2 * gstcmmlenc.c - GStreamer CMML encoder
3 * Copyright (C) 2005 Alessandro Decina
6 * Alessandro Decina <alessandro@nnva.org>
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Library General Public
10 * License as published by the Free Software Foundation; either
11 * version 2 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Library General Public License for more details.
18 * You should have received a copy of the GNU Library General Public
19 * License along with this library; if not, write to the
20 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
21 * Boston, MA 02111-1307, USA.
25 * SECTION:element-cmmlenc
26 * @see_also: cmmldec, oggmux
28 * Cmmlenc encodes a CMML document into a CMML stream. <ulink
29 * url="http://www.annodex.net/TR/draft-pfeiffer-cmml-02.html">CMML</ulink> is
30 * an XML markup language for time-continuous data maintained by the <ulink
31 * url="http:/www.annodex.org/">Annodex Foundation</ulink>.
34 * <title>Example pipeline</title>
36 * gst-launch -v filesrc location=annotations.cmml ! cmmlenc ! oggmux name=mux ! filesink location=annotated.ogg
47 #include "gstcmmlenc.h"
48 #include "gstannodex.h"
50 GST_DEBUG_CATEGORY_STATIC (cmmlenc);
51 #define GST_CAT_DEFAULT cmmlenc
53 #define CMML_IDENT_HEADER_SIZE 29
58 GST_CMML_ENC_GRANULERATE_N,
59 GST_CMML_ENC_GRANULERATE_D,
60 GST_CMML_ENC_GRANULESHIFT
68 static GstStaticPadTemplate gst_cmml_enc_src_factory =
69 GST_STATIC_PAD_TEMPLATE ("src",
72 GST_STATIC_CAPS ("text/x-cmml, encoded = (boolean) true")
75 static GstStaticPadTemplate gst_cmml_enc_sink_factory =
76 GST_STATIC_PAD_TEMPLATE ("sink",
79 GST_STATIC_CAPS ("text/x-cmml, encoded = (boolean) false")
82 GST_BOILERPLATE (GstCmmlEnc, gst_cmml_enc, GstElement, GST_TYPE_ELEMENT);
83 static void gst_cmml_enc_get_property (GObject * object, guint property_id,
84 GValue * value, GParamSpec * pspec);
85 static void gst_cmml_enc_set_property (GObject * object, guint property_id,
86 const GValue * value, GParamSpec * pspec);
87 static gboolean gst_cmml_enc_sink_event (GstPad * pad, GstEvent * event);
88 static GstStateChangeReturn gst_cmml_enc_change_state (GstElement * element,
89 GstStateChange transition);
90 static GstFlowReturn gst_cmml_enc_chain (GstPad * pad, GstBuffer * buffer);
91 static void gst_cmml_enc_parse_preamble (GstCmmlEnc * enc,
92 guchar * preamble, guchar * processing_instruction);
93 static void gst_cmml_enc_parse_end_tag (GstCmmlEnc * enc);
94 static void gst_cmml_enc_parse_tag_head (GstCmmlEnc * enc,
95 GstCmmlTagHead * head);
96 static void gst_cmml_enc_parse_tag_clip (GstCmmlEnc * enc,
97 GstCmmlTagClip * tag);
98 static GstFlowReturn gst_cmml_enc_new_buffer (GstCmmlEnc * enc,
99 guchar * data, gint size, GstBuffer ** buffer);
100 static GstFlowReturn gst_cmml_enc_push_clip (GstCmmlEnc * enc,
101 GstCmmlTagClip * clip, GstClockTime prev_clip_time);
102 static GstFlowReturn gst_cmml_enc_push (GstCmmlEnc * enc, GstBuffer * buffer);
104 static void gst_cmml_enc_finalize (GObject * object);
107 gst_cmml_enc_base_init (gpointer g_class)
109 GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);
111 gst_element_class_add_static_pad_template (element_class,
112 &gst_cmml_enc_sink_factory);
113 gst_element_class_add_static_pad_template (element_class,
114 &gst_cmml_enc_src_factory);
115 gst_element_class_set_details_simple (element_class, "CMML streams encoder",
117 "Encodes CMML streams", "Alessandro Decina <alessandro@nnva.org>");
121 gst_cmml_enc_class_init (GstCmmlEncClass * enc_class)
123 GObjectClass *klass = G_OBJECT_CLASS (enc_class);
125 klass->get_property = gst_cmml_enc_get_property;
126 klass->set_property = gst_cmml_enc_set_property;
127 klass->finalize = gst_cmml_enc_finalize;
129 g_object_class_install_property (klass, GST_CMML_ENC_GRANULERATE_N,
130 g_param_spec_int64 ("granule-rate-numerator",
131 "Granulerate numerator",
132 "Granulerate numerator",
134 G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
136 g_object_class_install_property (klass, GST_CMML_ENC_GRANULERATE_D,
137 g_param_spec_int64 ("granule-rate-denominator",
138 "Granulerate denominator",
139 "Granulerate denominator",
141 G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
143 g_object_class_install_property (klass, GST_CMML_ENC_GRANULESHIFT,
144 g_param_spec_uchar ("granule-shift",
146 "The number of lower bits to use for partitioning a granule position",
148 G_PARAM_READWRITE | G_PARAM_CONSTRUCT | G_PARAM_STATIC_STRINGS));
150 GST_ELEMENT_CLASS (klass)->change_state = gst_cmml_enc_change_state;
154 gst_cmml_enc_init (GstCmmlEnc * enc, GstCmmlEncClass * klass)
157 gst_pad_new_from_static_template (&gst_cmml_enc_sink_factory, "sink");
158 gst_pad_set_chain_function (enc->sinkpad, gst_cmml_enc_chain);
159 gst_pad_set_event_function (enc->sinkpad, gst_cmml_enc_sink_event);
160 gst_element_add_pad (GST_ELEMENT (enc), enc->sinkpad);
163 gst_pad_new_from_static_template (&gst_cmml_enc_src_factory, "src");
164 gst_element_add_pad (GST_ELEMENT (enc), enc->srcpad);
171 gst_cmml_enc_set_property (GObject * object, guint property_id,
172 const GValue * value, GParamSpec * pspec)
174 GstCmmlEnc *enc = GST_CMML_ENC (object);
176 switch (property_id) {
177 case GST_CMML_ENC_GRANULERATE_N:
178 /* XXX: may need to flush clips */
179 enc->granulerate_n = g_value_get_int64 (value);
181 case GST_CMML_ENC_GRANULERATE_D:
182 enc->granulerate_d = g_value_get_int64 (value);
184 case GST_CMML_ENC_GRANULESHIFT:
185 enc->granuleshift = g_value_get_uchar (value);
188 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
193 gst_cmml_enc_get_property (GObject * object, guint property_id,
194 GValue * value, GParamSpec * pspec)
196 GstCmmlEnc *enc = GST_CMML_ENC (object);
198 switch (property_id) {
199 case GST_CMML_ENC_GRANULERATE_N:
200 g_value_set_int64 (value, enc->granulerate_n);
202 case GST_CMML_ENC_GRANULERATE_D:
203 g_value_set_int64 (value, enc->granulerate_d);
205 case GST_CMML_ENC_GRANULESHIFT:
206 g_value_set_uchar (value, enc->granuleshift);
209 G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
214 gst_cmml_enc_finalize (GObject * object)
216 GstCmmlEnc *enc = GST_CMML_ENC (object);
219 gst_cmml_track_list_destroy (enc->tracks);
223 G_OBJECT_CLASS (parent_class)->finalize (object);
226 static GstStateChangeReturn
227 gst_cmml_enc_change_state (GstElement * element, GstStateChange transition)
229 GstCmmlEnc *enc = GST_CMML_ENC (element);
230 GstStateChangeReturn res;
232 switch (transition) {
233 case GST_STATE_CHANGE_READY_TO_PAUSED:
234 enc->parser = gst_cmml_parser_new (GST_CMML_PARSER_ENCODE);
235 enc->parser->user_data = enc;
236 enc->parser->preamble_callback =
237 (GstCmmlParserPreambleCallback) gst_cmml_enc_parse_preamble;
238 enc->parser->head_callback =
239 (GstCmmlParserHeadCallback) gst_cmml_enc_parse_tag_head;
240 enc->parser->clip_callback =
241 (GstCmmlParserClipCallback) gst_cmml_enc_parse_tag_clip;
242 enc->parser->cmml_end_callback =
243 (GstCmmlParserCmmlEndCallback) gst_cmml_enc_parse_end_tag;
244 enc->tracks = gst_cmml_track_list_new ();
245 enc->sent_headers = FALSE;
246 enc->sent_eos = FALSE;
247 enc->flow_return = GST_FLOW_OK;
253 res = parent_class->change_state (element, transition);
255 switch (transition) {
256 case GST_STATE_CHANGE_PAUSED_TO_READY:
258 gst_cmml_track_list_destroy (enc->tracks);
260 g_free (enc->preamble);
261 enc->preamble = NULL;
262 gst_cmml_parser_free (enc->parser);
273 gst_cmml_enc_sink_event (GstPad * pad, GstEvent * event)
275 GstCmmlEnc *enc = GST_CMML_ENC (GST_PAD_PARENT (pad));
277 switch (GST_EVENT_TYPE (event)) {
281 gst_cmml_enc_parse_end_tag (enc);
289 return gst_pad_event_default (pad, event);
293 gst_cmml_enc_new_buffer (GstCmmlEnc * enc,
294 guchar * data, gint size, GstBuffer ** buffer)
298 res = gst_pad_alloc_buffer (enc->srcpad, GST_BUFFER_OFFSET_NONE, size,
300 if (res == GST_FLOW_OK) {
302 memcpy (GST_BUFFER_DATA (*buffer), data, size);
304 GST_WARNING_OBJECT (enc, "alloc function returned error %s",
305 gst_flow_get_name (res));
312 gst_cmml_enc_set_header_on_caps (GstCmmlEnc * enc, GstCaps * caps,
313 GstBuffer * ident, GstBuffer * preamble, GstBuffer * head)
315 GValue array = { 0 };
316 GValue value = { 0 };
317 GstStructure *structure;
320 caps = gst_caps_make_writable (caps);
321 structure = gst_caps_get_structure (caps, 0);
323 g_value_init (&array, GST_TYPE_ARRAY);
324 g_value_init (&value, GST_TYPE_BUFFER);
326 /* Make copies of header buffers to avoid circular references */
327 buffer = gst_buffer_copy (ident);
328 gst_value_set_buffer (&value, buffer);
329 gst_value_array_append_value (&array, &value);
330 gst_buffer_unref (buffer);
332 buffer = gst_buffer_copy (preamble);
333 gst_value_set_buffer (&value, buffer);
334 gst_value_array_append_value (&array, &value);
335 gst_buffer_unref (buffer);
337 buffer = gst_buffer_copy (head);
338 gst_value_set_buffer (&value, buffer);
339 gst_value_array_append_value (&array, &value);
340 gst_buffer_unref (buffer);
342 GST_BUFFER_FLAG_SET (ident, GST_BUFFER_FLAG_IN_CAPS);
343 GST_BUFFER_FLAG_SET (preamble, GST_BUFFER_FLAG_IN_CAPS);
344 GST_BUFFER_FLAG_SET (head, GST_BUFFER_FLAG_IN_CAPS);
346 gst_structure_set_value (structure, "streamheader", &array);
348 g_value_unset (&value);
349 g_value_unset (&array);
354 /* create a CMML ident header buffer
357 gst_cmml_enc_new_ident_header (GstCmmlEnc * enc, GstBuffer ** buffer)
359 guint8 ident_header[CMML_IDENT_HEADER_SIZE];
360 guint8 *wptr = ident_header;
362 memcpy (wptr, "CMML\0\0\0\0", 8);
364 GST_WRITE_UINT16_LE (wptr, enc->major);
366 GST_WRITE_UINT16_LE (wptr, enc->minor);
368 GST_WRITE_UINT64_LE (wptr, enc->granulerate_n);
370 GST_WRITE_UINT64_LE (wptr, enc->granulerate_d);
372 *wptr = enc->granuleshift;
374 return gst_cmml_enc_new_buffer (enc,
375 (guchar *) & ident_header, CMML_IDENT_HEADER_SIZE, buffer);
378 /* parse the CMML preamble */
380 gst_cmml_enc_parse_preamble (GstCmmlEnc * enc,
381 guchar * preamble, guchar * processing_instruction)
383 GST_INFO_OBJECT (enc, "parsing preamble");
385 /* save the preamble: it will be pushed when the head tag is found */
386 enc->preamble = (guchar *) g_strconcat ((gchar *) preamble,
387 (gchar *) processing_instruction, NULL);
390 /* parse the CMML end tag */
392 gst_cmml_enc_parse_end_tag (GstCmmlEnc * enc)
396 GST_INFO_OBJECT (enc, "parsing end tag");
398 /* push an empty buffer to signal EOS */
399 enc->flow_return = gst_cmml_enc_new_buffer (enc, NULL, 0, &buffer);
400 if (enc->flow_return == GST_FLOW_OK) {
401 /* set granulepos 0 on EOS */
402 GST_BUFFER_OFFSET_END (buffer) = 0;
403 enc->flow_return = gst_cmml_enc_push (enc, buffer);
404 enc->sent_eos = TRUE;
410 /* encode the CMML head tag and push the CMML headers
413 gst_cmml_enc_parse_tag_head (GstCmmlEnc * enc, GstCmmlTagHead * head)
415 GList *headers = NULL;
419 GstBuffer *ident_buf, *preamble_buf, *head_buf;
422 if (enc->preamble == NULL)
423 goto flow_unexpected;
425 GST_INFO_OBJECT (enc, "parsing head tag");
427 enc->flow_return = gst_cmml_enc_new_ident_header (enc, &ident_buf);
428 if (enc->flow_return != GST_FLOW_OK)
430 headers = g_list_append (headers, ident_buf);
432 enc->flow_return = gst_cmml_enc_new_buffer (enc,
433 enc->preamble, strlen ((gchar *) enc->preamble), &preamble_buf);
434 if (enc->flow_return != GST_FLOW_OK)
436 headers = g_list_append (headers, preamble_buf);
438 head_string = gst_cmml_parser_tag_head_to_string (enc->parser, head);
439 enc->flow_return = gst_cmml_enc_new_buffer (enc,
440 head_string, strlen ((gchar *) head_string), &head_buf);
441 g_free (head_string);
442 if (enc->flow_return != GST_FLOW_OK)
444 headers = g_list_append (headers, head_buf);
446 caps = gst_pad_get_caps (enc->srcpad);
447 caps = gst_cmml_enc_set_header_on_caps (enc, caps,
448 ident_buf, preamble_buf, head_buf);
451 buffer = GST_BUFFER (headers->data);
452 /* set granulepos 0 on headers */
453 GST_BUFFER_OFFSET_END (buffer) = 0;
454 gst_buffer_set_caps (buffer, caps);
456 enc->flow_return = gst_cmml_enc_push (enc, buffer);
457 headers = g_list_delete_link (headers, headers);
459 if (enc->flow_return != GST_FLOW_OK)
463 gst_caps_unref (caps);
465 enc->sent_headers = TRUE;
469 GST_ELEMENT_ERROR (enc, STREAM, ENCODE,
470 (NULL), ("got head tag before preamble"));
471 enc->flow_return = GST_FLOW_ERROR;
474 gst_caps_unref (caps);
477 for (walk = headers; walk; walk = walk->next)
478 gst_buffer_unref (GST_BUFFER (walk->data));
479 g_list_free (headers);
483 /* encode a CMML clip tag
484 * remove the start and end attributes (GstCmmlParser does this itself) and
485 * push the tag with the timestamp of its start attribute. If the tag has the
486 * end attribute, create a new empty clip and encode it.
489 gst_cmml_enc_parse_tag_clip (GstCmmlEnc * enc, GstCmmlTagClip * clip)
491 GstCmmlTagClip *prev_clip;
492 GstClockTime prev_clip_time = GST_CLOCK_TIME_NONE;
494 /* this can happen if there's a programming error (eg user forgets to set
495 * the start-time property) or if one of the gst_cmml_clock_time_from_*
496 * overflows in GstCmmlParser */
497 if (clip->start_time == GST_CLOCK_TIME_NONE) {
498 GST_ELEMENT_ERROR (enc, STREAM, ENCODE,
499 (NULL), ("invalid start time for clip (%s)", clip->id));
500 enc->flow_return = GST_FLOW_ERROR;
505 /* get the previous clip's start time to encode the current granulepos */
506 prev_clip = gst_cmml_track_list_get_track_last_clip (enc->tracks,
507 (gchar *) clip->track);
509 prev_clip_time = prev_clip->start_time;
510 if (prev_clip_time > clip->start_time) {
511 GST_ELEMENT_ERROR (enc, STREAM, ENCODE,
512 (NULL), ("previous clip start time > current clip (%s) start time",
514 enc->flow_return = GST_FLOW_ERROR;
518 /* we don't need the prev clip anymore */
519 gst_cmml_track_list_del_clip (enc->tracks, prev_clip);
522 /* add the current clip to the tracklist */
523 gst_cmml_track_list_add_clip (enc->tracks, clip);
525 enc->flow_return = gst_cmml_enc_push_clip (enc, clip, prev_clip_time);
529 gst_cmml_enc_push_clip (GstCmmlEnc * enc, GstCmmlTagClip * clip,
530 GstClockTime prev_clip_time)
537 /* encode the clip */
539 (gchar *) gst_cmml_parser_tag_clip_to_string (enc->parser, clip);
541 res = gst_cmml_enc_new_buffer (enc,
542 (guchar *) clip_string, strlen (clip_string), &buffer);
543 g_free (clip_string);
544 if (res != GST_FLOW_OK)
547 GST_INFO_OBJECT (enc, "encoding clip"
548 "(start-time: %" GST_TIME_FORMAT " end-time: %" GST_TIME_FORMAT,
549 GST_TIME_ARGS (clip->start_time), GST_TIME_ARGS (clip->end_time));
551 /* set the granulepos */
552 granulepos = gst_cmml_clock_time_to_granule (prev_clip_time, clip->start_time,
553 enc->granulerate_n, enc->granulerate_d, enc->granuleshift);
554 if (granulepos == -1) {
555 gst_buffer_unref (buffer);
556 goto granule_overflow;
559 GST_BUFFER_OFFSET (buffer) = clip->start_time;
560 GST_BUFFER_OFFSET_END (buffer) = granulepos;
561 GST_BUFFER_TIMESTAMP (buffer) = clip->start_time;
563 res = gst_cmml_enc_push (enc, buffer);
564 if (res != GST_FLOW_OK)
567 if (clip->end_time != GST_CLOCK_TIME_NONE) {
568 /* create a new empty clip for the same cmml track starting at end_time
570 GObject *end_clip = g_object_new (GST_TYPE_CMML_TAG_CLIP,
571 "start-time", clip->end_time, "track", clip->track, NULL);
573 /* encode the empty end clip */
574 gst_cmml_enc_push_clip (enc, GST_CMML_TAG_CLIP (end_clip),
576 g_object_unref (end_clip);
582 GST_ELEMENT_ERROR (enc, STREAM, ENCODE, (NULL), ("granulepos overflow"));
583 return GST_FLOW_ERROR;
587 gst_cmml_enc_push (GstCmmlEnc * enc, GstBuffer * buffer)
591 res = gst_pad_push (enc->srcpad, buffer);
592 if (res != GST_FLOW_OK)
593 GST_WARNING_OBJECT (enc, "push returned: %s", gst_flow_get_name (res));
599 gst_cmml_enc_chain (GstPad * pad, GstBuffer * buffer)
602 GstCmmlEnc *enc = GST_CMML_ENC (GST_PAD_PARENT (pad));
604 /* the CMML handlers registered with enc->parser will override this when
605 * encoding/pushing the buffers downstream
607 enc->flow_return = GST_FLOW_OK;
609 if (!gst_cmml_parser_parse_chunk (enc->parser,
610 (gchar *) GST_BUFFER_DATA (buffer), GST_BUFFER_SIZE (buffer), &err)) {
611 GST_ELEMENT_ERROR (enc, STREAM, ENCODE, (NULL), ("%s", err->message));
613 enc->flow_return = GST_FLOW_ERROR;
616 gst_buffer_unref (buffer);
617 return enc->flow_return;
621 gst_cmml_enc_plugin_init (GstPlugin * plugin)
623 if (!gst_element_register (plugin, "cmmlenc", GST_RANK_NONE,
627 GST_DEBUG_CATEGORY_INIT (cmmlenc, "cmmlenc", 0,
628 "annodex cmml decoding element");