Functions¶

	`buffer_pool_config_set_va_alignment` (config, align)
	`buffer_pool_config_set_va_allocation_params` (config, usage_hint, use_derived)
	`context_get_va_display` (context, type_name, render_device_path)
	`context_set_va_display` (context, display)
	`va_buffer_create_aux_surface` (buffer)
	`va_buffer_peek_display` (buffer)
	`va_context_query` (element, context_type)
	`va_dmabuf_get_modifier_for_format` (display, format, usage_hint)
	`va_dmabuf_memories_setup` (display, drm_info, mem, fds, offset, usage_hint)
	`va_element_propagate_display_context` (element, display)
	`va_ensure_element_data` (element, render_device_path)
	`va_handle_context_query` (element, query, display)
	`va_handle_set_context` (element, context, render_device_path)
	`va_memory_peek_display` (mem)

Details¶

GstVa.buffer_pool_config_set_va_alignment(config, align)¶

Parameters:

config (Gst.Structure) – the Gst.Structure with the pool’s configuration.
align (GstVideo.VideoAlignment) – a GstVideo.VideoAlignment

Video alignment is not handled as expected by VA since it uses opaque surfaces, not directly mappable memory. Still, decoders might need to request bigger surfaces for coded size rather than display sizes. This method will set the coded size to bufferpool’s configuration, out of the typical video aligment.

Added in version 1.20.2.

GstVa.buffer_pool_config_set_va_allocation_params(config, usage_hint, use_derived)¶

Parameters:

config (Gst.Structure) – the Gst.Structure with the pool’s configuration.
usage_hint (int) – the VA usage hint for new VASurfaceID.
use_derived (GstVa.VaFeature) – a GstVa.VaFeature for derived mapping (only used when VA allocator).

Sets the usage hint for the buffers handled by the buffer pool.

Added in version 1.22.

GstVa.context_get_va_display(context, type_name, render_device_path)¶

Parameters:

context (Gst.Context) – a Gst.Context may contain the display
type_name (str) – a str string of the element type
render_device_path (str) – the str string of render device path

Returns:

whether we find a valid display in the context

display_ptr:: the GstVa.VaDisplay we get

Return type:

(bool, display_ptr: GstVa.VaDisplay)

Added in version 1.22.

GstVa.context_set_va_display(context, display)¶

Parameters:

context (Gst.Context) – a Gst.Context
display (GstVa.VaDisplay) – the GstVa.VaDisplay we want to set

Set the display in the context

Added in version 1.22.

GstVa.va_buffer_create_aux_surface(buffer)¶

Parameters:: buffer (Gst.Buffer) – a Gst.Buffer
Returns:: True if the new VASurfaceID is attached to buffer correctly; False, otherwise.
Return type:: bool

Creates a new VASurfaceID with buffer's allocator and attached it to it.

*This method is used only by plugin’s internal VA decoder.*

Added in version 1.22.

GstVa.va_buffer_peek_display(buffer)¶

Parameters:: buffer (Gst.Buffer) – a Gst.Buffer
Returns:: the display which this buffer belongs to. The reference of the display is unchanged.
Return type:: GstVa.VaDisplay

Added in version 1.22.

GstVa.va_context_query(element, context_type)¶

Parameters:

element (Gst.Element) – a Gst.Element
context_type (str) – the str string specify the context type name

Query the specified context type name.

Added in version 1.22.

GstVa.va_dmabuf_get_modifier_for_format(display, format, usage_hint)¶

Parameters:

display (GstVa.VaDisplay) – a GstVa.VaDisplay
format (GstVideo.VideoFormat) – a GstVideo.VideoFormat
usage_hint (int) – VA usage hint

Returns:

the underlying modifier.

Return type:

int

Get the underlying modifier for specified format and usage_hint.

Added in version 1.24.

GstVa.va_dmabuf_memories_setup(display, drm_info, mem, fds, offset, usage_hint)¶

Parameters:

display (GstVa.VaDisplay) – a GstVa.VaDisplay
drm_info (GstVideo.VideoInfoDmaDrm) – a GstVideo.VideoInfoDmaDrm
mem ([Gst.Memory]) – Memories. One per plane.
fds ([int]) – array of DMABuf file descriptors.
offset ([int]) – array of memory offsets.
usage_hint (int) – VA usage hint.

Returns:

True if frame is imported correctly into a VASurfaceID; False otherwise.

Return type:

bool

It imports the array of mem, representing a single frame, into a VASurfaceID and it’s attached into every mem.

Added in version 1.22.

GstVa.va_element_propagate_display_context(element, display)¶

Parameters:

element (Gst.Element) – a Gst.Element
display (GstVa.VaDisplay) – the GstVa.VaDisplay to propagate

Propagate display by posting it as Gst.Context in the pipeline’s bus.

Added in version 1.22.

GstVa.va_ensure_element_data(element, render_device_path)¶

Parameters:

element (object or None) – a Gst.Element
render_device_path (str) – the str string of render device path

Returns:

whether a GstVa.VaDisplay exists in display_ptr

display_ptr:: The GstVa.VaDisplay to ensure

Return type:

(bool, display_ptr: GstVa.VaDisplay)

Called by the va element to ensure a valid GstVa.VaDisplay.

Added in version 1.22.

GstVa.va_handle_context_query(element, query, display)¶

Parameters:

element (Gst.Element) – a Gst.Element
query (Gst.Query) – a Gst.Query to query the context
display (GstVa.VaDisplay) – a GstVa.VaDisplay to answer the query

Returns:

whether we can handle the context query successfully

Return type:

bool

Used by elements when processing their pad’s queries, propagating element’s GstVa.VaDisplay if the processed query requests it.

Added in version 1.22.

GstVa.va_handle_set_context(element, context, render_device_path)¶

Parameters:

element (Gst.Element) – a Gst.Element
context (Gst.Context) – a Gst.Context may contain the display
render_device_path (str) – the str string of render device path

Returns:

whether the display_ptr could be successfully set to a valid GstVa.VaDisplay in the context

display_ptr:: The GstVa.VaDisplay to set

Return type:

(bool, display_ptr: GstVa.VaDisplay)

Called by elements in their #GstElementClass::set_context vmethod. It gets a valid GstVa.VaDisplay if context has it.

Added in version 1.22.

GstVa.va_memory_peek_display(mem)¶

Parameters:: mem (Gst.Memory) – a Gst.Memory
Returns:: the display which this mem belongs to. The reference of the display is unchanged.
Return type:: GstVa.VaDisplay

Added in version 1.22.