1 /* GStreamer
2 * Copyright (C) <2006> Lutz Mueller <lutz at topfrose dot de>
3 * <2006> Wim Taymans <wim@fluendo.com>
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 */
20
21 #ifdef HAVE_CONFIG_H
22 # include "config.h"
23 #endif
24
25 #include <string.h>
26
27 #include "gstrdtbuffer.h"
28 #include "rdtdepay.h"
29
30 GST_DEBUG_CATEGORY_STATIC (rdtdepay_debug);
31 #define GST_CAT_DEFAULT rdtdepay_debug
32
33 /* RDTDepay signals and args */
34 enum
35 {
36 /* FILL ME */
37 LAST_SIGNAL
38 };
39
40 enum
41 {
42 PROP_0,
43 };
44
45 static GstStaticPadTemplate gst_rdt_depay_src_template =
46 GST_STATIC_PAD_TEMPLATE ("src",
47 GST_PAD_SRC,
48 GST_PAD_ALWAYS,
49 GST_STATIC_CAPS ("application/vnd.rn-realmedia")
50 );
51
52 static GstStaticPadTemplate gst_rdt_depay_sink_template =
53 GST_STATIC_PAD_TEMPLATE ("sink",
54 GST_PAD_SINK,
55 GST_PAD_ALWAYS,
56 GST_STATIC_CAPS ("application/x-rdt, "
57 "media = (string) \"application\", "
58 "clock-rate = (int) [1, MAX ], "
59 "encoding-name = (string) \"X-REAL-RDT\""
60 /* All optional parameters
61 *
62 * "config="
63 */
64 )
65 );
66
67 #define gst_rdt_depay_parent_class parent_class
68 G_DEFINE_TYPE (GstRDTDepay, gst_rdt_depay, GST_TYPE_ELEMENT);
69
70 static void gst_rdt_depay_finalize (GObject * object);
71
72 static GstStateChangeReturn gst_rdt_depay_change_state (GstElement *
73 element, GstStateChange transition);
74
75 static gboolean gst_rdt_depay_sink_event (GstPad * pad, GstObject * parent,
76 GstEvent * event);
77 static GstFlowReturn gst_rdt_depay_chain (GstPad * pad, GstObject * parent,
78 GstBuffer * buf);
79
80 static void
gst_rdt_depay_class_init(GstRDTDepayClass * klass)81 gst_rdt_depay_class_init (GstRDTDepayClass * klass)
82 {
83 GObjectClass *gobject_class;
84 GstElementClass *gstelement_class;
85
86 gobject_class = (GObjectClass *) klass;
87 gstelement_class = (GstElementClass *) klass;
88
89 parent_class = g_type_class_peek_parent (klass);
90
91 gobject_class->finalize = gst_rdt_depay_finalize;
92
93 gstelement_class->change_state = gst_rdt_depay_change_state;
94
95 gst_element_class_add_static_pad_template (gstelement_class,
96 &gst_rdt_depay_src_template);
97 gst_element_class_add_static_pad_template (gstelement_class,
98 &gst_rdt_depay_sink_template);
99
100 gst_element_class_set_static_metadata (gstelement_class, "RDT packet parser",
101 "Codec/Depayloader/Network",
102 "Extracts RealMedia from RDT packets",
103 "Lutz Mueller <lutz at topfrose dot de>, "
104 "Wim Taymans <wim@fluendo.com>");
105
106 GST_DEBUG_CATEGORY_INIT (rdtdepay_debug, "rdtdepay",
107 0, "Depayloader for RDT RealMedia packets");
108 }
109
110 static void
gst_rdt_depay_init(GstRDTDepay * rdtdepay)111 gst_rdt_depay_init (GstRDTDepay * rdtdepay)
112 {
113 rdtdepay->sinkpad =
114 gst_pad_new_from_static_template (&gst_rdt_depay_sink_template, "sink");
115 gst_pad_set_chain_function (rdtdepay->sinkpad, gst_rdt_depay_chain);
116 gst_pad_set_event_function (rdtdepay->sinkpad, gst_rdt_depay_sink_event);
117 gst_element_add_pad (GST_ELEMENT_CAST (rdtdepay), rdtdepay->sinkpad);
118
119 rdtdepay->srcpad =
120 gst_pad_new_from_static_template (&gst_rdt_depay_src_template, "src");
121 gst_element_add_pad (GST_ELEMENT_CAST (rdtdepay), rdtdepay->srcpad);
122 }
123
124 static void
gst_rdt_depay_finalize(GObject * object)125 gst_rdt_depay_finalize (GObject * object)
126 {
127 GstRDTDepay *rdtdepay;
128
129 rdtdepay = GST_RDT_DEPAY (object);
130
131 if (rdtdepay->header)
132 gst_buffer_unref (rdtdepay->header);
133
134 G_OBJECT_CLASS (parent_class)->finalize (object);
135 }
136
137 static gboolean
gst_rdt_depay_setcaps(GstPad * pad,GstCaps * caps)138 gst_rdt_depay_setcaps (GstPad * pad, GstCaps * caps)
139 {
140 GstStructure *structure;
141 GstRDTDepay *rdtdepay;
142 GstCaps *srccaps;
143 gint clock_rate = 1000; /* default */
144 const GValue *value;
145 GstBuffer *header;
146
147 rdtdepay = GST_RDT_DEPAY (GST_PAD_PARENT (pad));
148
149 structure = gst_caps_get_structure (caps, 0);
150
151 if (gst_structure_has_field (structure, "clock-rate"))
152 gst_structure_get_int (structure, "clock-rate", &clock_rate);
153
154 /* config contains the RealMedia header as a buffer. */
155 value = gst_structure_get_value (structure, "config");
156 if (!value)
157 goto no_header;
158
159 header = gst_value_get_buffer (value);
160 if (!header)
161 goto no_header;
162
163 /* get other values for newsegment */
164 value = gst_structure_get_value (structure, "npt-start");
165 if (value && G_VALUE_HOLDS_UINT64 (value))
166 rdtdepay->npt_start = g_value_get_uint64 (value);
167 else
168 rdtdepay->npt_start = 0;
169 GST_DEBUG_OBJECT (rdtdepay, "NPT start %" G_GUINT64_FORMAT,
170 rdtdepay->npt_start);
171
172 value = gst_structure_get_value (structure, "npt-stop");
173 if (value && G_VALUE_HOLDS_UINT64 (value))
174 rdtdepay->npt_stop = g_value_get_uint64 (value);
175 else
176 rdtdepay->npt_stop = -1;
177
178 GST_DEBUG_OBJECT (rdtdepay, "NPT stop %" G_GUINT64_FORMAT,
179 rdtdepay->npt_stop);
180
181 value = gst_structure_get_value (structure, "play-speed");
182 if (value && G_VALUE_HOLDS_DOUBLE (value))
183 rdtdepay->play_speed = g_value_get_double (value);
184 else
185 rdtdepay->play_speed = 1.0;
186
187 value = gst_structure_get_value (structure, "play-scale");
188 if (value && G_VALUE_HOLDS_DOUBLE (value))
189 rdtdepay->play_scale = g_value_get_double (value);
190 else
191 rdtdepay->play_scale = 1.0;
192
193 /* caps seem good, configure element */
194 rdtdepay->clock_rate = clock_rate;
195
196 /* set caps on pad and on header */
197 srccaps = gst_caps_new_empty_simple ("application/vnd.rn-realmedia");
198 gst_pad_set_caps (rdtdepay->srcpad, srccaps);
199 gst_caps_unref (srccaps);
200
201 if (rdtdepay->header)
202 gst_buffer_unref (rdtdepay->header);
203 rdtdepay->header = gst_buffer_ref (header);
204
205 return TRUE;
206
207 /* ERRORS */
208 no_header:
209 {
210 GST_ERROR_OBJECT (rdtdepay, "no header found in caps, no 'config' field");
211 return FALSE;
212 }
213 }
214
215 static gboolean
gst_rdt_depay_sink_event(GstPad * pad,GstObject * parent,GstEvent * event)216 gst_rdt_depay_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
217 {
218 GstRDTDepay *depay;
219 gboolean res = TRUE;
220
221 depay = GST_RDT_DEPAY (parent);
222
223 switch (GST_EVENT_TYPE (event)) {
224 case GST_EVENT_CAPS:
225 {
226 GstCaps *caps;
227
228 gst_event_parse_caps (event, &caps);
229 res = gst_rdt_depay_setcaps (pad, caps);
230 gst_event_unref (event);
231 break;
232 }
233 case GST_EVENT_FLUSH_STOP:
234 res = gst_pad_push_event (depay->srcpad, event);
235
236 gst_segment_init (&depay->segment, GST_FORMAT_UNDEFINED);
237 depay->need_newsegment = TRUE;
238 depay->next_seqnum = -1;
239 break;
240 case GST_EVENT_SEGMENT:
241 {
242 gst_event_copy_segment (event, &depay->segment);
243 /* don't pass the event downstream, we generate our own segment
244 * including the NTP time and other things we receive in caps */
245 gst_event_unref (event);
246 break;
247 }
248 default:
249 /* pass other events forward */
250 res = gst_pad_push_event (depay->srcpad, event);
251 break;
252 }
253 return res;
254 }
255
256 static GstEvent *
create_segment_event(GstRDTDepay * depay,gboolean update,GstClockTime position)257 create_segment_event (GstRDTDepay * depay, gboolean update,
258 GstClockTime position)
259 {
260 GstSegment segment;
261
262 gst_segment_init (&segment, GST_FORMAT_TIME);
263 segment.rate = depay->play_speed;
264 segment.applied_rate = depay->play_scale;
265 segment.start = position;
266
267 if (depay->npt_stop != -1)
268 segment.stop = depay->npt_stop - depay->npt_start;
269 else
270 segment.stop = -1;
271
272 segment.time = position + depay->npt_start;
273
274 return gst_event_new_segment (&segment);
275 }
276
277 static GstFlowReturn
gst_rdt_depay_push(GstRDTDepay * rdtdepay,GstBuffer * buffer)278 gst_rdt_depay_push (GstRDTDepay * rdtdepay, GstBuffer * buffer)
279 {
280 GstFlowReturn ret;
281
282 if (rdtdepay->need_newsegment) {
283 GstEvent *event;
284
285 event = create_segment_event (rdtdepay, FALSE, 0);
286 gst_pad_push_event (rdtdepay->srcpad, event);
287
288 rdtdepay->need_newsegment = FALSE;
289 }
290
291 if (rdtdepay->discont) {
292 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DISCONT);
293 rdtdepay->discont = FALSE;
294 }
295 ret = gst_pad_push (rdtdepay->srcpad, buffer);
296
297 return ret;
298 }
299
300 static GstFlowReturn
gst_rdt_depay_handle_data(GstRDTDepay * rdtdepay,GstClockTime outtime,GstRDTPacket * packet)301 gst_rdt_depay_handle_data (GstRDTDepay * rdtdepay, GstClockTime outtime,
302 GstRDTPacket * packet)
303 {
304 GstFlowReturn ret;
305 GstBuffer *outbuf;
306 GstMapInfo outmap;
307 guint8 *data, *outdata;
308 guint size;
309 guint16 stream_id;
310 guint32 timestamp;
311 gint gap;
312 guint16 seqnum;
313 guint8 flags;
314 guint16 outflags;
315
316 /* get pointers to the packet data */
317 data = gst_rdt_packet_data_map (packet, &size);
318
319 outbuf = gst_buffer_new_and_alloc (12 + size);
320 GST_BUFFER_TIMESTAMP (outbuf) = outtime;
321
322 GST_DEBUG_OBJECT (rdtdepay, "have size %u", size);
323
324 /* copy over some things */
325 stream_id = gst_rdt_packet_data_get_stream_id (packet);
326 timestamp = gst_rdt_packet_data_get_timestamp (packet);
327 flags = gst_rdt_packet_data_get_flags (packet);
328
329 seqnum = gst_rdt_packet_data_get_seq (packet);
330
331 GST_DEBUG_OBJECT (rdtdepay, "stream_id %u, timestamp %u, seqnum %d, flags %d",
332 stream_id, timestamp, seqnum, flags);
333
334 if (rdtdepay->next_seqnum != -1) {
335 gap = gst_rdt_buffer_compare_seqnum (seqnum, rdtdepay->next_seqnum);
336
337 /* if we have no gap, all is fine */
338 if (G_UNLIKELY (gap != 0)) {
339 GST_LOG_OBJECT (rdtdepay, "got packet %u, expected %u, gap %d", seqnum,
340 rdtdepay->next_seqnum, gap);
341 if (gap < 0) {
342 /* seqnum > next_seqnum, we are missing some packets, this is always a
343 * DISCONT. */
344 GST_LOG_OBJECT (rdtdepay, "%d missing packets", gap);
345 rdtdepay->discont = TRUE;
346 } else {
347 /* seqnum < next_seqnum, we have seen this packet before or the sender
348 * could be restarted. If the packet is not too old, we throw it away as
349 * a duplicate, otherwise we mark discont and continue. 100 misordered
350 * packets is a good threshold. See also RFC 4737. */
351 if (gap < 100)
352 goto dropping;
353
354 GST_LOG_OBJECT (rdtdepay,
355 "%d > 100, packet too old, sender likely restarted", gap);
356 rdtdepay->discont = TRUE;
357 }
358 }
359 }
360 rdtdepay->next_seqnum = (seqnum + 1);
361 if (rdtdepay->next_seqnum == 0xff00)
362 rdtdepay->next_seqnum = 0;
363
364 if ((flags & 1) == 0)
365 outflags = 2;
366 else
367 outflags = 0;
368
369 gst_buffer_map (outbuf, &outmap, GST_MAP_WRITE);
370 outdata = outmap.data;
371 GST_WRITE_UINT16_BE (outdata + 0, 0); /* version */
372 GST_WRITE_UINT16_BE (outdata + 2, size + 12); /* length */
373 GST_WRITE_UINT16_BE (outdata + 4, stream_id); /* stream */
374 GST_WRITE_UINT32_BE (outdata + 6, timestamp); /* timestamp */
375 GST_WRITE_UINT16_BE (outdata + 10, outflags); /* flags */
376 memcpy (outdata + 12, data, size);
377 gst_buffer_unmap (outbuf, &outmap);
378 gst_buffer_resize (outbuf, 0, 12 + size);
379
380 gst_rdt_packet_data_unmap (packet);
381
382 GST_DEBUG_OBJECT (rdtdepay, "Pushing packet, outtime %" GST_TIME_FORMAT,
383 GST_TIME_ARGS (outtime));
384
385 ret = gst_rdt_depay_push (rdtdepay, outbuf);
386
387 return ret;
388
389 /* ERRORS */
390 dropping:
391 {
392 GST_WARNING_OBJECT (rdtdepay, "%d <= 100, dropping old packet", gap);
393 return GST_FLOW_OK;
394 }
395 }
396
397 static GstFlowReturn
gst_rdt_depay_chain(GstPad * pad,GstObject * parent,GstBuffer * buf)398 gst_rdt_depay_chain (GstPad * pad, GstObject * parent, GstBuffer * buf)
399 {
400 GstRDTDepay *rdtdepay;
401 GstFlowReturn ret;
402 GstClockTime timestamp;
403 gboolean more;
404 GstRDTPacket packet;
405
406 rdtdepay = GST_RDT_DEPAY (parent);
407
408 if (GST_BUFFER_IS_DISCONT (buf)) {
409 GST_LOG_OBJECT (rdtdepay, "received discont");
410 rdtdepay->discont = TRUE;
411 }
412
413 if (rdtdepay->header) {
414 GstBuffer *out;
415
416 out = rdtdepay->header;
417 rdtdepay->header = NULL;
418
419 /* push header data first */
420 gst_rdt_depay_push (rdtdepay, out);
421 }
422
423 /* save timestamp */
424 timestamp = GST_BUFFER_TIMESTAMP (buf);
425
426 ret = GST_FLOW_OK;
427
428 GST_LOG_OBJECT (rdtdepay, "received buffer timestamp %" GST_TIME_FORMAT,
429 GST_TIME_ARGS (timestamp));
430
431 /* data is in RDT format. */
432 more = gst_rdt_buffer_get_first_packet (buf, &packet);
433 while (more) {
434 GstRDTType type;
435
436 type = gst_rdt_packet_get_type (&packet);
437 GST_DEBUG_OBJECT (rdtdepay, "Have packet of type %04x", type);
438
439 if (GST_RDT_IS_DATA_TYPE (type)) {
440 GST_DEBUG_OBJECT (rdtdepay, "We have a data packet");
441 ret = gst_rdt_depay_handle_data (rdtdepay, timestamp, &packet);
442 } else {
443 switch (type) {
444 default:
445 GST_DEBUG_OBJECT (rdtdepay, "Ignoring packet");
446 break;
447 }
448 }
449 if (ret != GST_FLOW_OK)
450 break;
451
452 more = gst_rdt_packet_move_to_next (&packet);
453 }
454
455 gst_buffer_unref (buf);
456
457 return ret;
458 }
459
460 static GstStateChangeReturn
gst_rdt_depay_change_state(GstElement * element,GstStateChange transition)461 gst_rdt_depay_change_state (GstElement * element, GstStateChange transition)
462 {
463 GstRDTDepay *rdtdepay;
464 GstStateChangeReturn ret;
465
466 rdtdepay = GST_RDT_DEPAY (element);
467
468 switch (transition) {
469 case GST_STATE_CHANGE_NULL_TO_READY:
470 break;
471 case GST_STATE_CHANGE_READY_TO_PAUSED:
472 gst_segment_init (&rdtdepay->segment, GST_FORMAT_UNDEFINED);
473 rdtdepay->next_seqnum = -1;
474 rdtdepay->need_newsegment = TRUE;
475 break;
476 default:
477 break;
478 }
479
480 ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
481
482 switch (transition) {
483 case GST_STATE_CHANGE_PAUSED_TO_READY:
484 if (rdtdepay->header)
485 gst_buffer_unref (rdtdepay->header);
486 rdtdepay->header = NULL;
487 break;
488 case GST_STATE_CHANGE_READY_TO_NULL:
489 break;
490 default:
491 break;
492 }
493 return ret;
494 }
495
496 gboolean
gst_rdt_depay_plugin_init(GstPlugin * plugin)497 gst_rdt_depay_plugin_init (GstPlugin * plugin)
498 {
499 return gst_element_register (plugin, "rdtdepay",
500 GST_RANK_MARGINAL, GST_TYPE_RDT_DEPAY);
501 }
502