gstreamer/libs/gst/base/gstbasetransform.h
Wim Taymans 2ff17fb622 basetransform: fix sink event handling
Implement the sink event handling like the src event handler. Make the default
implementation parse and forward the event. This makes it possible to actually
return an error value from the event handler.
2011-07-22 21:17:42 +02:00

287 lines
11 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2005 Wim Taymans <wim@fluendo.com>
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_BASE_TRANSFORM_H__
#define __GST_BASE_TRANSFORM_H__
#include <gst/gst.h>
G_BEGIN_DECLS
#define GST_TYPE_BASE_TRANSFORM (gst_base_transform_get_type())
#define GST_BASE_TRANSFORM(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_BASE_TRANSFORM,GstBaseTransform))
#define GST_BASE_TRANSFORM_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_BASE_TRANSFORM,GstBaseTransformClass))
#define GST_BASE_TRANSFORM_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS((obj),GST_TYPE_BASE_TRANSFORM,GstBaseTransformClass))
#define GST_IS_BASE_TRANSFORM(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_BASE_TRANSFORM))
#define GST_IS_BASE_TRANSFORM_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_BASE_TRANSFORM))
/* since 0.10.4 */
#define GST_BASE_TRANSFORM_CAST(obj) ((GstBaseTransform *)(obj))
/**
* GST_BASE_TRANSFORM_SINK_NAME:
*
* The name of the templates for the sink pad.
*/
#define GST_BASE_TRANSFORM_SINK_NAME "sink"
/**
* GST_BASE_TRANSFORM_SRC_NAME:
*
* The name of the templates for the source pad.
*/
#define GST_BASE_TRANSFORM_SRC_NAME "src"
/**
* GST_BASE_TRANSFORM_SRC_PAD:
* @obj: base transform instance
*
* Gives the pointer to the source #GstPad object of the element.
*
* Since: 0.10.4
*/
#define GST_BASE_TRANSFORM_SRC_PAD(obj) (GST_BASE_TRANSFORM_CAST (obj)->srcpad)
/**
* GST_BASE_TRANSFORM_SINK_PAD:
* @obj: base transform instance
*
* Gives the pointer to the sink #GstPad object of the element.
*
* Since: 0.10.4
*/
#define GST_BASE_TRANSFORM_SINK_PAD(obj) (GST_BASE_TRANSFORM_CAST (obj)->sinkpad)
/**
* GST_BASE_TRANSFORM_FLOW_DROPPED:
*
* A #GstFlowReturn that can be returned from transform and transform_ip to
* indicate that no output buffer was generated.
*
* Since: 0.10.13
*/
#define GST_BASE_TRANSFORM_FLOW_DROPPED GST_FLOW_CUSTOM_SUCCESS
/**
* GST_BASE_TRANSFORM_LOCK:
* @obj: base transform instance
*
* Obtain a lock to protect the transform function from concurrent access.
*
* Since: 0.10.13
*/
#define GST_BASE_TRANSFORM_LOCK(obj) g_mutex_lock (GST_BASE_TRANSFORM_CAST (obj)->transform_lock)
/**
* GST_BASE_TRANSFORM_UNLOCK:
* @obj: base transform instance
*
* Release the lock that protects the transform function from concurrent access.
*
* Since: 0.10.13
*/
#define GST_BASE_TRANSFORM_UNLOCK(obj) g_mutex_unlock (GST_BASE_TRANSFORM_CAST (obj)->transform_lock)
typedef struct _GstBaseTransform GstBaseTransform;
typedef struct _GstBaseTransformClass GstBaseTransformClass;
typedef struct _GstBaseTransformPrivate GstBaseTransformPrivate;
/**
* GstBaseTransform:
*
* The opaque #GstBaseTransform data structure.
*/
struct _GstBaseTransform {
GstElement element;
/*< protected >*/
/* source and sink pads */
GstPad *sinkpad;
GstPad *srcpad;
/* Set by sub-class */
gboolean passthrough;
gboolean always_in_place;
GstCaps *cache_caps1;
gsize cache_caps1_size;
GstCaps *cache_caps2;
gsize cache_caps2_size;
gboolean have_same_caps;
gboolean delay_configure;
gboolean pending_configure;
gboolean negotiated;
gboolean have_segment;
/* MT-protected (with STREAM_LOCK) */
GstSegment segment;
GMutex *transform_lock;
/*< private >*/
GstBaseTransformPrivate *priv;
gpointer _gst_reserved[GST_PADDING_LARGE];
};
/**
* GstBaseTransformClass:
* @parent_class: Element parent class
* @passthrough_on_same_caps: If set to TRUE, passthrough mode will be
* automatically enabled if the caps are the same.
* @transform_caps: Optional. Given the pad in this direction and the given
* caps, what caps are allowed on the other pad in this
* element ?
* @fixate_caps: Optional. Given the pad in this direction and the given
* caps, fixate the caps on the other pad.
* @accept_caps: Optional. Since 0.10.30
* Subclasses can override this method to check if @caps can be
* handled by the element. The default implementation might not be
* the most optimal way to check this in all cases.
* @set_caps: allows the subclass to be notified of the actual caps set.
* @transform_size: Optional. Given the size of a buffer in the given direction
* with the given caps, calculate the size in bytes of a buffer
* on the other pad with the given other caps.
* The default implementation uses get_unit_size and keeps
* the number of units the same.
* @get_unit_size: Required if the transform is not in-place.
* get the size in bytes of one unit for the given caps.
* @start: Optional.
* Called when the element starts processing.
* Allows opening external resources.
* @stop: Optional.
* Called when the element stops processing.
* Allows closing external resources.
* @transform: Required if the element does not operate in-place.
* Transforms one incoming buffer to one outgoing buffer.
* The function is allowed to change size/timestamp/duration
* of the outgoing buffer.
* @transform_ip: Required if the element operates in-place.
* Transform the incoming buffer in-place.
* @sink_event: Optional.
* Event handler on the sink pad. The default implementation
* handles the event and forwards it downstream.
* @src_event: Optional.
* Event handler on the source pad. The default implementation
* handles the event and forwards it upstream.
* @prepare_output_buffer: Optional.
* Subclasses can override this to do their own
* allocation of output buffers. Elements that only do
* analysis can return a subbuffer or even just
* return a reference to the input buffer (if in
* passthrough mode). The default implementation will
* use the negotiated allocator or bufferpool and
* transform_size to allocate an output buffer or it
* will return the input buffer in passthrough mode.
* @copy_metadata: Optional.
* Copy the metadata from the input buffer to the output buffer.
* The default implementation will copy the flags, timestamps and
* offsets of the buffer.
* @before_transform: Optional. Since 0.10.22
* This method is called right before the base class will
* start processing. Dynamic properties or other delayed
* configuration could be performed in this method.
*
* Subclasses can override any of the available virtual methods or not, as
* needed. At minimum either @transform or @transform_ip need to be overridden.
* If the element can overwrite the input data with the results (data is of the
* same type and quantity) it should provide @transform_ip.
*/
struct _GstBaseTransformClass {
GstElementClass parent_class;
/*< public >*/
gboolean passthrough_on_same_caps;
/* virtual methods for subclasses */
GstCaps* (*transform_caps) (GstBaseTransform *trans,
GstPadDirection direction,
GstCaps *caps, GstCaps *filter);
void (*fixate_caps) (GstBaseTransform *trans,
GstPadDirection direction, GstCaps *caps,
GstCaps *othercaps);
gboolean (*accept_caps) (GstBaseTransform *trans, GstPadDirection direction,
GstCaps *caps);
gboolean (*set_caps) (GstBaseTransform *trans, GstCaps *incaps,
GstCaps *outcaps);
/* setup allocation query */
gboolean (*setup_allocation) (GstBaseTransform *trans, GstQuery *query);
/* transform size */
gboolean (*transform_size) (GstBaseTransform *trans,
GstPadDirection direction,
GstCaps *caps, gsize size,
GstCaps *othercaps, gsize *othersize);
gboolean (*get_unit_size) (GstBaseTransform *trans, GstCaps *caps,
gsize *size);
/* states */
gboolean (*start) (GstBaseTransform *trans);
gboolean (*stop) (GstBaseTransform *trans);
/* sink and src pad event handlers */
gboolean (*sink_event) (GstBaseTransform *trans, GstEvent *event);
gboolean (*src_event) (GstBaseTransform *trans, GstEvent *event);
GstFlowReturn (*prepare_output_buffer) (GstBaseTransform * trans,
GstBuffer *input, GstBuffer **outbuf);
gboolean (*copy_metadata) (GstBaseTransform * trans, GstBuffer *input, GstBuffer *outbuf);
void (*before_transform) (GstBaseTransform *trans, GstBuffer *buffer);
/* transform */
GstFlowReturn (*transform) (GstBaseTransform *trans, GstBuffer *inbuf,
GstBuffer *outbuf);
GstFlowReturn (*transform_ip) (GstBaseTransform *trans, GstBuffer *buf);
/*< private >*/
gpointer _gst_reserved[GST_PADDING_LARGE];
};
GType gst_base_transform_get_type (void);
void gst_base_transform_set_passthrough (GstBaseTransform *trans,
gboolean passthrough);
gboolean gst_base_transform_is_passthrough (GstBaseTransform *trans);
void gst_base_transform_set_in_place (GstBaseTransform *trans,
gboolean in_place);
gboolean gst_base_transform_is_in_place (GstBaseTransform *trans);
void gst_base_transform_update_qos (GstBaseTransform *trans,
gdouble proportion,
GstClockTimeDiff diff,
GstClockTime timestamp);
void gst_base_transform_set_qos_enabled (GstBaseTransform *trans,
gboolean enabled);
gboolean gst_base_transform_is_qos_enabled (GstBaseTransform *trans);
void gst_base_transform_set_gap_aware (GstBaseTransform *trans,
gboolean gap_aware);
void gst_base_transform_suggest (GstBaseTransform *trans,
GstCaps *caps, gsize size);
void gst_base_transform_reconfigure (GstBaseTransform *trans);
G_END_DECLS
#endif /* __GST_BASE_TRANSFORM_H__ */