/* GStreamer aggregator base class * Copyright (C) 2014 Mathieu Duponchelle * Copyright (C) 2014 Thibault Saunier * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifndef __GST_AGGREGATOR_H__ #define __GST_AGGREGATOR_H__ #include #include G_BEGIN_DECLS /************************** * GstAggregator Structs * *************************/ typedef struct _GstAggregator GstAggregator; typedef struct _GstAggregatorPrivate GstAggregatorPrivate; typedef struct _GstAggregatorClass GstAggregatorClass; /************************ * GstAggregatorPad API * ***********************/ #define GST_TYPE_AGGREGATOR_PAD (gst_aggregator_pad_get_type()) #define GST_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPad)) #define GST_AGGREGATOR_PAD_CAST(obj) ((GstAggregatorPad *)(obj)) #define GST_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass)) #define GST_AGGREGATOR_PAD_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass)) #define GST_IS_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR_PAD)) #define GST_IS_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR_PAD)) /**************************** * GstAggregatorPad Structs * ***************************/ typedef struct _GstAggregatorPad GstAggregatorPad; typedef struct _GstAggregatorPadClass GstAggregatorPadClass; typedef struct _GstAggregatorPadPrivate GstAggregatorPadPrivate; /** * GstAggregatorPad: * @segment: last segment received. * * The implementation the GstPad to use with #GstAggregator */ struct _GstAggregatorPad { GstPad parent; /*< public >*/ /* Protected by the OBJECT_LOCK */ GstSegment segment; /* < private > */ GstAggregatorPadPrivate * priv; gpointer _gst_reserved[GST_PADDING]; }; /** * GstAggregatorPadClass: * @flush: Optional * Called when the pad has received a flush stop, this is the place * to flush any information specific to the pad, it allows for individual * pads to be flushed while others might not be. * @skip_buffer: Optional * Called before input buffers are queued in the pad, return %TRUE * if the buffer should be skipped. * */ struct _GstAggregatorPadClass { GstPadClass parent_class; GstFlowReturn (*flush) (GstAggregatorPad * aggpad, GstAggregator * aggregator); gboolean (*skip_buffer) (GstAggregatorPad * aggpad, GstAggregator * aggregator, GstBuffer * buffer); /*< private >*/ gpointer _gst_reserved[GST_PADDING_LARGE]; }; GST_BASE_API GType gst_aggregator_pad_get_type (void); /**************************** * GstAggregatorPad methods * ***************************/ GST_BASE_API GstBuffer * gst_aggregator_pad_pop_buffer (GstAggregatorPad * pad); GST_BASE_API GstBuffer * gst_aggregator_pad_peek_buffer (GstAggregatorPad * pad); GST_BASE_API gboolean gst_aggregator_pad_drop_buffer (GstAggregatorPad * pad); GST_BASE_API gboolean gst_aggregator_pad_has_buffer (GstAggregatorPad * pad); GST_BASE_API gboolean gst_aggregator_pad_is_eos (GstAggregatorPad * pad); /********************* * GstAggregator API * ********************/ #define GST_TYPE_AGGREGATOR (gst_aggregator_get_type()) #define GST_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR,GstAggregator)) #define GST_AGGREGATOR_CAST(obj) ((GstAggregator *)(obj)) #define GST_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR,GstAggregatorClass)) #define GST_AGGREGATOR_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR,GstAggregatorClass)) #define GST_IS_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR)) #define GST_IS_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR)) #define GST_AGGREGATOR_FLOW_NEED_DATA GST_FLOW_CUSTOM_ERROR /** * GstAggregator: * @srcpad: the aggregator's source pad * * Aggregator base class object structure. */ struct _GstAggregator { GstElement parent; /*< public >*/ GstPad * srcpad; /*< private >*/ GstAggregatorPrivate * priv; gpointer _gst_reserved[GST_PADDING_LARGE]; }; /** * GstAggregatorClass: * @flush: Optional. * Called after a successful flushing seek, once all the flush * stops have been received. Flush pad-specific data in * #GstAggregatorPad->flush. * @clip: Optional. * Called when a buffer is received on a sink pad, the task of * clipping it and translating it to the current segment falls * on the subclass. The function should use the segment of data * and the negotiated media type on the pad to perform * clipping of input buffer. This function takes ownership of * buf and should output a buffer or return NULL in * if the buffer should be dropped. * @finish_buffer: Optional. * Called when a subclass calls gst_aggregator_finish_buffer() * from their aggregate function to push out a buffer. * Subclasses can override this to modify or decorate buffers * before they get pushed out. This function takes ownership * of the buffer passed. Subclasses that override this method * should always chain up to the parent class virtual method. * @sink_event: Optional. * Called when an event is received on a sink pad, the subclass * should always chain up. * @sink_query: Optional. * Called when a query is received on a sink pad, the subclass * should always chain up. * @src_event: Optional. * Called when an event is received on the src pad, the subclass * should always chain up. * @src_query: Optional. * Called when a query is received on the src pad, the subclass * should always chain up. * @src_activate: Optional. * Called when the src pad is activated, it will start/stop its * pad task right after that call. * @aggregate: Mandatory. * Called when buffers are queued on all sinkpads. Classes * should iterate the GstElement->sinkpads and peek or steal * buffers from the #GstAggregatorPads. If the subclass returns * GST_FLOW_EOS, sending of the eos event will be taken care * of. Once / if a buffer has been constructed from the * aggregated buffers, the subclass should call _finish_buffer. * @stop: Optional. * Called when the element goes from PAUSED to READY. * The subclass should free all resources and reset its state. * @start: Optional. * Called when the element goes from READY to PAUSED. * The subclass should get ready to process * aggregated buffers. * @get_next_time: Optional. * Called when the element needs to know the running time of the next * rendered buffer for live pipelines. This causes deadline * based aggregation to occur. Defaults to returning * GST_CLOCK_TIME_NONE causing the element to wait for buffers * on all sink pads before aggregating. * @create_new_pad: Optional. * Called when a new pad needs to be created. Allows subclass that * don't have a single sink pad template to provide a pad based * on the provided information. * @update_src_caps: Lets subclasses update the #GstCaps representing * the src pad caps before usage. The result should end up * in @ret. Return %GST_AGGREGATOR_FLOW_NEED_DATA to indicate that the * element needs more information (caps, a buffer, etc) to * choose the correct caps. Should return ANY caps if the * stream has not caps at all. * @fixate_src_caps: Optional. * Fixate and return the src pad caps provided. The function takes * ownership of @caps and returns a fixated version of * @caps. @caps is not guaranteed to be writable. * @negotiated_src_caps: Optional. * Notifies subclasses what caps format has been negotiated * @decide_allocation: Optional. * Allows the subclass to influence the allocation choices. * Setup the allocation parameters for allocating output * buffers. The passed in query contains the result of the * downstream allocation query. * @propose_allocation: Optional. * Allows the subclass to handle the allocation query from upstream. * * 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. */ struct _GstAggregatorClass { GstElementClass parent_class; GstFlowReturn (*flush) (GstAggregator * aggregator); GstBuffer * (*clip) (GstAggregator * aggregator, GstAggregatorPad * aggregator_pad, GstBuffer * buf); GstFlowReturn (*finish_buffer) (GstAggregator * aggregator, GstBuffer * buffer); /* sinkpads virtual methods */ gboolean (*sink_event) (GstAggregator * aggregator, GstAggregatorPad * aggregator_pad, GstEvent * event); gboolean (*sink_query) (GstAggregator * aggregator, GstAggregatorPad * aggregator_pad, GstQuery * query); /* srcpad virtual methods */ gboolean (*src_event) (GstAggregator * aggregator, GstEvent * event); gboolean (*src_query) (GstAggregator * aggregator, GstQuery * query); gboolean (*src_activate) (GstAggregator * aggregator, GstPadMode mode, gboolean active); GstFlowReturn (*aggregate) (GstAggregator * aggregator, gboolean timeout); gboolean (*stop) (GstAggregator * aggregator); gboolean (*start) (GstAggregator * aggregator); GstClockTime (*get_next_time) (GstAggregator * aggregator); GstAggregatorPad * (*create_new_pad) (GstAggregator * self, GstPadTemplate * templ, const gchar * req_name, const GstCaps * caps); /** * GstAggregatorClass::update_src_caps: * @ret: (out) (allow-none): */ GstFlowReturn (*update_src_caps) (GstAggregator * self, GstCaps * caps, GstCaps ** ret); GstCaps * (*fixate_src_caps) (GstAggregator * self, GstCaps * caps); gboolean (*negotiated_src_caps) (GstAggregator * self, GstCaps * caps); gboolean (*decide_allocation) (GstAggregator * self, GstQuery * query); gboolean (*propose_allocation) (GstAggregator * self, GstAggregatorPad * pad, GstQuery * decide_query, GstQuery * query); /*< private >*/ gpointer _gst_reserved[GST_PADDING_LARGE]; }; /************************************ * GstAggregator convenience macros * ***********************************/ /** * GST_AGGREGATOR_SRC_PAD: * @agg: a #GstAggregator * * Convenience macro to access the source pad of #GstAggregator * * Since: 1.6 */ #define GST_AGGREGATOR_SRC_PAD(agg) (((GstAggregator *)(agg))->srcpad) /************************* * GstAggregator methods * ************************/ GST_BASE_API GstFlowReturn gst_aggregator_finish_buffer (GstAggregator * aggregator, GstBuffer * buffer); GST_BASE_API void gst_aggregator_set_src_caps (GstAggregator * self, GstCaps * caps); GST_BASE_API void gst_aggregator_set_latency (GstAggregator * self, GstClockTime min_latency, GstClockTime max_latency); GST_BASE_API GType gst_aggregator_get_type(void); GST_BASE_API GstClockTime gst_aggregator_get_latency (GstAggregator * self); GST_BASE_API GstBufferPool * gst_aggregator_get_buffer_pool (GstAggregator * self); GST_BASE_API void gst_aggregator_get_allocator (GstAggregator * self, GstAllocator ** allocator, GstAllocationParams * params); GST_BASE_API GstClockTime gst_aggregator_simple_get_next_time (GstAggregator * self); G_END_DECLS #ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregator, gst_object_unref) G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregatorPad, gst_object_unref) #endif #endif /* __GST_AGGREGATOR_H__ */