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/* 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 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.
* @query: Optional Since 0.10.36
* Handle a requested query. Subclasses that implement this
* should must chain up to the parent if they didn't handle the
* query
* @propose_allocation: Propose buffer allocation parameters for upstream elements.
* This function is only called when not operating in
* passthrough mode. The default implementation is NULL.
* @decide_allocation: Setup the allocation parameters for allocating output
* buffers. The passed in query contains the result of the
* downstream allocation query. This function is only called
* when not operating in passthrough mode. The default
* implementation is NULL.
* @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.
* @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.
* @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.
*
* 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);
gboolean (*query) (GstBaseTransform *trans, GstPadDirection direction,
GstQuery *query);
/* propose allocation query parameters for input buffers */
gboolean (*propose_allocation) (GstBaseTransform *trans, GstQuery *query);
/* decide allocation query for output buffers */
gboolean (*decide_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__ */
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