supported by
the new media adapter. All implementations that support this extension are required to
support the NV12 surface format, the other surface formats supported are the same surface
formats that the adapter you are sharing with supports as long as they are listed in the
two tables below.
┌────────────────────────────┬─────────────────────────────────┐
│ FOUR CC code │ CL image format (channel order, │
│ │ channel data type) │
├────────────────────────────┼─────────────────────────────────┤
│FOURCC('N', 'V', '1', '2'), │ CL_R, CL_UNORM_INT8 │
│Plane 0 │ │
├────────────────────────────┼─────────────────────────────────┤
│FOURCC('N', 'V', '1', '2'), │ CL_RG, CL_UNORM_INT8 │
│Plane 1 │ │
├────────────────────────────┼─────────────────────────────────┤
│FOURCC('Y', 'V', '1', '2'), │ CL_R, CL_UNORM_INT8 │
│Plane 0 │ │
├────────────────────────────┼─────────────────────────────────┤
│FOURCC('Y', 'V', '1', '2'), │ CL_R, CL_UNORM_INT8 │
│Plane 1 │ │
├────────────────────────────┼─────────────────────────────────┤
│FOURCC('Y', 'V', '1', '2'), │ CL_R, CL_UNORM_INT8 │
│Plane 2 │ │
└────────────────────────────┴─────────────────────────────────┘
In the table above, NV12 Plane 0 corresponds to the luminance (Y) channel and Plane 1
corresponds to the UV channels. The YV12 Plane 0 corresponds to the Y channel, Plane 1 to
the U channel and Plane 2 to the V channel. Note that the YUV formats map to CL_R and
CL_RG but do not perform any YUV to RGB conversion and vice-versa.
┌─────────────────────┬─────────────────────────────────┐
│ D3D format │ CL image format (channel order, │
│ │ channel data type) │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_R32F │ CL_R, CL_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_R16F │ CL_R, CL_HALF_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_L16 │ CL_R, CL_UNORM_INT16 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_A8 │ CL_A, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_L8 │ CL_R, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_G32R32F │ CL_RG, CL_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_G16R16F │ CL_RG, CL_HALF_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_G16R16 │ CL_RG, CL_UNORM_INT16 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_A8L8 │ CL_RG, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│D3DFMT_A32B32G32R32F │ CL_RGBA, CL_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│D3DFMT_A16B16G16R16F │ CL_RGBA, CL_HALF_FLOAT │
├─────────────────────┼─────────────────────────────────┤
│D3DFMT_A16B16G16R16 │ CL_RGBA, CL_UNORM_INT16 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_A8B8G8R8 │ CL_RGBA, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_X8B8G8R8 │ CL_RGBA, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_A8R8G8B8 │ CL_BGRA, CL_UNORM_INT8 │
├─────────────────────┼─────────────────────────────────┤
│ D3DFMT_X8R8G8B8 │ CL_BGRA, CL_UNORM_INT8 │
└─────────────────────┴─────────────────────────────────┘
Note that D3D9 format names seem to imply that the order of the color channels are
switched relative to OpenCL but this is not the case. For example, layout of channels for
each pixel for D3DFMT_A32FB32FG32FR32F is the same as CL_RGBA, CL_FLOAT.
Properties of media surface objects may be queried using clGetMemObjectInfo(3clc) and
clGetImageInfo(3clc) with param_nameCL_MEM_MEDIA_ADAPTER_TYPE_KHR,
CL_MEM_MEDIA_SURFACE_INFO_KHR and CL_IMAGE_MEDIA_SURFACE_PLANE_KHR as described for
clGetImageInfo(3clc) and in the information below about accessing mapped regions of a
memory object. Accessing mapped regions of a memory object.PP This section describes the
behavior of OpenCL commands that access mapped regions of a memory object.
The contents of the region of a memory object and associated memory objects (sub-buffer
objects or 1D image buffer objects that overlap this region) mapped for writing (i.e.
CL_MAP_WRITE or CL_MAP_WRITE_INVALIDATE_REGION is set in map_flags argument to
clEnqueueMapBuffer(3clc) or clEnqueueMapImage(3clc)) are considered to be undefined until
this region is unmapped.
Multiple commands in command-queues can map a region or overlapping regions of a memory
object and associated memory objects (sub-buffer objects or 1D image buffer objects that
overlap this region) for reading (i.e. map_flags = CL_MAP_READ). The contents of the
regions of a memory object mapped for reading can also be read by kernels and other OpenCL
commands (such as clEnqueueCopyBuffer(3clc)) executing on a device(s).
Mapping (and unmapping) overlapped regions in a memory object and/or associated memory
objects (sub-buffer objects or 1D image buffer objects that overlap this region) for
writing is an error and will result in CL_INVALID_OPERATION error returned by
clEnqueueMapBuffer(3clc) or clEnqueueMapImage(3clc).
If a memory object is currently mapped for writing, the application must ensure that the
memory object is unmapped before any enqueued kernels or commands that read from or write
to this memory object or any of its associated memory objects (sub-buffer or 1D image
buffer objects) or its parent object (if the memory object is a sub-buffer or 1D image
buffer object) begin execution; otherwise the behavior is undefined.
If a memory object is currently mapped for reading, the application must ensure that the
memory object is unmapped before any enqueued kernels or commands that write to this
memory object or any of its associated memory objects (sub-buffer or 1D image buffer
objects) or its parent object (if the memory object is a sub-buffer or 1D image buffer
object) begin execution; otherwise the behavior is undefined.
Accessing the contents of the memory region referred to by the mapped pointer that has
been unmapped is undefined.
The mapped pointer returned by clEnqueueMapBuffer(3clc) or clEnqueueMapImage(3clc) can be
used as ptr argument value to clEnqueueReadBuffer(3clc), clEnqueueWriteBuffer(3clc),
clEnqueueReadBufferRect(3clc), clEnqueueWriteBufferRect(3clc), clEnqueueReadImage(3clc),
and clEnqueueWriteImage(3clc), provided the rules described above are adhered to.
ERRORS
Returns CL_SUCCESS returns a valid non-zero 2D image object and errcode_ret is set to
CL_SUCCESS if the 2D image object is created successfully. Otherwise, it returns a NULL
value with one of the following error values returned in errcode_ret:
· CL_INVALID_CONTEXT if context is not a valid context.
· CL_INVALID_VALUE if values specified in flags are not valid or if plane is not a valid
plane of resource specified in surface_info..
· CL_INVALID_DX9_MEDIA_SURFACE_KHR if resource specified in surface_info is not a valid
resource or is not associated with adapter_type (e.g., adapter_type is set to
CL_ADAPTER_D3D9_KHR and resource is not a Direct3D 9 surface created in
D3DPOOL_DEFAULT).
· CL_INVALID_DX9_MEDIA_SURFACE_KHR if shared_handle specified in surface_info is not
NULL or a valid handle value.
· CL_INVALID_IMAGE_FORMAT_DESCRIPTOR if the texture format of resource is not listed in
tables 9.10.3 and 9.10.4.
· CL_INVALID_OPERATION if there are no devices in context that support adapter_type.
· CL_OUT_OF_RESOURCES if there is a failure to allocate resources required by the OpenCL
implementation on the device.
· CL_OUT_OF_HOST_MEMORY if there is a failure to allocate resources required by the
OpenCL implementation on the host.
SPECIFICATION
OpenCL Specification[1]
SEE ALSO
cl_khr_dx9_media_sharing(3clc), clGetDeviceIDsFromDX9MediaAdapterKHR(3clc),
clEnqueueAcquireDX9MediaSurfacesKHR(3clc), clEnqueueReleaseDX9MediaSurfacesKHR(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 89, section 9.10.7.2 Creating Media Resources as OpenCL Image Objects