Enqueues a command to copy an image object to a buffer object.

cl_int clEnqueueCopyImageToBuffer ( cl_command_queue command_queue,
  cl_mem src_image,
  cl_mem  dst_buffer,
  const size_t src_origin[3],
  const size_t region[3],
  size_t dst_offset,
  cl_uint num_events_in_wait_list,
  const cl_event *event_wait_list,
  cl_event *event)



Must be a valid command-queue. The OpenCL context associated with command_queue, src_image, and dst_buffer must be the same.


A valid image object.


A valid buffer object.


Defines the (x, y, z) offset in pixels in the image from where to copy. If src_image is a 2D image object, the z value given by src_origin[2] must be 0.


Defines the (width, height, depth) in pixels of the 2D or 3D rectangle to copy. If src_image is a 2D image object, the depth value given by region[2] must be 1.


The offset where to begin copying data into dst_buffer. The size in bytes of the region to be copied referred to as dst_cb is computed as width * height * depth * bytes/image element if src_image is a 3D image object and is computed as width * height * bytes/image element if src_image is a 2D image object.

event_wait_list , num_events_in_wait_list

Specify events that need to complete before this particular command can be executed. If event_wait_list is NULL, then this particular command does not wait on any event to complete. If event_wait_list is NULL, num_events_in_wait_list must be 0. If event_wait_list is not NULL, the list of events pointed to by event_wait_list must be valid and num_events_in_wait_list must be greater than 0. The events specified in event_wait_list act as synchronization points. The context associated with events in event_wait_list and command_queue must be the same.


Returns an event object that identifies this particular copy command and can be used to query or queue a wait for this particular command to complete. event can be NULL in which case it will not be possible for the application to query the status of this command or queue a wait for this command to complete. clEnqueueBarrier can be used instead.


clEnqueueCopyImageToBuffer returns CL_SUCCESS if the function is executed successfully. Otherwise, it returns one of the following errors:

  • CL_INVALID_COMMAND_QUEUE if command_queue is not a valid command-queue.
  • CL_INVALID_CONTEXT if the context associated with command_queue, src_image and dst_buffer are not the same or if the context associated with command_queue and events in event_wait_list are not the same.
  • CL_INVALID_MEM_OBJECT if src_image is not a valid image object and dst_buffer is not a valid buffer object.
  • CL_INVALID_VALUE if the 2D or 3D rectangular region specified by src_origin and src_origin + region refers to a region outside src_image, or if the region specified by dst_offset and dst_offset + dst_cb refers to a region outside dst_buffer.
  • CL_INVALID_VALUE if src_image is a 2D image object and src_origin[2] is not equal to 0 or region[2] is not equal to 1.
  • CL_INVALID_EVENT_WAIT_LIST if event_wait_list is NULL and num_events_in_wait_list greater than 0, or event_wait_list is not NULL and num_events_in_wait_list is 0, or if event objects in event_wait_list are not valid events.
  • CL_MISALIGNED_SUB_BUFFER_OFFSET if dst_buffer is a sub-buffer object and offset specified when the sub-buffer object is created is not aligned to CL_DEVICE_MEM_BASE_ADDR_ALIGN value for device associated with queue.
  • CL_INVALID_IMAGE_SIZE if image dimensions (image width, height, specified or compute row and/or slice pitch) for src_image are not supported by device associated with queue.
  • CL_INVALID_OPERATION if the device associated with command_queue does not support images (i.e. CL_DEVICE_IMAGE_SUPPORT specified in the table of OpenCL Device Queries for clGetDeviceInfo is CL_FALSE).
  • CL_MEM_OBJECT_ALLOCATION_FAILURE if there is a failure to allocate memory for data store associated with src_image or dst_buffer.
  • 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.


OpenCL Specification

Also see

clEnqueueReadBuffer, clEnqueueWriteBuffer, clCreateBuffer, clEnqueueCopyBuffer, clEnqueueCopyBufferToImage

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