summaryrefslogtreecommitdiff
path: root/gst/gstelement.h
blob: 1d05451878e8efd99e3431e8c1eab77c7e2ea61d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wtay@chello.be>
 *
 * gstelement.h: Header for GstElement
 *
 * 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_ELEMENT_H__
#define __GST_ELEMENT_H__

#include <gst/gstconfig.h>

#include <gst/gstobject.h>
#include <gst/gstpad.h>
#include <gst/cothreads.h>
#include <gst/gstpluginfeature.h>

#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */


typedef enum {
  GST_STATE_VOID_PENDING	= 0,
  GST_STATE_NULL		= (1 << 0),
  GST_STATE_READY		= (1 << 1),
  GST_STATE_PAUSED		= (1 << 2),
  GST_STATE_PLAYING		= (1 << 3),
} GstElementState;

typedef enum {
  GST_STATE_FAILURE		= 0,
  GST_STATE_SUCCESS		= 1,
  GST_STATE_ASYNC		= 2,
} GstElementStateReturn;


// NOTE: this probably should be done with an #ifdef to decide whether to safe-cast
// or to just do the non-checking cast.
#define GST_STATE(obj)			(GST_ELEMENT(obj)->current_state)
#define GST_STATE_PENDING(obj)		(GST_ELEMENT(obj)->pending_state)

// Note: using 8 bit shift mostly "just because", it leaves us enough room to grow <g>
#define GST_STATE_TRANSITION(obj)	((GST_STATE(obj)<<8) | GST_STATE_PENDING(obj))
#define GST_STATE_NULL_TO_READY		((GST_STATE_NULL<<8) | GST_STATE_READY)
#define GST_STATE_READY_TO_PAUSED	((GST_STATE_READY<<8) | GST_STATE_PAUSED)
#define GST_STATE_PAUSED_TO_PLAYING	((GST_STATE_PAUSED<<8) | GST_STATE_PLAYING)
#define GST_STATE_PLAYING_TO_PAUSED	((GST_STATE_PLAYING<<8) | GST_STATE_PAUSED)
#define GST_STATE_PAUSED_TO_READY	((GST_STATE_PAUSED<<8) | GST_STATE_READY)
#define GST_STATE_READY_TO_NULL		((GST_STATE_READY<<8) | GST_STATE_NULL)

extern GType _gst_element_type;

#define GST_TYPE_ELEMENT		(_gst_element_type)

#define GST_ELEMENT_FAST(obj)		((GstElement*)(obj))
#define GST_ELEMENT_CLASS_FAST(klass)	((GstElementClass*)(klass))
#define GST_IS_ELEMENT(obj)		(G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_ELEMENT))
#define GST_IS_ELEMENT_CLASS(obj)	(G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_ELEMENT))

#ifdef GST_TYPE_PARANOID
# define GST_ELEMENT(obj)		(G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ELEMENT, GstElement))
# define GST_ELEMENT_CLASS(klass)       (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_ELEMENT, GstElementClass))
#else
# define GST_ELEMENT                    GST_ELEMENT_FAST
# define GST_ELEMENT_CLASS              GST_ELEMENT_CLASS_FAST
#endif

typedef enum {
  /* element is complex (for some def.) and generally require a cothread */
  GST_ELEMENT_COMPLEX		= GST_OBJECT_FLAG_LAST,
  /* input and output pads aren't directly coupled to each other
     examples: queues, multi-output async readers, etc. */
  GST_ELEMENT_DECOUPLED,
  /* this element should be placed in a thread if at all possible */
  GST_ELEMENT_THREAD_SUGGESTED,
  /* this element is incable of seeking (FIXME: does this apply to filters?) */
  GST_ELEMENT_NO_SEEK,

  /***** !!!!! need to have a flag that says that an element must
    *not* be an entry into a scheduling chain !!!!! *****/
  /* this element for some reason doesn't obey COTHREAD_STOPPING, or
     has some other reason why it can't be the entry */
  GST_ELEMENT_NO_ENTRY,

  /* there is a new loopfunction ready for placement */
  GST_ELEMENT_NEW_LOOPFUNC,
  /* the cothread holding this element needs to be stopped */
  GST_ELEMENT_COTHREAD_STOPPING,
  /* the element has to be scheduled as a cothread for any sanity */
  GST_ELEMENT_USE_COTHREAD,

  /* if this element is in EOS */
  GST_ELEMENT_EOS,

  /* use some padding for future expansion */
  GST_ELEMENT_FLAG_LAST		= GST_OBJECT_FLAG_LAST + 12,
} GstElementFlags;

#define GST_ELEMENT_IS_THREAD_SUGGESTED(obj)	(GST_FLAG_IS_SET(obj,GST_ELEMENT_THREAD_SUGGESTED))
#define GST_ELEMENT_IS_COTHREAD_STOPPING(obj)	(GST_FLAG_IS_SET(obj,GST_ELEMENT_COTHREAD_STOPPING))
#define GST_ELEMENT_IS_EOS(obj)			(GST_FLAG_IS_SET(obj,GST_ELEMENT_EOS))

#define GST_ELEMENT_NAME(obj)			(GST_OBJECT_NAME(obj))
#define GST_ELEMENT_PARENT(obj)			(GST_OBJECT_PARENT(obj))
#define GST_ELEMENT_MANAGER(obj)		(((GstElement*)(obj))->manager)
#define GST_ELEMENT_SCHED(obj)			(((GstElement*)(obj))->sched)
#define GST_ELEMENT_PADS(obj)			((obj)->pads)

//typedef struct _GstElement GstElement;
//typedef struct _GstElementClass GstElementClass;
typedef struct _GstElementFactory GstElementFactory;
typedef struct _GstElementFactoryClass GstElementFactoryClass;

typedef void (*GstElementLoopFunction) (GstElement *element);

struct _GstElement {
  GstObject 		object;

  /* element state  and scheduling */
  guint8 		current_state;
  guint8 		pending_state;
  GstElement 		*manager;
  GstSchedule 		*sched;
  GstElementLoopFunction loopfunc;
  cothread_state 	*threadstate;

  /* element pads */
  guint16 		numpads;
  guint16 		numsrcpads;
  guint16 		numsinkpads;
  GList 		*pads;
  GstPad 		*select_pad;
};

struct _GstElementClass {
  GstObjectClass 	parent_class;

  /* the elementfactory that created us */
  GstElementFactory 	*elementfactory;
  /* templates for our pads */
  GList 		*padtemplates;
  gint 			numpadtemplates;
  
  /* signal callbacks */
  void (*state_change)		(GstElement *element,GstElementState state);
  void (*new_pad)		(GstElement *element,GstPad *pad);
  void (*pad_removed)		(GstElement *element,GstPad *pad);
  void (*new_ghost_pad) 	(GstElement *element,GstPad *pad);
  void (*ghost_pad_removed)	(GstElement *element,GstPad *pad);
  void (*error)			(GstElement *element,gchar *error);
  void (*eos)			(GstElement *element);

  /* local pointers for get/set */
  void (*set_property) 	(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
  void (*get_property)	(GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);

  /* change the element state */
  GstElementStateReturn (*change_state)		(GstElement *element);
  /* request a new pad */
  GstPad*		(*request_new_pad)	(GstElement *element, GstPadTemplate *templ, const gchar* name);
};

void			gst_element_class_add_padtemplate	(GstElementClass *element, GstPadTemplate *templ);

GType			gst_element_get_type		(void);
#define			gst_element_destroy(element)	gst_object_destroy (GST_OBJECT (element))

void			gst_element_set_loop_function	(GstElement *element,
							 GstElementLoopFunction loop);

void                    gst_element_set_name            (GstElement *element, const gchar *name);
const gchar*            gst_element_get_name            (GstElement *element);

void                    gst_element_set_parent          (GstElement *element, GstObject *parent);
GstObject*              gst_element_get_parent          (GstElement *element);

void			gst_element_set_sched		(GstElement *element, GstSchedule *sched);
GstSchedule*		gst_element_get_sched		(GstElement *element);

void			gst_element_add_pad		(GstElement *element, GstPad *pad);
void			gst_element_remove_pad		(GstElement *element, GstPad *pad);
GstPad*			gst_element_get_pad		(GstElement *element, const gchar *name);
GList*			gst_element_get_pad_list	(GstElement *element);
GList*			gst_element_get_padtemplate_list	(GstElement *element);
GstPadTemplate*		gst_element_get_padtemplate_by_name	(GstElement *element, const guchar *name);
void			gst_element_add_ghost_pad	(GstElement *element, GstPad *pad, gchar *name);
void			gst_element_remove_ghost_pad	(GstElement *element, GstPad *pad);

GstPad*			gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ);
GstPad*			gst_element_request_pad_by_name	(GstElement *element, const gchar *name);

void			gst_element_connect		(GstElement *src, const gchar *srcpadname,
							 GstElement *dest, const gchar *destpadname);
void			gst_element_disconnect		(GstElement *src, const gchar *srcpadname,
							 GstElement *dest, const gchar *destpadname);

void			gst_element_signal_eos		(GstElement *element);


GstElementState         gst_element_get_state           (GstElement *elem);
/* called by the app to set the state of the element */
gint			gst_element_set_state		(GstElement *element, GstElementState state);
const gchar *		gst_element_statename		(GstElementState state);

void			gst_element_error		(GstElement *element, const gchar *error);

GstElementFactory*	gst_element_get_factory		(GstElement *element);

#ifndef GST_DISABLE_LOADSAVE
/* XML write and read */
GstElement*		gst_element_restore_thyself	(xmlNodePtr self, GstObject *parent);
#endif


/*
 *
 * factories stuff
 *
 **/
typedef struct _GstElementDetails GstElementDetails;

struct _GstElementDetails {
  gchar *longname;              /* long, english name */
  gchar *klass;                 /* type of element, as hierarchy */
  gchar *description;           /* insights of one form or another */
  gchar *version;               /* version of the element */
  gchar *author;                /* who wrote this thing? */
  gchar *copyright;             /* copyright details (year, etc.) */
};

#define GST_TYPE_ELEMENTFACTORY 		(gst_elementfactory_get_type())
#define GST_ELEMENTFACTORY(obj)  		(G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_ELEMENTFACTORY,\
						 GstElementFactory))
#define GST_ELEMENTFACTORY_CLASS(klass) 	(G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_ELEMENTFACTORY,\
						 GstElementFactoryClass))
#define GST_IS_ELEMENTFACTORY(obj) 		(G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_ELEMENTFACTORY))
#define GST_IS_ELEMENTFACTORY_CLASS(klass) 	(G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_ELEMENTFACTORY))

struct _GstElementFactory {
  GstPluginFeature feature;

  GType type;			/* unique GType of element */

  guint details_dynamic : 1;

  GstElementDetails *details;	/* pointer to details struct */

  GList *padtemplates;
  guint16 numpadtemplates;
};

struct _GstElementFactoryClass {
  GstPluginFeatureClass parent_class;
};

GType 			gst_elementfactory_get_type 		(void);

GstElementFactory*	gst_elementfactory_new			(const gchar *name,GType type,
                                                                 GstElementDetails *details);

GstElementFactory*	gst_elementfactory_find			(const gchar *name);
const GList*		gst_elementfactory_get_list		(void);

void			gst_elementfactory_add_padtemplate	(GstElementFactory *elementfactory,
								 GstPadTemplate *templ);

gboolean		gst_elementfactory_can_src_caps		(GstElementFactory *factory,
								 GstCaps *caps);
gboolean		gst_elementfactory_can_sink_caps	(GstElementFactory *factory,
								 GstCaps *caps);

GstElement*		gst_elementfactory_create		(GstElementFactory *factory,
								 const gchar *name);
/* FIXME this name is wrong, probably so is the one above it */
GstElement*		gst_elementfactory_make			(const gchar *factoryname, const gchar *name);


#ifdef __cplusplus
}
#endif /* __cplusplus */


#endif /* __GST_ELEMENT_H__ */