Class: GstBase::Aggregator

Inherits:
Gst::Element show all
Defined in:
(unknown)

Overview

The aggregator base class will handle in a thread-safe way all manners of
concurrent flushes, seeks, pad additions and removals, leaving to the
subclass the responsibility of clipping buffers, and aggregating buffers in
the way the implementor sees fit.

It will also take care of event ordering (stream-start, segment, eos).

Basically, a simple implementation will override aggregate, and call
_finish_buffer from inside that function.

Direct Known Subclasses

GstAudio::AudioAggregator

Instance Method Summary collapse

Methods inherited from Gst::Element

#>>, [], #abort_state, #add_metadata, #add_pad, #add_pad_template, #add_property_deep_notify_watch, #add_property_notify_watch, #add_static_metadata, #add_static_pad_template, #add_static_pad_template_with_gtype, #base_time, #base_time=, #bus, #bus=, #call_async, #change_state, #clock, #clock=, #context=, #contexts, #continue_state, #create_all_pads, #current_clock_time, #current_running_time, #decorate_stream_id, #decorate_stream_id_printf, #decorate_stream_id_printf_valist, #factory, #flags, #flags_raw, #foreach_pad, #foreach_sink_pad, #foreach_src_pad, #get_compatible_pad, #get_compatible_pad_template, #get_context, #get_context_unlocked, #get_metadata, #get_pad_template, #get_request_pad, #get_state, #get_static_pad, #is_locked_state, #iterate_pads, #iterate_sink_pads, #iterate_src_pads, #link_elements, #link_filtered, #link_many, #link_pads, #link_pads_filtered, #link_pads_full, #locked_state=, #lost_state, make_from_uri, #message_full, #message_full_with_details, #no_more_pads, #pad_template_list, #pause, #play, #post_message, #provide_clock, #query, #query_convert, #query_duration, #query_position, #ready, register, #release_request_pad, #remove_pad, #remove_property_notify_watch, #request_pad, #request_pad_simple, #seek, #seek_simple, #send_event, #set_metadata, #set_static_metadata, #state=, state_change_return_get_name, state_get_name, #stop, #sync_state_with_parent, type_set_skip_documentation, #unlink, #unlink_many, #unlink_pads

Methods inherited from Gst::Object

#add_control_binding, check_uniqueness, #control_bindings_disabled=, #control_rate, #control_rate=, default_deep_notify, #default_error, #get_control_binding, #get_g_value_array, #get_value, #get_value_array, #has_active_control_bindings, #has_ancestor, #has_as_ancestor, #has_as_parent, #name, #name=, #parent, #parent=, #path_string, #ref, ref_sink, #remove_control_binding, replace, #set_control_binding_disabled, #suggest_next_sync, #sync_values, #unparent, #unref

Instance Method Details

#buffer_pool ⇒ Gst::BufferPool

by trans; free it after use it

Returns:

#emit_signals=(emit_signals) ⇒ Boolean

Enables the emission of signals such as Gst::Aggregator::samples-selected

Parameters:

  • emit_signals (Boolean)

Returns:

  • (Boolean) —

    emit-signals

  • (Boolean) —

    emit-signals

#emit_signals? ⇒ Boolean

Enables the emission of signals such as Gst::Aggregator::samples-selected

Returns:

  • (Boolean) —

    emit-signals

#finish_buffer(buffer) ⇒ Gst::FlowReturn

This method will push the provided output buffer downstream. If needed,
mandatory events such as stream-start, caps, and segment events will be
sent before pushing the buffer.

Parameters:

Returns:

#finish_buffer_list(bufferlist) ⇒ Gst::FlowReturn

This method will push the provided output buffer list downstream. If needed,
mandatory events such as stream-start, caps, and segment events will be
sent before pushing the buffer.

Parameters:

  • bufferlist (Gst::BufferList) —

    the Gst::BufferList to push.

Returns:

#force_live ⇒ Boolean

Subclasses may use the return value to inform whether they should return
%GST_FLOW_EOS from their aggregate implementation.

Returns:

  • (Boolean) —

    whether live status was forced on self.

#force_live=(force_live) ⇒ nil

Subclasses should call this at construction time in order for self to
aggregate on a timeout even when no live source is connected.

Parameters:

  • force_live (Boolean)

Returns:

  • (nil)

#get_allocator(allocator, params) ⇒ nil

Lets Gst::Aggregator sub-classes get the memory allocator
acquired by the base class and its params.

Unref the allocator after use it.
used
Gst::AllocationParams of allocator

Parameters:

  • allocator (Gst::Allocator) —

    the Gst::Allocator

  • params (Gst::AllocationParams) —

    the

Returns:

  • (nil)

#ignore_inactive_pads ⇒ Boolean

Returns whether inactive pads will not be waited on.

Returns:

  • (Boolean) —

    whether inactive pads will not be waited on

#ignore_inactive_pads=(ignore) ⇒ nil

Subclasses should call this when they don't want to time out
waiting for a pad that hasn't yet received any buffers in live
mode.

Gst::Aggregator will still wait once on each newly-added pad, making
sure upstream has had a fair chance to start up.

Parameters:

  • ignore (Boolean) —

    whether inactive pads should not be waited on

Returns:

  • (nil)

#latency ⇒ Integer

Returns latency.

Returns:

  • (Integer) —

    latency

#latency=(latency) ⇒ Integer

Parameters:

  • latency (Integer)

Returns:

  • (Integer) —

    latency

  • (Integer) —

    latency

#min_upstream_latency ⇒ Integer

Force minimum upstream latency (in nanoseconds). When sources with a
higher latency are expected to be plugged in dynamically after the
aggregator has started playing, this allows overriding the minimum
latency reported by the initial source(s). This is only taken into
account when larger than the actually reported minimum latency.

Returns:

  • (Integer) —

    min-upstream-latency

#min_upstream_latency=(min_upstream_latency) ⇒ Integer

Force minimum upstream latency (in nanoseconds). When sources with a
higher latency are expected to be plugged in dynamically after the
aggregator has started playing, this allows overriding the minimum
latency reported by the initial source(s). This is only taken into
account when larger than the actually reported minimum latency.

Parameters:

  • min_upstream_latency (Integer)

Returns:

  • (Integer) —

    min-upstream-latency

  • (Integer) —

    min-upstream-latency

#negotiate ⇒ Boolean

Negotiates src pad caps with downstream elements.
Unmarks GST_PAD_FLAG_NEED_RECONFIGURE in any case. But marks it again
if Gst::AggregatorClass::negotiate fails.

Returns:

  • (Boolean) —

    true if the negotiation succeeded, else false.

#peek_next_sample(pad) ⇒ Gst::Sample

Use this function to determine what input buffers will be aggregated
to produce the next output buffer. This should only be called from
a Gst::Aggregator::samples-selected handler, and can be used to precisely
control aggregating parameters for a given set of input samples.

Parameters:

Returns:

  • (Gst::Sample) —

    The sample that is about to be aggregated. It may hold a Gst::Buffer
    or a Gst::BufferList. The contents of its info structure is subclass-dependent,
    and documented on a subclass basis. The buffers held by the sample are
    not writable.

#selected_samples(pts, dts, duration, info) ⇒ nil

Subclasses should call this when they have prepared the
buffers they will aggregate for each of their sink pads, but
before using any of the properties of the pads that govern
how aggregation should be performed, for example z-index
for video aggregators.

If gst_aggregator_update_segment() is used by the subclass,
it MUST be called before gst_aggregator_selected_samples().

This function MUST only be called from the Gst::AggregatorClass::aggregate()
function.

Parameters:

  • pts (Gst::ClockTime) —

    The presentation timestamp of the next output buffer

  • dts (Gst::ClockTime) —

    The decoding timestamp of the next output buffer

  • duration (Gst::ClockTime) —

    The duration of the next output buffer

  • info (Gst::Structure) —

    a Gst::Structure containing additional information

Returns:

  • (nil)

#set_latency(min_latency, max_latency) ⇒ nil

Lets Gst::Aggregator sub-classes tell the baseclass what their internal
latency is. Will also post a LATENCY message on the bus so the pipeline
can reconfigure its global latency if the values changed.

Parameters:

  • min_latency (Gst::ClockTime) —

    minimum latency

  • max_latency (Gst::ClockTime) —

    maximum latency

Returns:

  • (nil)

#simple_get_next_time ⇒ Gst::ClockTime

This is a simple Gst::AggregatorClass::get_next_time implementation that
just looks at the Gst::Segment on the srcpad of the aggregator and bases
the next time on the running time there.

This is the desired behaviour in most cases where you have a live source
and you have a dead line based aggregator subclass.

Returns:

  • (Gst::ClockTime) —

    The running time based on the position

#src_caps=(caps) ⇒ nil

Sets the caps to be used on the src pad.

Parameters:

  • caps (Gst::Caps) —

    The Gst::Caps to set on the src pad.

Returns:

  • (nil)

#start_time ⇒ Integer

Returns start-time.

Returns:

  • (Integer) —

    start-time

#start_time=(start_time) ⇒ Integer

Parameters:

  • start_time (Integer)

Returns:

  • (Integer) —

    start-time

  • (Integer) —

    start-time

#start_time_selection ⇒ GstBase::AggregatorStartTimeSelection

Returns start-time-selection.

Returns:

#start_time_selection=(start_time_selection) ⇒ GstBase::AggregatorStartTimeSelection

Parameters:

Returns:

#update_segment(segment) ⇒ nil

Subclasses should use this to update the segment on their
source pad, instead of directly pushing new segment events
downstream.

Subclasses MUST call this before gst_aggregator_selected_samples(),
if it is used at all.

Parameters:

  • segment (Gst::Segment)

Returns:

  • (nil)