2 * Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>
4 * gsttaglist.c: tag support (aka metadata)
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
24 * @short_description: List of tags and values used to describe media metadata
26 * List of tags and values used to describe media metadata.
28 * Strings must be in ASCII or UTF-8 encoding. No other encodings are allowed.
30 * Last reviewed on 2009-06-09 (0.10.23)
37 #include "gst_private.h"
38 #include "math-compat.h"
39 #include "gst-i18n-lib.h"
40 #include "gsttaglist.h"
43 #include "gstbuffer.h"
45 #include "gststructure.h"
47 #include <gobject/gvaluecollector.h>
50 #define GST_TAG_IS_VALID(tag) (gst_tag_get_info (tag) != NULL)
52 /* FIXME 0.11: make taglists refcounted maybe? */
53 /* a tag list is basically a structure, but we don't make this fact public */
57 GstStructure *structure;
60 /* FIXME 0.11: use GParamSpecs or something similar for tag registrations,
61 * possibly even gst_tag_register(). Especially value ranges might be
62 * useful for some tags. */
66 GType type; /* type the data is in */
68 gchar *nick; /* translated name */
69 gchar *blurb; /* translated description of type */
71 GstTagMergeFunc merge_func; /* functions to merge the values */
72 GstTagFlag flag; /* type of tag */
73 GQuark name_quark; /* quark for the name */
77 #define g_value_get_char g_value_get_schar
79 static GMutex __tag_mutex;
80 #define TAG_LOCK g_mutex_lock (&__tag_mutex)
81 #define TAG_UNLOCK g_mutex_unlock (&__tag_mutex)
83 /* tags hash table: maps tag name string => GstTagInfo */
84 static GHashTable *__tags;
86 G_DEFINE_BOXED_TYPE (GstTagList, gst_tag_list,
87 (GBoxedCopyFunc) gst_tag_list_copy, (GBoxedFreeFunc) gst_tag_list_free);
90 * g_value_register_transform_func (_gst_tag_list_type, G_TYPE_STRING,
91 * _gst_structure_transform_to_string);
95 _priv_gst_tag_initialize (void)
97 g_mutex_init (&__tag_mutex);
99 __tags = g_hash_table_new (g_str_hash, g_str_equal);
100 gst_tag_register (GST_TAG_TITLE, GST_TAG_FLAG_META,
102 _("title"), _("commonly used title"), gst_tag_merge_strings_with_comma);
103 gst_tag_register (GST_TAG_TITLE_SORTNAME, GST_TAG_FLAG_META,
105 _("title sortname"), _("commonly used title for sorting purposes"), NULL);
106 gst_tag_register (GST_TAG_ARTIST, GST_TAG_FLAG_META,
109 _("person(s) responsible for the recording"),
110 gst_tag_merge_strings_with_comma);
111 gst_tag_register (GST_TAG_ARTIST_SORTNAME, GST_TAG_FLAG_META,
113 _("artist sortname"),
114 _("person(s) responsible for the recording for sorting purposes"), NULL);
115 gst_tag_register (GST_TAG_ALBUM, GST_TAG_FLAG_META,
118 _("album containing this data"), gst_tag_merge_strings_with_comma);
119 gst_tag_register (GST_TAG_ALBUM_SORTNAME, GST_TAG_FLAG_META,
122 _("album containing this data for sorting purposes"), NULL);
123 gst_tag_register (GST_TAG_ALBUM_ARTIST, GST_TAG_FLAG_META,
126 _("The artist of the entire album, as it should be displayed"),
127 gst_tag_merge_strings_with_comma);
128 gst_tag_register (GST_TAG_ALBUM_ARTIST_SORTNAME, GST_TAG_FLAG_META,
130 _("album artist sortname"),
131 _("The artist of the entire album, as it should be sorted"), NULL);
132 gst_tag_register (GST_TAG_DATE, GST_TAG_FLAG_META, G_TYPE_DATE,
133 _("date"), _("date the data was created (as a GDate structure)"), NULL);
134 gst_tag_register (GST_TAG_DATE_TIME, GST_TAG_FLAG_META, GST_TYPE_DATE_TIME,
136 _("date and time the data was created (as a GstDateTime structure)"),
138 gst_tag_register (GST_TAG_GENRE, GST_TAG_FLAG_META,
141 _("genre this data belongs to"), gst_tag_merge_strings_with_comma);
142 gst_tag_register (GST_TAG_COMMENT, GST_TAG_FLAG_META,
145 _("free text commenting the data"), gst_tag_merge_use_first);
146 gst_tag_register (GST_TAG_EXTENDED_COMMENT, GST_TAG_FLAG_META,
148 _("extended comment"),
149 _("free text commenting the data in key=value or key[en]=comment form"),
150 gst_tag_merge_use_first);
151 gst_tag_register (GST_TAG_TRACK_NUMBER, GST_TAG_FLAG_META,
154 _("track number inside a collection"), gst_tag_merge_use_first);
155 gst_tag_register (GST_TAG_TRACK_COUNT, GST_TAG_FLAG_META,
158 _("count of tracks inside collection this track belongs to"),
159 gst_tag_merge_use_first);
160 gst_tag_register (GST_TAG_ALBUM_VOLUME_NUMBER, GST_TAG_FLAG_META,
163 _("disc number inside a collection"), gst_tag_merge_use_first);
164 gst_tag_register (GST_TAG_ALBUM_VOLUME_COUNT, GST_TAG_FLAG_META,
167 _("count of discs inside collection this disc belongs to"),
168 gst_tag_merge_use_first);
169 gst_tag_register (GST_TAG_LOCATION, GST_TAG_FLAG_META,
171 _("location"), _("Origin of media as a URI (location, where the "
172 "original of the file or stream is hosted)"),
173 gst_tag_merge_strings_with_comma);
174 gst_tag_register (GST_TAG_HOMEPAGE, GST_TAG_FLAG_META,
177 _("Homepage for this media (i.e. artist or movie homepage)"),
178 gst_tag_merge_strings_with_comma);
179 gst_tag_register (GST_TAG_DESCRIPTION, GST_TAG_FLAG_META, G_TYPE_STRING,
180 _("description"), _("short text describing the content of the data"),
181 gst_tag_merge_strings_with_comma);
182 gst_tag_register (GST_TAG_VERSION, GST_TAG_FLAG_META, G_TYPE_STRING,
183 _("version"), _("version of this data"), NULL);
184 gst_tag_register (GST_TAG_ISRC, GST_TAG_FLAG_META, G_TYPE_STRING, _("ISRC"),
186 ("International Standard Recording Code - see http://www.ifpi.org/isrc/"),
188 /* FIXME: organization (fix what? tpm) */
189 gst_tag_register (GST_TAG_ORGANIZATION, GST_TAG_FLAG_META, G_TYPE_STRING,
190 _("organization"), _("organization"), gst_tag_merge_strings_with_comma);
191 gst_tag_register (GST_TAG_COPYRIGHT, GST_TAG_FLAG_META,
192 G_TYPE_STRING, _("copyright"), _("copyright notice of the data"), NULL);
193 gst_tag_register (GST_TAG_COPYRIGHT_URI, GST_TAG_FLAG_META,
194 G_TYPE_STRING, _("copyright uri"),
195 _("URI to the copyright notice of the data"), NULL);
196 gst_tag_register (GST_TAG_ENCODED_BY, GST_TAG_FLAG_META, G_TYPE_STRING,
197 _("encoded by"), _("name of the encoding person or organization"),
198 gst_tag_merge_strings_with_comma);
199 gst_tag_register (GST_TAG_CONTACT, GST_TAG_FLAG_META,
201 _("contact"), _("contact information"), gst_tag_merge_strings_with_comma);
202 gst_tag_register (GST_TAG_LICENSE, GST_TAG_FLAG_META,
203 G_TYPE_STRING, _("license"), _("license of data"), NULL);
204 gst_tag_register (GST_TAG_LICENSE_URI, GST_TAG_FLAG_META,
205 G_TYPE_STRING, _("license uri"),
206 _("URI to the license of the data"), NULL);
207 gst_tag_register (GST_TAG_PERFORMER, GST_TAG_FLAG_META,
210 _("person(s) performing"), gst_tag_merge_strings_with_comma);
211 gst_tag_register (GST_TAG_COMPOSER, GST_TAG_FLAG_META,
214 _("person(s) who composed the recording"),
215 gst_tag_merge_strings_with_comma);
216 gst_tag_register (GST_TAG_DURATION, GST_TAG_FLAG_DECODED,
218 _("duration"), _("length in GStreamer time units (nanoseconds)"), NULL);
219 gst_tag_register (GST_TAG_CODEC, GST_TAG_FLAG_ENCODED,
222 _("codec the data is stored in"), gst_tag_merge_strings_with_comma);
223 gst_tag_register (GST_TAG_VIDEO_CODEC, GST_TAG_FLAG_ENCODED,
225 _("video codec"), _("codec the video data is stored in"), NULL);
226 gst_tag_register (GST_TAG_AUDIO_CODEC, GST_TAG_FLAG_ENCODED,
228 _("audio codec"), _("codec the audio data is stored in"), NULL);
229 gst_tag_register (GST_TAG_SUBTITLE_CODEC, GST_TAG_FLAG_ENCODED,
231 _("subtitle codec"), _("codec the subtitle data is stored in"), NULL);
232 gst_tag_register (GST_TAG_CONTAINER_FORMAT, GST_TAG_FLAG_ENCODED,
233 G_TYPE_STRING, _("container format"),
234 _("container format the data is stored in"), NULL);
235 gst_tag_register (GST_TAG_BITRATE, GST_TAG_FLAG_ENCODED,
236 G_TYPE_UINT, _("bitrate"), _("exact or average bitrate in bits/s"), NULL);
237 gst_tag_register (GST_TAG_NOMINAL_BITRATE, GST_TAG_FLAG_ENCODED,
238 G_TYPE_UINT, _("nominal bitrate"), _("nominal bitrate in bits/s"), NULL);
239 gst_tag_register (GST_TAG_MINIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
240 G_TYPE_UINT, _("minimum bitrate"), _("minimum bitrate in bits/s"), NULL);
241 gst_tag_register (GST_TAG_MAXIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
242 G_TYPE_UINT, _("maximum bitrate"), _("maximum bitrate in bits/s"), NULL);
243 gst_tag_register (GST_TAG_ENCODER, GST_TAG_FLAG_ENCODED,
245 _("encoder"), _("encoder used to encode this stream"), NULL);
246 gst_tag_register (GST_TAG_ENCODER_VERSION, GST_TAG_FLAG_ENCODED,
248 _("encoder version"),
249 _("version of the encoder used to encode this stream"), NULL);
250 gst_tag_register (GST_TAG_SERIAL, GST_TAG_FLAG_ENCODED,
251 G_TYPE_UINT, _("serial"), _("serial number of track"), NULL);
252 gst_tag_register (GST_TAG_TRACK_GAIN, GST_TAG_FLAG_META,
253 G_TYPE_DOUBLE, _("replaygain track gain"), _("track gain in db"), NULL);
254 gst_tag_register (GST_TAG_TRACK_PEAK, GST_TAG_FLAG_META,
255 G_TYPE_DOUBLE, _("replaygain track peak"), _("peak of the track"), NULL);
256 gst_tag_register (GST_TAG_ALBUM_GAIN, GST_TAG_FLAG_META,
257 G_TYPE_DOUBLE, _("replaygain album gain"), _("album gain in db"), NULL);
258 gst_tag_register (GST_TAG_ALBUM_PEAK, GST_TAG_FLAG_META,
259 G_TYPE_DOUBLE, _("replaygain album peak"), _("peak of the album"), NULL);
260 gst_tag_register (GST_TAG_REFERENCE_LEVEL, GST_TAG_FLAG_META,
261 G_TYPE_DOUBLE, _("replaygain reference level"),
262 _("reference level of track and album gain values"), NULL);
263 gst_tag_register (GST_TAG_LANGUAGE_CODE, GST_TAG_FLAG_META, G_TYPE_STRING,
265 _("language code for this stream, conforming to ISO-639-1 or ISO-639-2"),
267 gst_tag_register (GST_TAG_LANGUAGE_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
269 _("freeform name of the language this stream is in"), NULL);
270 gst_tag_register (GST_TAG_IMAGE, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
271 _("image"), _("image related to this stream"), gst_tag_merge_use_first);
272 gst_tag_register (GST_TAG_PREVIEW_IMAGE, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
273 /* TRANSLATORS: 'preview image' = image that shows a preview of the full image */
274 _("preview image"), _("preview image related to this stream"), NULL);
275 gst_tag_register (GST_TAG_ATTACHMENT, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
276 _("attachment"), _("file attached to this stream"),
277 gst_tag_merge_use_first);
278 gst_tag_register (GST_TAG_BEATS_PER_MINUTE, GST_TAG_FLAG_META, G_TYPE_DOUBLE,
279 _("beats per minute"), _("number of beats per minute in audio"), NULL);
280 gst_tag_register (GST_TAG_KEYWORDS, GST_TAG_FLAG_META, G_TYPE_STRING,
281 _("keywords"), _("comma separated keywords describing the content"),
282 gst_tag_merge_strings_with_comma);
283 gst_tag_register (GST_TAG_GEO_LOCATION_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
284 _("geo location name"), _("human readable descriptive location of where "
285 "the media has been recorded or produced"), NULL);
286 gst_tag_register (GST_TAG_GEO_LOCATION_LATITUDE, GST_TAG_FLAG_META,
287 G_TYPE_DOUBLE, _("geo location latitude"),
288 _("geo latitude location of where the media has been recorded or "
289 "produced in degrees according to WGS84 (zero at the equator, "
290 "negative values for southern latitudes)"), NULL);
291 gst_tag_register (GST_TAG_GEO_LOCATION_LONGITUDE, GST_TAG_FLAG_META,
292 G_TYPE_DOUBLE, _("geo location longitude"),
293 _("geo longitude location of where the media has been recorded or "
294 "produced in degrees according to WGS84 (zero at the prime meridian "
295 "in Greenwich/UK, negative values for western longitudes)"), NULL);
296 gst_tag_register (GST_TAG_GEO_LOCATION_ELEVATION, GST_TAG_FLAG_META,
297 G_TYPE_DOUBLE, _("geo location elevation"),
298 _("geo elevation of where the media has been recorded or produced in "
299 "meters according to WGS84 (zero is average sea level)"), NULL);
300 gst_tag_register (GST_TAG_GEO_LOCATION_COUNTRY, GST_TAG_FLAG_META,
301 G_TYPE_STRING, _("geo location country"),
302 _("country (english name) where the media has been recorded "
303 "or produced"), NULL);
304 gst_tag_register (GST_TAG_GEO_LOCATION_CITY, GST_TAG_FLAG_META,
305 G_TYPE_STRING, _("geo location city"),
306 _("city (english name) where the media has been recorded "
307 "or produced"), NULL);
308 gst_tag_register (GST_TAG_GEO_LOCATION_SUBLOCATION, GST_TAG_FLAG_META,
309 G_TYPE_STRING, _("geo location sublocation"),
310 _("a location whithin a city where the media has been produced "
311 "or created (e.g. the neighborhood)"), NULL);
312 gst_tag_register (GST_TAG_GEO_LOCATION_HORIZONTAL_ERROR, GST_TAG_FLAG_META,
313 G_TYPE_DOUBLE, _("geo location horizontal error"),
314 _("expected error of the horizontal positioning measures (in meters)"),
316 gst_tag_register (GST_TAG_GEO_LOCATION_MOVEMENT_SPEED, GST_TAG_FLAG_META,
317 G_TYPE_DOUBLE, _("geo location movement speed"),
318 _("movement speed of the capturing device while performing the capture "
320 gst_tag_register (GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION, GST_TAG_FLAG_META,
321 G_TYPE_DOUBLE, _("geo location movement direction"),
322 _("indicates the movement direction of the device performing the capture"
323 " of a media. It is represented as degrees in floating point "
324 "representation, 0 means the geographic north, and increases "
326 gst_tag_register (GST_TAG_GEO_LOCATION_CAPTURE_DIRECTION, GST_TAG_FLAG_META,
327 G_TYPE_DOUBLE, _("geo location capture direction"),
328 _("indicates the direction the device is pointing to when capturing "
329 " a media. It is represented as degrees in floating point "
330 " representation, 0 means the geographic north, and increases "
332 gst_tag_register (GST_TAG_SHOW_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
333 /* TRANSLATORS: 'show name' = 'TV/radio/podcast show name' here */
335 _("Name of the tv/podcast/series show the media is from"),
336 gst_tag_merge_strings_with_comma);
337 gst_tag_register (GST_TAG_SHOW_SORTNAME, GST_TAG_FLAG_META, G_TYPE_STRING,
338 /* TRANSLATORS: 'show sortname' = 'TV/radio/podcast show name as used for sorting purposes' here */
340 _("Name of the tv/podcast/series show the media is from, for sorting "
342 gst_tag_register (GST_TAG_SHOW_EPISODE_NUMBER, GST_TAG_FLAG_META, G_TYPE_UINT,
344 _("The episode number in the season the media is part of"),
345 gst_tag_merge_use_first);
346 gst_tag_register (GST_TAG_SHOW_SEASON_NUMBER, GST_TAG_FLAG_META, G_TYPE_UINT,
348 _("The season number of the show the media is part of"),
349 gst_tag_merge_use_first);
350 gst_tag_register (GST_TAG_LYRICS, GST_TAG_FLAG_META, G_TYPE_STRING,
351 _("lyrics"), _("The lyrics of the media, commonly used for songs"),
352 gst_tag_merge_strings_with_comma);
353 gst_tag_register (GST_TAG_COMPOSER_SORTNAME, GST_TAG_FLAG_META, G_TYPE_STRING,
354 _("composer sortname"),
355 _("person(s) who composed the recording, for sorting purposes"), NULL);
356 gst_tag_register (GST_TAG_GROUPING, GST_TAG_FLAG_META, G_TYPE_STRING,
358 _("Groups related media that spans multiple tracks, like the different "
359 "pieces of a concerto. It is a higher level than a track, "
360 "but lower than an album"), NULL);
361 gst_tag_register (GST_TAG_USER_RATING, GST_TAG_FLAG_META, G_TYPE_UINT,
363 _("Rating attributed by a user. The higher the rank, "
364 "the more the user likes this media"), NULL);
365 gst_tag_register (GST_TAG_DEVICE_MANUFACTURER, GST_TAG_FLAG_META,
366 G_TYPE_STRING, _("device manufacturer"),
367 _("Manufacturer of the device used to create this media"), NULL);
368 gst_tag_register (GST_TAG_DEVICE_MODEL, GST_TAG_FLAG_META, G_TYPE_STRING,
370 _("Model of the device used to create this media"), NULL);
371 gst_tag_register (GST_TAG_APPLICATION_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
372 _("application name"), _("Application used to create the media"), NULL);
373 gst_tag_register (GST_TAG_APPLICATION_DATA, GST_TAG_FLAG_META,
374 GST_TYPE_BUFFER, _("application data"),
375 _("Arbitrary application data to be serialized into the media"), NULL);
376 gst_tag_register (GST_TAG_IMAGE_ORIENTATION, GST_TAG_FLAG_META, G_TYPE_STRING,
377 _("image orientation"),
378 _("How the image should be rotated or flipped before display"), NULL);
382 * gst_tag_merge_use_first:
383 * @dest: (out caller-allocates): uninitialized GValue to store result in
384 * @src: GValue to copy from
386 * This is a convenience function for the func argument of gst_tag_register().
387 * It creates a copy of the first value from the list.
390 gst_tag_merge_use_first (GValue * dest, const GValue * src)
392 const GValue *ret = gst_value_list_get_value (src, 0);
394 g_value_init (dest, G_VALUE_TYPE (ret));
395 g_value_copy (ret, dest);
399 * gst_tag_merge_strings_with_comma:
400 * @dest: (out caller-allocates): uninitialized GValue to store result in
401 * @src: GValue to copy from
403 * This is a convenience function for the func argument of gst_tag_register().
404 * It concatenates all given strings using a comma. The tag must be registered
405 * as a G_TYPE_STRING or this function will fail.
408 gst_tag_merge_strings_with_comma (GValue * dest, const GValue * src)
413 count = gst_value_list_get_size (src);
414 str = g_string_new (g_value_get_string (gst_value_list_get_value (src, 0)));
415 for (i = 1; i < count; i++) {
416 /* separator between two strings */
417 g_string_append (str, _(", "));
418 g_string_append (str,
419 g_value_get_string (gst_value_list_get_value (src, i)));
422 g_value_init (dest, G_TYPE_STRING);
423 g_value_take_string (dest, str->str);
424 g_string_free (str, FALSE);
428 gst_tag_lookup (const gchar * tag_name)
433 ret = g_hash_table_lookup (__tags, (gpointer) tag_name);
441 * @name: the name or identifier string
442 * @flag: a flag describing the type of tag info
443 * @type: the type this data is in
444 * @nick: human-readable name
445 * @blurb: a human-readable description about this tag
446 * @func: function for merging multiple values of this tag, or NULL
448 * Registers a new tag type for the use with GStreamer's type system. If a type
449 * with that name is already registered, that one is used.
450 * The old registration may have used a different type however. So don't rely
451 * on your supplied values.
453 * Important: if you do not supply a merge function the implication will be
454 * that there can only be one single value for this tag in a tag list and
455 * any additional values will silenty be discarded when being added (unless
456 * #GST_TAG_MERGE_REPLACE, #GST_TAG_MERGE_REPLACE_ALL, or
457 * #GST_TAG_MERGE_PREPEND is used as merge mode, in which case the new
458 * value will replace the old one in the list).
460 * The merge function will be called from gst_tag_list_copy_value() when
461 * it is required that one or more values for a tag be condensed into
462 * one single value. This may happen from gst_tag_list_get_string(),
463 * gst_tag_list_get_int(), gst_tag_list_get_double() etc. What will happen
464 * exactly in that case depends on how the tag was registered and if a
465 * merge function was supplied and if so which one.
467 * Two default merge functions are provided: gst_tag_merge_use_first() and
468 * gst_tag_merge_strings_with_comma().
471 gst_tag_register (const gchar * name, GstTagFlag flag, GType type,
472 const gchar * nick, const gchar * blurb, GstTagMergeFunc func)
477 g_return_if_fail (name != NULL);
478 g_return_if_fail (nick != NULL);
479 g_return_if_fail (blurb != NULL);
480 g_return_if_fail (type != 0 && type != GST_TYPE_LIST);
482 info = gst_tag_lookup (name);
485 g_return_if_fail (info->type == type);
489 info = g_slice_new (GstTagInfo);
492 info->nick = g_strdup (nick);
493 info->blurb = g_strdup (blurb);
494 info->merge_func = func;
496 /* we make a copy for the hash table anyway, which will stay around, so
497 * can use that for the quark table too */
498 name_dup = g_strdup (name);
499 info->name_quark = g_quark_from_static_string (name_dup);
502 g_hash_table_insert (__tags, (gpointer) name_dup, info);
508 * @tag: name of the tag
510 * Checks if the given type is already registered.
512 * Returns: TRUE if the type is already registered
515 gst_tag_exists (const gchar * tag)
517 g_return_val_if_fail (tag != NULL, FALSE);
519 return gst_tag_lookup (tag) != NULL;
526 * Gets the #GType used for this tag.
528 * Returns: the #GType of this tag
531 gst_tag_get_type (const gchar * tag)
535 g_return_val_if_fail (tag != NULL, 0);
536 info = gst_tag_lookup (tag);
537 g_return_val_if_fail (info != NULL, 0);
546 * Returns the human-readable name of this tag, You must not change or free
549 * Returns: the human-readable name of this tag
552 gst_tag_get_nick (const gchar * tag)
556 g_return_val_if_fail (tag != NULL, NULL);
557 info = gst_tag_lookup (tag);
558 g_return_val_if_fail (info != NULL, NULL);
564 * gst_tag_get_description:
567 * Returns the human-readable description of this tag, You must not change or
570 * Returns: the human-readable description of this tag
573 gst_tag_get_description (const gchar * tag)
577 g_return_val_if_fail (tag != NULL, NULL);
578 info = gst_tag_lookup (tag);
579 g_return_val_if_fail (info != NULL, NULL);
588 * Gets the flag of @tag.
590 * Returns: the flag of this tag.
593 gst_tag_get_flag (const gchar * tag)
597 g_return_val_if_fail (tag != NULL, GST_TAG_FLAG_UNDEFINED);
598 info = gst_tag_lookup (tag);
599 g_return_val_if_fail (info != NULL, GST_TAG_FLAG_UNDEFINED);
608 * Checks if the given tag is fixed. A fixed tag can only contain one value.
609 * Unfixed tags can contain lists of values.
611 * Returns: TRUE, if the given tag is fixed.
614 gst_tag_is_fixed (const gchar * tag)
618 g_return_val_if_fail (tag != NULL, FALSE);
619 info = gst_tag_lookup (tag);
620 g_return_val_if_fail (info != NULL, FALSE);
622 return info->merge_func == NULL;
625 /* takes ownership of the structure */
627 gst_tag_list_new_internal (GstStructure * s)
629 GstTagList *tag_list;
631 g_assert (s != NULL);
633 tag_list = g_slice_new0 (GstTagList);
634 tag_list->type = GST_TYPE_TAG_LIST;
635 tag_list->structure = s;
640 * gst_tag_list_new_empty:
642 * Creates a new empty GstTagList.
644 * Free-function: gst_tag_list_free
646 * Returns: (transfer full): An empty tag list
649 gst_tag_list_new_empty (void)
652 GstTagList *tag_list;
654 s = gst_structure_new_id_empty (GST_QUARK (TAGLIST));
655 tag_list = gst_tag_list_new_internal (s);
662 * @...: NULL-terminated list of values to set
664 * Creates a new taglist and appends the values for the given tags. It expects
665 * tag-value pairs like gst_tag_list_add(), and a NULL terminator after the
666 * last pair. The type of the values is implicit and is documented in the API
667 * reference, but can also be queried at runtime with gst_tag_get_type(). It
668 * is an error to pass a value of a type not matching the tag type into this
669 * function. The tag list will make copies of any arguments passed
670 * (e.g. strings, buffers).
672 * Free-function: gst_tag_list_free
674 * Returns: (transfer full): a new #GstTagList. Free with gst_tag_list_free()
675 * when no longer needed.
680 gst_tag_list_new (const gchar * tag, ...)
685 g_return_val_if_fail (tag != NULL, NULL);
687 list = gst_tag_list_new_empty ();
688 va_start (args, tag);
689 gst_tag_list_add_valist (list, GST_TAG_MERGE_APPEND, tag, args);
696 * gst_tag_list_new_valist:
697 * @var_args: tag / value pairs to set
699 * Just like gst_tag_list_new(), only that it takes a va_list argument.
700 * Useful mostly for language bindings.
702 * Free-function: gst_tag_list_free
704 * Returns: (transfer full): a new #GstTagList. Free with gst_tag_list_free()
705 * when no longer needed.
710 gst_tag_list_new_valist (va_list var_args)
715 list = gst_tag_list_new_empty ();
717 tag = va_arg (var_args, gchar *);
718 gst_tag_list_add_valist (list, GST_TAG_MERGE_APPEND, tag, var_args);
724 * gst_tag_list_to_string:
725 * @list: a #GstTagList
727 * Serializes a tag list to a string.
729 * Returns: a newly-allocated string, or NULL in case of an error. The
730 * string must be freed with g_free() when no longer needed.
735 gst_tag_list_to_string (const GstTagList * list)
737 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
739 return gst_structure_to_string (list->structure);
743 * gst_tag_list_new_from_string:
744 * @str: a string created with gst_tag_list_to_string()
746 * Deserializes a tag list.
748 * Returns: a new #GstTagList, or NULL in case of an error.
753 gst_tag_list_new_from_string (const gchar * str)
755 GstTagList *tag_list;
757 g_return_val_if_fail (str != NULL, NULL);
758 g_return_val_if_fail (g_str_has_prefix (str, "taglist"), NULL);
760 tag_list = gst_tag_list_new_internal (gst_structure_from_string (str, NULL));
765 * gst_tag_list_n_tags:
766 * @list: A #GstTagList.
768 * Get the number of tags in @list.
770 * Returns: The number of tags in @list.
773 gst_tag_list_n_tags (const GstTagList * list)
775 g_return_val_if_fail (list != NULL, 0);
776 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
778 return gst_structure_n_fields (list->structure);
782 * gst_tag_list_nth_tag_name:
783 * @list: A #GstTagList.
786 * Get the name of the tag in @list at @index.
788 * Returns: The name of the tag at @index.
791 gst_tag_list_nth_tag_name (const GstTagList * list, guint index)
793 g_return_val_if_fail (list != NULL, 0);
794 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
796 return gst_structure_nth_field_name (list->structure, index);
800 * gst_tag_list_is_empty:
801 * @list: A #GstTagList.
803 * Checks if the given taglist is empty.
805 * Returns: TRUE if the taglist is empty, otherwise FALSE.
810 gst_tag_list_is_empty (const GstTagList * list)
812 g_return_val_if_fail (list != NULL, FALSE);
813 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
815 return (gst_structure_n_fields (list->structure) == 0);
819 gst_tag_list_fields_equal (const GValue * value1, const GValue * value2)
823 if (gst_value_compare (value1, value2) == GST_VALUE_EQUAL)
826 /* fields not equal: add some tolerance for doubles, otherwise bail out */
827 if (!G_VALUE_HOLDS_DOUBLE (value1) || !G_VALUE_HOLDS_DOUBLE (value2))
830 d1 = g_value_get_double (value1);
831 d2 = g_value_get_double (value2);
833 /* This will only work for 'normal' values and values around 0,
834 * which should be good enough for our purposes here
835 * FIXME: maybe add this to gst_value_compare_double() ? */
836 return (fabs (d1 - d2) < 0.0000001);
840 * gst_tag_list_is_equal:
841 * @list1: a #GstTagList.
842 * @list2: a #GstTagList.
844 * Checks if the two given taglists are equal.
846 * Returns: TRUE if the taglists are equal, otherwise FALSE
851 gst_tag_list_is_equal (const GstTagList * list1, const GstTagList * list2)
853 const GstStructure *s1, *s2;
854 gint num_fields1, num_fields2, i;
856 g_return_val_if_fail (GST_IS_TAG_LIST (list1), FALSE);
857 g_return_val_if_fail (GST_IS_TAG_LIST (list2), FALSE);
859 /* we don't just use gst_structure_is_equal() here so we can add some
860 * tolerance for doubles, though maybe we should just add that to
861 * gst_value_compare_double() as well? */
862 s1 = list1->structure;
863 s2 = list2->structure;
865 num_fields1 = gst_structure_n_fields (s1);
866 num_fields2 = gst_structure_n_fields (s2);
868 if (num_fields1 != num_fields2)
871 for (i = 0; i < num_fields1; i++) {
872 const GValue *value1, *value2;
873 const gchar *tag_name;
875 tag_name = gst_structure_nth_field_name (s1, i);
876 value1 = gst_structure_get_value (s1, tag_name);
877 value2 = gst_structure_get_value (s2, tag_name);
882 if (!gst_tag_list_fields_equal (value1, value2))
891 * @taglist: Object that might be a taglist
893 * Checks if the given pointer is a taglist.
895 * Returns: TRUE, if the given pointer is a taglist
898 gst_is_tag_list (GstTagList * taglist)
900 g_return_val_if_fail (taglist != NULL, FALSE);
902 return taglist->type == GST_TYPE_TAG_LIST;
908 GstTagMergeMode mode;
913 gst_tag_list_add_value_internal (GstTagList * tag_list, GstTagMergeMode mode,
914 const gchar * tag, const GValue * value, GstTagInfo * info)
916 GstStructure *list = tag_list->structure;
917 const GValue *value2;
921 info = gst_tag_lookup (tag);
922 if (G_UNLIKELY (info == NULL)) {
923 g_warning ("unknown tag '%s'", tag);
928 tag_quark = info->name_quark;
931 && (value2 = gst_structure_id_get_value (list, tag_quark)) != NULL) {
932 GValue dest = { 0, };
935 case GST_TAG_MERGE_REPLACE_ALL:
936 case GST_TAG_MERGE_REPLACE:
937 gst_structure_id_set_value (list, tag_quark, value);
939 case GST_TAG_MERGE_PREPEND:
940 gst_value_list_merge (&dest, value, value2);
941 gst_structure_id_set_value (list, tag_quark, &dest);
942 g_value_unset (&dest);
944 case GST_TAG_MERGE_APPEND:
945 gst_value_list_merge (&dest, value2, value);
946 gst_structure_id_set_value (list, tag_quark, &dest);
947 g_value_unset (&dest);
949 case GST_TAG_MERGE_KEEP:
950 case GST_TAG_MERGE_KEEP_ALL:
953 g_assert_not_reached ();
958 case GST_TAG_MERGE_APPEND:
959 case GST_TAG_MERGE_KEEP:
960 if (gst_structure_id_get_value (list, tag_quark) != NULL)
963 case GST_TAG_MERGE_REPLACE_ALL:
964 case GST_TAG_MERGE_REPLACE:
965 case GST_TAG_MERGE_PREPEND:
966 gst_structure_id_set_value (list, tag_quark, value);
968 case GST_TAG_MERGE_KEEP_ALL:
971 g_assert_not_reached ();
978 gst_tag_list_copy_foreach (GQuark tag_quark, const GValue * value,
981 GstTagCopyData *copy = (GstTagCopyData *) user_data;
984 tag = g_quark_to_string (tag_quark);
985 gst_tag_list_add_value_internal (copy->list, copy->mode, tag, value, NULL);
991 * gst_tag_list_insert:
992 * @into: list to merge into
993 * @from: list to merge from
994 * @mode: the mode to use
996 * Inserts the tags of the @from list into the first list using the given mode.
999 gst_tag_list_insert (GstTagList * into, const GstTagList * from,
1000 GstTagMergeMode mode)
1002 GstTagCopyData data;
1004 g_return_if_fail (GST_IS_TAG_LIST (into));
1005 g_return_if_fail (GST_IS_TAG_LIST (from));
1006 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1010 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
1011 gst_structure_remove_all_fields (into->structure);
1013 gst_structure_foreach (from->structure, gst_tag_list_copy_foreach, &data);
1017 * gst_tag_list_copy:
1018 * @list: list to copy
1020 * Copies a given #GstTagList.
1022 * Free-function: gst_tag_list_free
1024 * Returns: (transfer full): copy of the given list
1027 gst_tag_list_copy (const GstTagList * list)
1029 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
1032 return gst_tag_list_new_internal (gst_structure_copy (list->structure));
1036 * gst_tag_list_merge:
1037 * @list1: first list to merge
1038 * @list2: second list to merge
1039 * @mode: the mode to use
1041 * Merges the two given lists into a new list. If one of the lists is NULL, a
1042 * copy of the other is returned. If both lists are NULL, NULL is returned.
1044 * Free-function: gst_tag_list_free
1046 * Returns: (transfer full): the new list
1049 gst_tag_list_merge (const GstTagList * list1, const GstTagList * list2,
1050 GstTagMergeMode mode)
1052 GstTagList *list1_cp;
1053 const GstTagList *list2_cp;
1055 g_return_val_if_fail (list1 == NULL || GST_IS_TAG_LIST (list1), NULL);
1056 g_return_val_if_fail (list2 == NULL || GST_IS_TAG_LIST (list2), NULL);
1057 g_return_val_if_fail (GST_TAG_MODE_IS_VALID (mode), NULL);
1059 /* nothing to merge */
1060 if (!list1 && !list2) {
1064 /* create empty list, we need to do this to correctly handling merge modes */
1065 list1_cp = (list1) ? gst_tag_list_copy (list1) : gst_tag_list_new_empty ();
1066 list2_cp = (list2) ? list2 : gst_tag_list_new_empty ();
1068 gst_tag_list_insert (list1_cp, list2_cp, mode);
1071 gst_tag_list_free ((GstTagList *) list2_cp);
1077 * gst_tag_list_free:
1078 * @list: (in) (transfer full): the list to free
1080 * Frees the given list and all associated values.
1083 gst_tag_list_free (GstTagList * list)
1085 g_return_if_fail (GST_IS_TAG_LIST (list));
1086 gst_structure_free (list->structure);
1087 g_slice_free (GstTagList, list);
1091 * gst_tag_list_get_tag_size:
1093 * @tag: the tag to query
1095 * Checks how many value are stored in this tag list for the given tag.
1097 * Returns: The number of tags stored
1100 gst_tag_list_get_tag_size (const GstTagList * list, const gchar * tag)
1102 const GValue *value;
1104 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
1106 value = gst_structure_get_value (list->structure, tag);
1109 if (G_VALUE_TYPE (value) != GST_TYPE_LIST)
1112 return gst_value_list_get_size (value);
1117 * @list: list to set tags in
1118 * @mode: the mode to use
1120 * @...: NULL-terminated list of values to set
1122 * Sets the values for the given tags using the specified mode.
1125 gst_tag_list_add (GstTagList * list, GstTagMergeMode mode, const gchar * tag,
1130 g_return_if_fail (GST_IS_TAG_LIST (list));
1131 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1132 g_return_if_fail (tag != NULL);
1134 va_start (args, tag);
1135 gst_tag_list_add_valist (list, mode, tag, args);
1140 * gst_tag_list_add_values:
1141 * @list: list to set tags in
1142 * @mode: the mode to use
1144 * @...: GValues to set
1146 * Sets the GValues for the given tags using the specified mode.
1149 gst_tag_list_add_values (GstTagList * list, GstTagMergeMode mode,
1150 const gchar * tag, ...)
1154 g_return_if_fail (GST_IS_TAG_LIST (list));
1155 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1156 g_return_if_fail (tag != NULL);
1158 va_start (args, tag);
1159 gst_tag_list_add_valist_values (list, mode, tag, args);
1164 * gst_tag_list_add_valist:
1165 * @list: list to set tags in
1166 * @mode: the mode to use
1168 * @var_args: tag / value pairs to set
1170 * Sets the values for the given tags using the specified mode.
1173 gst_tag_list_add_valist (GstTagList * list, GstTagMergeMode mode,
1174 const gchar * tag, va_list var_args)
1177 gchar *error = NULL;
1179 g_return_if_fail (GST_IS_TAG_LIST (list));
1180 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1181 g_return_if_fail (tag != NULL);
1183 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
1184 gst_structure_remove_all_fields (list->structure);
1187 while (tag != NULL) {
1188 GValue value = { 0, };
1190 info = gst_tag_lookup (tag);
1191 if (G_UNLIKELY (info == NULL)) {
1192 g_warning ("unknown tag '%s'", tag);
1195 G_VALUE_COLLECT_INIT (&value, info->type, var_args, 0, &error);
1197 g_warning ("%s: %s", G_STRLOC, error);
1199 /* we purposely leak the value here, it might not be
1200 * in a sane state if an error condition occoured
1204 gst_tag_list_add_value_internal (list, mode, tag, &value, info);
1205 g_value_unset (&value);
1206 tag = va_arg (var_args, gchar *);
1211 * gst_tag_list_add_valist_values:
1212 * @list: list to set tags in
1213 * @mode: the mode to use
1215 * @var_args: tag / GValue pairs to set
1217 * Sets the GValues for the given tags using the specified mode.
1220 gst_tag_list_add_valist_values (GstTagList * list, GstTagMergeMode mode,
1221 const gchar * tag, va_list var_args)
1223 g_return_if_fail (GST_IS_TAG_LIST (list));
1224 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1225 g_return_if_fail (tag != NULL);
1227 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
1228 gst_structure_remove_all_fields (list->structure);
1231 while (tag != NULL) {
1234 info = gst_tag_lookup (tag);
1235 if (G_UNLIKELY (info == NULL)) {
1236 g_warning ("unknown tag '%s'", tag);
1239 gst_tag_list_add_value_internal (list, mode, tag, va_arg (var_args,
1241 tag = va_arg (var_args, gchar *);
1246 * gst_tag_list_add_value:
1247 * @list: list to set tags in
1248 * @mode: the mode to use
1250 * @value: GValue for this tag
1252 * Sets the GValue for a given tag using the specified mode.
1257 gst_tag_list_add_value (GstTagList * list, GstTagMergeMode mode,
1258 const gchar * tag, const GValue * value)
1260 g_return_if_fail (GST_IS_TAG_LIST (list));
1261 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1262 g_return_if_fail (tag != NULL);
1264 gst_tag_list_add_value_internal (list, mode, tag, value, NULL);
1268 * gst_tag_list_remove_tag:
1269 * @list: list to remove tag from
1270 * @tag: tag to remove
1272 * Removes the given tag from the taglist.
1275 gst_tag_list_remove_tag (GstTagList * list, const gchar * tag)
1277 g_return_if_fail (GST_IS_TAG_LIST (list));
1278 g_return_if_fail (tag != NULL);
1280 gst_structure_remove_field (list->structure, tag);
1285 GstTagForeachFunc func;
1286 const GstTagList *tag_list;
1292 structure_foreach_wrapper (GQuark field_id, const GValue * value,
1295 TagForeachData *data = (TagForeachData *) user_data;
1297 data->func (data->tag_list, g_quark_to_string (field_id), data->data);
1302 * gst_tag_list_foreach:
1303 * @list: list to iterate over
1304 * @func: (scope call): function to be called for each tag
1305 * @user_data: (closure): user specified data
1307 * Calls the given function for each tag inside the tag list. Note that if there
1308 * is no tag, the function won't be called at all.
1311 gst_tag_list_foreach (const GstTagList * list, GstTagForeachFunc func,
1314 TagForeachData data;
1316 g_return_if_fail (GST_IS_TAG_LIST (list));
1317 g_return_if_fail (func != NULL);
1320 data.tag_list = list;
1321 data.data = user_data;
1322 gst_structure_foreach (list->structure, structure_foreach_wrapper, &data);
1326 * gst_tag_list_get_value_index:
1327 * @list: a #GstTagList
1328 * @tag: tag to read out
1329 * @index: number of entry to read out
1331 * Gets the value that is at the given index for the given tag in the given
1334 * Returns: (transfer none): The GValue for the specified entry or NULL if the
1335 * tag wasn't available or the tag doesn't have as many entries
1338 gst_tag_list_get_value_index (const GstTagList * list, const gchar * tag,
1341 const GValue *value;
1343 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
1344 g_return_val_if_fail (tag != NULL, NULL);
1346 value = gst_structure_get_value (list->structure, tag);
1350 if (GST_VALUE_HOLDS_LIST (value)) {
1351 if (index >= gst_value_list_get_size (value))
1353 return gst_value_list_get_value (value, index);
1362 * gst_tag_list_copy_value:
1363 * @dest: (out caller-allocates): uninitialized #GValue to copy into
1364 * @list: list to get the tag from
1365 * @tag: tag to read out
1367 * Copies the contents for the given tag into the value,
1368 * merging multiple values into one if multiple values are associated
1370 * You must g_value_unset() the value after use.
1372 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1376 gst_tag_list_copy_value (GValue * dest, const GstTagList * list,
1381 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1382 g_return_val_if_fail (tag != NULL, FALSE);
1383 g_return_val_if_fail (dest != NULL, FALSE);
1384 g_return_val_if_fail (G_VALUE_TYPE (dest) == 0, FALSE);
1386 src = gst_structure_get_value (list->structure, tag);
1390 if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
1391 GstTagInfo *info = gst_tag_lookup (tag);
1396 /* must be there or lists aren't allowed */
1397 g_assert (info->merge_func);
1398 info->merge_func (dest, src);
1400 g_value_init (dest, G_VALUE_TYPE (src));
1401 g_value_copy (src, dest);
1406 /* FIXME 0.11: this whole merge function business is overdesigned, and the
1407 * _get_foo() API is misleading as well - how many application developers will
1408 * expect gst_tag_list_get_string (list, GST_TAG_ARTIST, &val) might return a
1409 * string with multiple comma-separated artists? _get_foo() should just be
1410 * a convenience wrapper around _get_foo_index (list, tag, 0, &val),
1411 * supplemented by a special _tag_list_get_string_merged() function if needed
1412 * (unless someone can actually think of real use cases where the merge
1413 * function is not 'use first' for non-strings and merge for strings) */
1415 /***** evil macros to get all the gst_tag_list_get_*() functions right *****/
1417 #define TAG_MERGE_FUNCS(name,type,ret) \
1419 gst_tag_list_get_ ## name (const GstTagList *list, const gchar *tag, \
1422 GValue v = { 0, }; \
1424 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
1425 g_return_val_if_fail (tag != NULL, FALSE); \
1426 g_return_val_if_fail (value != NULL, FALSE); \
1428 if (!gst_tag_list_copy_value (&v, list, tag)) \
1430 *value = COPY_FUNC (g_value_get_ ## name (&v)); \
1431 g_value_unset (&v); \
1436 gst_tag_list_get_ ## name ## _index (const GstTagList *list, \
1438 guint index, type *value) \
1442 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
1443 g_return_val_if_fail (tag != NULL, FALSE); \
1444 g_return_val_if_fail (value != NULL, FALSE); \
1446 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL) \
1448 *value = COPY_FUNC (g_value_get_ ## name (v)); \
1452 #define COPY_FUNC /**/
1454 * gst_tag_list_get_boolean:
1455 * @list: a #GstTagList to get the tag from
1456 * @tag: tag to read out
1457 * @value: (out): location for the result
1459 * Copies the contents for the given tag into the value, merging multiple values
1460 * into one if multiple values are associated with the tag.
1462 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1466 * gst_tag_list_get_boolean_index:
1467 * @list: a #GstTagList to get the tag from
1468 * @tag: tag to read out
1469 * @index: number of entry to read out
1470 * @value: (out): location for the result
1472 * Gets the value that is at the given index for the given tag in the given
1475 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1478 TAG_MERGE_FUNCS (boolean, gboolean, TRUE);
1480 * gst_tag_list_get_int:
1481 * @list: a #GstTagList to get the tag from
1482 * @tag: tag to read out
1483 * @value: (out): location for the result
1485 * Copies the contents for the given tag into the value, merging multiple values
1486 * into one if multiple values are associated with the tag.
1488 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1492 * gst_tag_list_get_int_index:
1493 * @list: a #GstTagList to get the tag from
1494 * @tag: tag to read out
1495 * @index: number of entry to read out
1496 * @value: (out): location for the result
1498 * Gets the value that is at the given index for the given tag in the given
1501 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1504 TAG_MERGE_FUNCS (int, gint, TRUE);
1506 * gst_tag_list_get_uint:
1507 * @list: a #GstTagList to get the tag from
1508 * @tag: tag to read out
1509 * @value: (out): location for the result
1511 * Copies the contents for the given tag into the value, merging multiple values
1512 * into one if multiple values are associated with the tag.
1514 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1518 * gst_tag_list_get_uint_index:
1519 * @list: a #GstTagList to get the tag from
1520 * @tag: tag to read out
1521 * @index: number of entry to read out
1522 * @value: (out): location for the result
1524 * Gets the value that is at the given index for the given tag in the given
1527 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1530 TAG_MERGE_FUNCS (uint, guint, TRUE);
1532 * gst_tag_list_get_int64_index:
1533 * @list: a #GstTagList to get the tag from
1534 * @tag: tag to read out
1535 * @index: number of entry to read out
1536 * @value: (out): location for the result
1538 * Gets the value that is at the given index for the given tag in the given
1541 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1544 TAG_MERGE_FUNCS (int64, gint64, TRUE);
1546 * gst_tag_list_get_uint64:
1547 * @list: a #GstTagList to get the tag from
1548 * @tag: tag to read out
1549 * @value: (out): location for the result
1551 * Copies the contents for the given tag into the value, merging multiple values
1552 * into one if multiple values are associated with the tag.
1554 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1558 * gst_tag_list_get_uint64_index:
1559 * @list: a #GstTagList to get the tag from
1560 * @tag: tag to read out
1561 * @index: number of entry to read out
1562 * @value: (out): location for the result
1564 * Gets the value that is at the given index for the given tag in the given
1567 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1570 TAG_MERGE_FUNCS (uint64, guint64, TRUE);
1572 * gst_tag_list_get_float:
1573 * @list: a #GstTagList to get the tag from
1574 * @tag: tag to read out
1575 * @value: (out): location for the result
1577 * Copies the contents for the given tag into the value, merging multiple values
1578 * into one if multiple values are associated with the tag.
1580 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1584 * gst_tag_list_get_float_index:
1585 * @list: a #GstTagList to get the tag from
1586 * @tag: tag to read out
1587 * @index: number of entry to read out
1588 * @value: (out): location for the result
1590 * Gets the value that is at the given index for the given tag in the given
1593 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1596 TAG_MERGE_FUNCS (float, gfloat, TRUE);
1598 * gst_tag_list_get_double:
1599 * @list: a #GstTagList to get the tag from
1600 * @tag: tag to read out
1601 * @value: (out): location for the result
1603 * Copies the contents for the given tag into the value, merging multiple values
1604 * into one if multiple values are associated with the tag.
1606 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1610 * gst_tag_list_get_double_index:
1611 * @list: a #GstTagList to get the tag from
1612 * @tag: tag to read out
1613 * @index: number of entry to read out
1614 * @value: (out): location for the result
1616 * Gets the value that is at the given index for the given tag in the given
1619 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1622 TAG_MERGE_FUNCS (double, gdouble, TRUE);
1624 * gst_tag_list_get_pointer:
1625 * @list: a #GstTagList to get the tag from
1626 * @tag: tag to read out
1627 * @value: (out) (transfer none): location for the result
1629 * Copies the contents for the given tag into the value, merging multiple values
1630 * into one if multiple values are associated with the tag.
1632 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1636 * gst_tag_list_get_pointer_index:
1637 * @list: a #GstTagList to get the tag from
1638 * @tag: tag to read out
1639 * @index: number of entry to read out
1640 * @value: (out) (transfer none): location for the result
1642 * Gets the value that is at the given index for the given tag in the given
1645 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1648 TAG_MERGE_FUNCS (pointer, gpointer, (*value != NULL));
1650 static inline gchar *
1651 _gst_strdup0 (const gchar * s)
1653 if (s == NULL || *s == '\0')
1656 return g_strdup (s);
1660 #define COPY_FUNC _gst_strdup0
1663 * gst_tag_list_get_string:
1664 * @list: a #GstTagList to get the tag from
1665 * @tag: tag to read out
1666 * @value: (out callee-allocates) (transfer full): location for the result
1668 * Copies the contents for the given tag into the value, possibly merging
1669 * multiple values into one if multiple values are associated with the tag.
1671 * Use gst_tag_list_get_string_index (list, tag, 0, value) if you want
1672 * to retrieve the first string associated with this tag unmodified.
1674 * The resulting string in @value will be in UTF-8 encoding and should be
1675 * freed by the caller using g_free when no longer needed. Since 0.10.24 the
1676 * returned string is also guaranteed to be non-NULL and non-empty.
1678 * Free-function: g_free
1680 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1684 * gst_tag_list_get_string_index:
1685 * @list: a #GstTagList to get the tag from
1686 * @tag: tag to read out
1687 * @index: number of entry to read out
1688 * @value: (out callee-allocates) (transfer full): location for the result
1690 * Gets the value that is at the given index for the given tag in the given
1693 * The resulting string in @value will be in UTF-8 encoding and should be
1694 * freed by the caller using g_free when no longer needed. Since 0.10.24 the
1695 * returned string is also guaranteed to be non-NULL and non-empty.
1697 * Free-function: g_free
1699 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1702 TAG_MERGE_FUNCS (string, gchar *, (*value != NULL));
1705 *FIXME 0.11: Instead of _peek (non-copy) and _get (copy), we could have
1706 * _get (non-copy) and _dup (copy) for strings, seems more
1710 * gst_tag_list_peek_string_index:
1711 * @list: a #GstTagList to get the tag from
1712 * @tag: tag to read out
1713 * @index: number of entry to read out
1714 * @value: (out) (transfer none): location for the result
1716 * Peeks at the value that is at the given index for the given tag in the given
1719 * The resulting string in @value will be in UTF-8 encoding and doesn't need
1720 * to be freed by the caller. The returned string is also guaranteed to
1721 * be non-NULL and non-empty.
1723 * Returns: TRUE, if a value was set, FALSE if the tag didn't exist in the
1727 gst_tag_list_peek_string_index (const GstTagList * list,
1728 const gchar * tag, guint index, const gchar ** value)
1732 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1733 g_return_val_if_fail (tag != NULL, FALSE);
1734 g_return_val_if_fail (value != NULL, FALSE);
1736 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1738 *value = g_value_get_string (v);
1739 return *value != NULL && **value != '\0';
1743 * gst_tag_list_get_date:
1744 * @list: a #GstTagList to get the tag from
1745 * @tag: tag to read out
1746 * @value: (out callee-allocates) (transfer full): address of a GDate pointer
1747 * variable to store the result into
1749 * Copies the first date for the given tag in the taglist into the variable
1750 * pointed to by @value. Free the date with g_date_free() when it is no longer
1753 * Free-function: g_date_free
1755 * Returns: TRUE, if a date was copied, FALSE if the tag didn't exist in the
1756 * given list or if it was #NULL.
1759 gst_tag_list_get_date (const GstTagList * list, const gchar * tag,
1764 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1765 g_return_val_if_fail (tag != NULL, FALSE);
1766 g_return_val_if_fail (value != NULL, FALSE);
1768 if (!gst_tag_list_copy_value (&v, list, tag))
1770 *value = (GDate *) g_value_dup_boxed (&v);
1772 return (*value != NULL);
1776 * gst_tag_list_get_date_index:
1777 * @list: a #GstTagList to get the tag from
1778 * @tag: tag to read out
1779 * @index: number of entry to read out
1780 * @value: (out callee-allocates) (transfer full): location for the result
1782 * Gets the date that is at the given index for the given tag in the given
1783 * list and copies it into the variable pointed to by @value. Free the date
1784 * with g_date_free() when it is no longer needed.
1786 * Free-function: g_date_free
1788 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1789 * given list or if it was #NULL.
1792 gst_tag_list_get_date_index (const GstTagList * list,
1793 const gchar * tag, guint index, GDate ** value)
1797 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1798 g_return_val_if_fail (tag != NULL, FALSE);
1799 g_return_val_if_fail (value != NULL, FALSE);
1801 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1803 *value = (GDate *) g_value_dup_boxed (v);
1804 return (*value != NULL);
1808 * gst_tag_list_get_date_time:
1809 * @list: a #GstTagList to get the tag from
1810 * @tag: tag to read out
1811 * @value: (out callee-allocates) (transfer full): address of a #GstDateTime
1812 * pointer variable to store the result into
1814 * Copies the first datetime for the given tag in the taglist into the variable
1815 * pointed to by @value. Unref the date with gst_date_time_unref() when
1816 * it is no longer needed.
1818 * Free-function: gst_date_time_unref
1820 * Returns: TRUE, if a datetime was copied, FALSE if the tag didn't exist in
1821 * thegiven list or if it was #NULL.
1826 gst_tag_list_get_date_time (const GstTagList * list, const gchar * tag,
1827 GstDateTime ** value)
1831 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1832 g_return_val_if_fail (tag != NULL, FALSE);
1833 g_return_val_if_fail (value != NULL, FALSE);
1835 if (!gst_tag_list_copy_value (&v, list, tag))
1838 g_return_val_if_fail (GST_VALUE_HOLDS_DATE_TIME (&v), FALSE);
1840 *value = (GstDateTime *) g_value_dup_boxed (&v);
1842 return (*value != NULL);
1846 * gst_tag_list_get_date_time_index:
1847 * @list: a #GstTagList to get the tag from
1848 * @tag: tag to read out
1849 * @index: number of entry to read out
1850 * @value: (out callee-allocates) (transfer full): location for the result
1852 * Gets the datetime that is at the given index for the given tag in the given
1853 * list and copies it into the variable pointed to by @value. Unref the datetime
1854 * with gst_date_time_unref() when it is no longer needed.
1856 * Free-function: gst_date_time_unref
1858 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1859 * given list or if it was #NULL.
1864 gst_tag_list_get_date_time_index (const GstTagList * list,
1865 const gchar * tag, guint index, GstDateTime ** value)
1869 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1870 g_return_val_if_fail (tag != NULL, FALSE);
1871 g_return_val_if_fail (value != NULL, FALSE);
1873 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1875 *value = (GstDateTime *) g_value_dup_boxed (v);
1876 return (*value != NULL);
1880 * gst_tag_list_get_buffer:
1881 * @list: a #GstTagList to get the tag from
1882 * @tag: tag to read out
1883 * @value: (out callee-allocates) (transfer full): address of a GstBuffer
1884 * pointer variable to store the result into
1886 * Copies the first buffer for the given tag in the taglist into the variable
1887 * pointed to by @value. Free the buffer with gst_buffer_unref() when it is
1890 * Free-function: gst_buffer_unref
1892 * Returns: TRUE, if a buffer was copied, FALSE if the tag didn't exist in the
1893 * given list or if it was #NULL.
1898 gst_tag_list_get_buffer (const GstTagList * list, const gchar * tag,
1903 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1904 g_return_val_if_fail (tag != NULL, FALSE);
1905 g_return_val_if_fail (value != NULL, FALSE);
1907 if (!gst_tag_list_copy_value (&v, list, tag))
1909 *value = g_value_dup_boxed (&v);
1911 return (*value != NULL);
1915 * gst_tag_list_get_buffer_index:
1916 * @list: a #GstTagList to get the tag from
1917 * @tag: tag to read out
1918 * @index: number of entry to read out
1919 * @value: (out callee-allocates) (transfer full): address of a GstBuffer
1920 * pointer variable to store the result into
1922 * Gets the buffer that is at the given index for the given tag in the given
1923 * list and copies it into the variable pointed to by @value. Free the buffer
1924 * with gst_buffer_unref() when it is no longer needed.
1926 * Free-function: gst_buffer_unref
1928 * Returns: TRUE, if a buffer was copied, FALSE if the tag didn't exist in the
1929 * given list or if it was #NULL.
1934 gst_tag_list_get_buffer_index (const GstTagList * list,
1935 const gchar * tag, guint index, GstBuffer ** value)
1939 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1940 g_return_val_if_fail (tag != NULL, FALSE);
1941 g_return_val_if_fail (value != NULL, FALSE);
1943 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1945 *value = g_value_dup_boxed (v);
1946 return (*value != NULL);