GstVulkan.VulkanOperation¶

Subclasses:: None

Methods¶

Inherited:: Gst.Object (27), GObject.Object (37)
Structs:: GObject.ObjectClass (5)

class	`new` (cmd_pool)
	`add_dependency_frame` (frame, wait_stage, signal_stage)
	`add_frame_barrier` (frame, src_stage, dst_stage, new_access, new_layout, new_queue)
	`begin` ()
	`begin_query` (base, id)
	`discard_dependencies` ()
	`enable_query` (query_type, n_queries, pnext)
	`end` ()
	`end_query` (id)
	`get_query` ()
	`pipeline_barrier2` (dependency_info)
	`reset` ()
	`update_frame` (frame, dst_stage, new_access, new_layout, new_queue)
	`use_sync2` ()
	`wait` ()

Virtual Methods¶

Inherited:: Gst.Object (1), GObject.Object (7)

Properties¶

Inherited:: Gst.Object (2)

Name	Type	Flags	Short Description
`command-pool`	`GstVulkan.VulkanCommandPool`	r/w/co	Vulkan Command Pool

Signals¶

Inherited:: Gst.Object (1), GObject.Object (1)

Fields¶

Inherited:: Gst.Object (1), GObject.Object (1)

Name	Type	Access	Description
cmd_buf	`GstVulkan.VulkanCommandBuffer`	r	the current `GstVulkan.VulkanCommandBuffer`
parent	`Gst.Object`	r	the parent `Gst.Object`

Class Details¶

class GstVulkan.VulkanOperation(**kwargs)¶

Bases:: Gst.Object
Abstract:: No
Structure:: GstVulkan.VulkanOperationClass

When using the operation cmd_buf, you should lock it using gst_vulkan_command_buffer_lock(), but you have to unlock it, with gst_vulkan_command_buffer_unlock(), when calling any of GstVulkan.VulkanOperation methods.

New in version 1.24.

classmethod new(cmd_pool)¶

Parameters:: cmd_pool (GstVulkan.VulkanCommandPool) – a GstVulkan.VulkanCommandPool
Returns:: a newly allocated GstVulkan.VulkanOperation
Return type:: GstVulkan.VulkanOperation

add_dependency_frame(frame, wait_stage, signal_stage)¶

Parameters:

frame (Gst.Buffer) – a Vulkan Image Gst.Buffer
wait_stage (int) – pipeline stage to wait (Vulkan.PipelineStageFlags or Vulkan.PipelineStageFlags2)
signal_stage (int) – pipeline stage to signal (Vulkan.PipelineStageFlags or Vulkan.PipelineStageFlags2)

Returns:

whether the frame was added as dependency.

Return type:

bool

Add frame as an operation dependency by adding the timeline semaphores in each memory of frame into either the wait semaphore array. The signal array hold the same semaphores but increasing their current value.

add_frame_barrier(frame, src_stage, dst_stage, new_access, new_layout, new_queue)¶

Parameters:

frame (Gst.Buffer) – a Vulkan Image Gst.Buffer
src_stage (int) – source pipeline stage (Vulkan.PipelineStageFlags or Vulkan.PipelineStageFlags2)
dst_stage (int) – destination pipeline stage (Vulkan.PipelineStageFlags or Vulkan.PipelineStageFlags2)
new_access (int) – the new access flags (Vulkan.AccessFlags2 or Vulkan.AccessFlags)
new_layout (Vulkan.ImageLayout) – the new Vulkan.ImageLayout
new_queue (GstVulkan.VulkanQueue or None) – destination GstVulkan.VulkanQueue for a transfer of frame ownership

Returns:

whether the frame barriers were appended

Return type:

bool

Adds an image memory barrier per memory in frame with its future state. And it updates the frame barrier state by calling internally GstVulkan.VulkanOperation.update_frame().

begin()¶

Raises:: GLib.Error
Returns:: whether the operation started. It might fill error.
Return type:: bool

Attempts to set the operation ready to work. It instantiates the common command buffer in self and calls vkBeginCommandBuffer.

After calling this function you can register commands in the command buffer, and finally call GstVulkan.VulkanOperation.end(). GstVulkan.VulkanOperation.reset() is called internally if something failed.

begin_query(base, id)¶

Parameters:

base (Vulkan.BaseInStructure) – a Vulkan.BaseInStructure base
id (int) – query id

Returns:

whether the begin command was set

Return type:

bool

Begins a query operation with id in the current command buffer. If video maintenance1 extension is available the query will be recorded as a video inline query. If None is passed to base, the query will be recorded as a normal query anyway.

New in version 1.26.

discard_dependencies()¶: Discards barriers, and all the semaphore arrays populated by GstVulkan.VulkanOperation.add_dependency_frame().

enable_query(query_type, n_queries, pnext)¶

Parameters:

query_type (int) – the Vulkan.QueryType to enable
n_queries (int) – number of queries to enable
pnext (object or None) – the structure pointer to use as pNext

Raises:

GLib.Error

Returns:

whether the query pool was enabled. It might populate error in case of error.

Return type:

bool

Tries to enable the query pool for the current operation.

New in version 1.24.

end()¶

Raises:: GLib.Error
Returns:: whether the operation failed. It might fill error.
Return type:: bool

It calls vkEndCommandBuffer, and later either vkQueueSubmit or vkQueueSubmit2KHR filling up the semaphores from images declared as dependencies.

You have called GstVulkan.VulkanOperation.begin() before. GstVulkan.VulkanOperation.reset() is called internally if something fails

end_query(id)¶

Parameters:: id (int) – query id
Returns:: whether the end command was set
Return type:: bool

Ends a query operation with id in the current command buffer. A query with id has had started with GstVulkan.VulkanOperation.begin_query()

get_query()¶

Raises:

GLib.Error

Returns:

whether a status was fetched. If not, it might populate error

data:: result of all queries

Return type:

(bool, data: object)

Gets the latest operation results of all the queries in data. API users have to parse the binary array of data according of their needs (usually is a guint32 array of size of n_query).

Don’t free data.

pipeline_barrier2(dependency_info)¶

Parameters:: dependency_info (object or None) – a pointer to Vulkan.DependencyInfo
Returns:: True if vkCmdPipelineBarrier2{KHR} it’s available. False, otherwise.
Return type:: bool

It’s a wrapper to vkCmdPipelineBarrier2{KHR} if it’s available.

reset()¶: Resets the operation to a clean state.

update_frame(frame, dst_stage, new_access, new_layout, new_queue)¶

Parameters:

frame (Gst.Buffer) – a Gst.Buffer to update after submit
dst_stage (int) – destination pipeline stage (Vulkan.PipelineStageFlags or Vulkan.PipelineStageFlags2)
new_access (int) – the new access flags (Vulkan.AccessFlags2 or Vulkan.AccessFlags)
new_layout (Vulkan.ImageLayout) – the new Vulkan.ImageLayout
new_queue (GstVulkan.VulkanQueue or None) – destination GstVulkan.VulkanQueue for a transfer of frame ownership

Add or update the internal list of the future state of frame. This state will be set after GstVulkan.VulkanOperation.end().

This method is useful when new barriers are added to the array without using GstVulkan.VulkanOperation.add_frame_barrier().

use_sync2()¶

Returns:: whether the operations are using synchronization2 extension.
Return type:: bool

wait()¶

Returns:: whether the operation succeed.
Return type:: bool

Waits for the operation’s fence to signal.

Property Details¶

GstVulkan.VulkanOperation.props.command_pool¶

Name:: command-pool
Type:: GstVulkan.VulkanCommandPool
Default Value:: None
Flags:: READABLE, WRITABLE, CONSTRUCT_ONLY

Vulkan Command Pool