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 */
56 GstStructure structure;
59 /* FIXME 0.11: use GParamSpecs or something similar for tag registrations,
60 * possibly even gst_tag_register(). Especially value ranges might be
61 * useful for some tags. */
65 GType type; /* type the data is in */
67 gchar *nick; /* translated name */
68 gchar *blurb; /* translated description of type */
70 GstTagMergeFunc merge_func; /* functions to merge the values */
71 GstTagFlag flag; /* type of tag */
72 GQuark name_quark; /* quark for the name */
76 #define g_value_get_char g_value_get_schar
78 static GMutex __tag_mutex;
79 #define TAG_LOCK g_mutex_lock (&__tag_mutex)
80 #define TAG_UNLOCK g_mutex_unlock (&__tag_mutex)
82 /* tags hash table: maps tag name string => GstTagInfo */
83 static GHashTable *__tags;
85 G_DEFINE_BOXED_TYPE (GstTagList, gst_tag_list,
86 (GBoxedCopyFunc) gst_tag_list_copy, (GBoxedFreeFunc) gst_tag_list_free);
89 * g_value_register_transform_func (_gst_tag_list_type, G_TYPE_STRING,
90 * _gst_structure_transform_to_string);
94 _priv_gst_tag_initialize (void)
96 g_mutex_init (&__tag_mutex);
98 __tags = g_hash_table_new (g_str_hash, g_str_equal);
99 gst_tag_register (GST_TAG_TITLE, GST_TAG_FLAG_META,
101 _("title"), _("commonly used title"), gst_tag_merge_strings_with_comma);
102 gst_tag_register (GST_TAG_TITLE_SORTNAME, GST_TAG_FLAG_META,
104 _("title sortname"), _("commonly used title for sorting purposes"), NULL);
105 gst_tag_register (GST_TAG_ARTIST, GST_TAG_FLAG_META,
108 _("person(s) responsible for the recording"),
109 gst_tag_merge_strings_with_comma);
110 gst_tag_register (GST_TAG_ARTIST_SORTNAME, GST_TAG_FLAG_META,
112 _("artist sortname"),
113 _("person(s) responsible for the recording for sorting purposes"), NULL);
114 gst_tag_register (GST_TAG_ALBUM, GST_TAG_FLAG_META,
117 _("album containing this data"), gst_tag_merge_strings_with_comma);
118 gst_tag_register (GST_TAG_ALBUM_SORTNAME, GST_TAG_FLAG_META,
121 _("album containing this data for sorting purposes"), NULL);
122 gst_tag_register (GST_TAG_ALBUM_ARTIST, GST_TAG_FLAG_META,
125 _("The artist of the entire album, as it should be displayed"),
126 gst_tag_merge_strings_with_comma);
127 gst_tag_register (GST_TAG_ALBUM_ARTIST_SORTNAME, GST_TAG_FLAG_META,
129 _("album artist sortname"),
130 _("The artist of the entire album, as it should be sorted"), NULL);
131 gst_tag_register (GST_TAG_DATE, GST_TAG_FLAG_META, G_TYPE_DATE,
132 _("date"), _("date the data was created (as a GDate structure)"), NULL);
133 gst_tag_register (GST_TAG_DATE_TIME, GST_TAG_FLAG_META, GST_TYPE_DATE_TIME,
135 _("date and time the data was created (as a GstDateTime structure)"),
137 gst_tag_register (GST_TAG_GENRE, GST_TAG_FLAG_META,
140 _("genre this data belongs to"), gst_tag_merge_strings_with_comma);
141 gst_tag_register (GST_TAG_COMMENT, GST_TAG_FLAG_META,
144 _("free text commenting the data"), gst_tag_merge_use_first);
145 gst_tag_register (GST_TAG_EXTENDED_COMMENT, GST_TAG_FLAG_META,
147 _("extended comment"),
148 _("free text commenting the data in key=value or key[en]=comment form"),
149 gst_tag_merge_use_first);
150 gst_tag_register (GST_TAG_TRACK_NUMBER, GST_TAG_FLAG_META,
153 _("track number inside a collection"), gst_tag_merge_use_first);
154 gst_tag_register (GST_TAG_TRACK_COUNT, GST_TAG_FLAG_META,
157 _("count of tracks inside collection this track belongs to"),
158 gst_tag_merge_use_first);
159 gst_tag_register (GST_TAG_ALBUM_VOLUME_NUMBER, GST_TAG_FLAG_META,
162 _("disc number inside a collection"), gst_tag_merge_use_first);
163 gst_tag_register (GST_TAG_ALBUM_VOLUME_COUNT, GST_TAG_FLAG_META,
166 _("count of discs inside collection this disc belongs to"),
167 gst_tag_merge_use_first);
168 gst_tag_register (GST_TAG_LOCATION, GST_TAG_FLAG_META,
170 _("location"), _("Origin of media as a URI (location, where the "
171 "original of the file or stream is hosted)"),
172 gst_tag_merge_strings_with_comma);
173 gst_tag_register (GST_TAG_HOMEPAGE, GST_TAG_FLAG_META,
176 _("Homepage for this media (i.e. artist or movie homepage)"),
177 gst_tag_merge_strings_with_comma);
178 gst_tag_register (GST_TAG_DESCRIPTION, GST_TAG_FLAG_META, G_TYPE_STRING,
179 _("description"), _("short text describing the content of the data"),
180 gst_tag_merge_strings_with_comma);
181 gst_tag_register (GST_TAG_VERSION, GST_TAG_FLAG_META, G_TYPE_STRING,
182 _("version"), _("version of this data"), NULL);
183 gst_tag_register (GST_TAG_ISRC, GST_TAG_FLAG_META, G_TYPE_STRING, _("ISRC"),
185 ("International Standard Recording Code - see http://www.ifpi.org/isrc/"),
187 /* FIXME: organization (fix what? tpm) */
188 gst_tag_register (GST_TAG_ORGANIZATION, GST_TAG_FLAG_META, G_TYPE_STRING,
189 _("organization"), _("organization"), gst_tag_merge_strings_with_comma);
190 gst_tag_register (GST_TAG_COPYRIGHT, GST_TAG_FLAG_META,
191 G_TYPE_STRING, _("copyright"), _("copyright notice of the data"), NULL);
192 gst_tag_register (GST_TAG_COPYRIGHT_URI, GST_TAG_FLAG_META,
193 G_TYPE_STRING, _("copyright uri"),
194 _("URI to the copyright notice of the data"), NULL);
195 gst_tag_register (GST_TAG_ENCODED_BY, GST_TAG_FLAG_META, G_TYPE_STRING,
196 _("encoded by"), _("name of the encoding person or organization"),
197 gst_tag_merge_strings_with_comma);
198 gst_tag_register (GST_TAG_CONTACT, GST_TAG_FLAG_META,
200 _("contact"), _("contact information"), gst_tag_merge_strings_with_comma);
201 gst_tag_register (GST_TAG_LICENSE, GST_TAG_FLAG_META,
202 G_TYPE_STRING, _("license"), _("license of data"), NULL);
203 gst_tag_register (GST_TAG_LICENSE_URI, GST_TAG_FLAG_META,
204 G_TYPE_STRING, _("license uri"),
205 _("URI to the license of the data"), NULL);
206 gst_tag_register (GST_TAG_PERFORMER, GST_TAG_FLAG_META,
209 _("person(s) performing"), gst_tag_merge_strings_with_comma);
210 gst_tag_register (GST_TAG_COMPOSER, GST_TAG_FLAG_META,
213 _("person(s) who composed the recording"),
214 gst_tag_merge_strings_with_comma);
215 gst_tag_register (GST_TAG_DURATION, GST_TAG_FLAG_DECODED,
217 _("duration"), _("length in GStreamer time units (nanoseconds)"), NULL);
218 gst_tag_register (GST_TAG_CODEC, GST_TAG_FLAG_ENCODED,
221 _("codec the data is stored in"), gst_tag_merge_strings_with_comma);
222 gst_tag_register (GST_TAG_VIDEO_CODEC, GST_TAG_FLAG_ENCODED,
224 _("video codec"), _("codec the video data is stored in"), NULL);
225 gst_tag_register (GST_TAG_AUDIO_CODEC, GST_TAG_FLAG_ENCODED,
227 _("audio codec"), _("codec the audio data is stored in"), NULL);
228 gst_tag_register (GST_TAG_SUBTITLE_CODEC, GST_TAG_FLAG_ENCODED,
230 _("subtitle codec"), _("codec the subtitle data is stored in"), NULL);
231 gst_tag_register (GST_TAG_CONTAINER_FORMAT, GST_TAG_FLAG_ENCODED,
232 G_TYPE_STRING, _("container format"),
233 _("container format the data is stored in"), NULL);
234 gst_tag_register (GST_TAG_BITRATE, GST_TAG_FLAG_ENCODED,
235 G_TYPE_UINT, _("bitrate"), _("exact or average bitrate in bits/s"), NULL);
236 gst_tag_register (GST_TAG_NOMINAL_BITRATE, GST_TAG_FLAG_ENCODED,
237 G_TYPE_UINT, _("nominal bitrate"), _("nominal bitrate in bits/s"), NULL);
238 gst_tag_register (GST_TAG_MINIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
239 G_TYPE_UINT, _("minimum bitrate"), _("minimum bitrate in bits/s"), NULL);
240 gst_tag_register (GST_TAG_MAXIMUM_BITRATE, GST_TAG_FLAG_ENCODED,
241 G_TYPE_UINT, _("maximum bitrate"), _("maximum bitrate in bits/s"), NULL);
242 gst_tag_register (GST_TAG_ENCODER, GST_TAG_FLAG_ENCODED,
244 _("encoder"), _("encoder used to encode this stream"), NULL);
245 gst_tag_register (GST_TAG_ENCODER_VERSION, GST_TAG_FLAG_ENCODED,
247 _("encoder version"),
248 _("version of the encoder used to encode this stream"), NULL);
249 gst_tag_register (GST_TAG_SERIAL, GST_TAG_FLAG_ENCODED,
250 G_TYPE_UINT, _("serial"), _("serial number of track"), NULL);
251 gst_tag_register (GST_TAG_TRACK_GAIN, GST_TAG_FLAG_META,
252 G_TYPE_DOUBLE, _("replaygain track gain"), _("track gain in db"), NULL);
253 gst_tag_register (GST_TAG_TRACK_PEAK, GST_TAG_FLAG_META,
254 G_TYPE_DOUBLE, _("replaygain track peak"), _("peak of the track"), NULL);
255 gst_tag_register (GST_TAG_ALBUM_GAIN, GST_TAG_FLAG_META,
256 G_TYPE_DOUBLE, _("replaygain album gain"), _("album gain in db"), NULL);
257 gst_tag_register (GST_TAG_ALBUM_PEAK, GST_TAG_FLAG_META,
258 G_TYPE_DOUBLE, _("replaygain album peak"), _("peak of the album"), NULL);
259 gst_tag_register (GST_TAG_REFERENCE_LEVEL, GST_TAG_FLAG_META,
260 G_TYPE_DOUBLE, _("replaygain reference level"),
261 _("reference level of track and album gain values"), NULL);
262 gst_tag_register (GST_TAG_LANGUAGE_CODE, GST_TAG_FLAG_META, G_TYPE_STRING,
264 _("language code for this stream, conforming to ISO-639-1 or ISO-639-2"),
266 gst_tag_register (GST_TAG_LANGUAGE_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
268 _("freeform name of the language this stream is in"), NULL);
269 gst_tag_register (GST_TAG_IMAGE, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
270 _("image"), _("image related to this stream"), gst_tag_merge_use_first);
271 gst_tag_register (GST_TAG_PREVIEW_IMAGE, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
272 /* TRANSLATORS: 'preview image' = image that shows a preview of the full image */
273 _("preview image"), _("preview image related to this stream"), NULL);
274 gst_tag_register (GST_TAG_ATTACHMENT, GST_TAG_FLAG_META, GST_TYPE_SAMPLE,
275 _("attachment"), _("file attached to this stream"),
276 gst_tag_merge_use_first);
277 gst_tag_register (GST_TAG_BEATS_PER_MINUTE, GST_TAG_FLAG_META, G_TYPE_DOUBLE,
278 _("beats per minute"), _("number of beats per minute in audio"), NULL);
279 gst_tag_register (GST_TAG_KEYWORDS, GST_TAG_FLAG_META, G_TYPE_STRING,
280 _("keywords"), _("comma separated keywords describing the content"),
281 gst_tag_merge_strings_with_comma);
282 gst_tag_register (GST_TAG_GEO_LOCATION_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
283 _("geo location name"), _("human readable descriptive location of where "
284 "the media has been recorded or produced"), NULL);
285 gst_tag_register (GST_TAG_GEO_LOCATION_LATITUDE, GST_TAG_FLAG_META,
286 G_TYPE_DOUBLE, _("geo location latitude"),
287 _("geo latitude location of where the media has been recorded or "
288 "produced in degrees according to WGS84 (zero at the equator, "
289 "negative values for southern latitudes)"), NULL);
290 gst_tag_register (GST_TAG_GEO_LOCATION_LONGITUDE, GST_TAG_FLAG_META,
291 G_TYPE_DOUBLE, _("geo location longitude"),
292 _("geo longitude location of where the media has been recorded or "
293 "produced in degrees according to WGS84 (zero at the prime meridian "
294 "in Greenwich/UK, negative values for western longitudes)"), NULL);
295 gst_tag_register (GST_TAG_GEO_LOCATION_ELEVATION, GST_TAG_FLAG_META,
296 G_TYPE_DOUBLE, _("geo location elevation"),
297 _("geo elevation of where the media has been recorded or produced in "
298 "meters according to WGS84 (zero is average sea level)"), NULL);
299 gst_tag_register (GST_TAG_GEO_LOCATION_COUNTRY, GST_TAG_FLAG_META,
300 G_TYPE_STRING, _("geo location country"),
301 _("country (english name) where the media has been recorded "
302 "or produced"), NULL);
303 gst_tag_register (GST_TAG_GEO_LOCATION_CITY, GST_TAG_FLAG_META,
304 G_TYPE_STRING, _("geo location city"),
305 _("city (english name) where the media has been recorded "
306 "or produced"), NULL);
307 gst_tag_register (GST_TAG_GEO_LOCATION_SUBLOCATION, GST_TAG_FLAG_META,
308 G_TYPE_STRING, _("geo location sublocation"),
309 _("a location whithin a city where the media has been produced "
310 "or created (e.g. the neighborhood)"), NULL);
311 gst_tag_register (GST_TAG_GEO_LOCATION_HORIZONTAL_ERROR, GST_TAG_FLAG_META,
312 G_TYPE_DOUBLE, _("geo location horizontal error"),
313 _("expected error of the horizontal positioning measures (in meters)"),
315 gst_tag_register (GST_TAG_GEO_LOCATION_MOVEMENT_SPEED, GST_TAG_FLAG_META,
316 G_TYPE_DOUBLE, _("geo location movement speed"),
317 _("movement speed of the capturing device while performing the capture "
319 gst_tag_register (GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION, GST_TAG_FLAG_META,
320 G_TYPE_DOUBLE, _("geo location movement direction"),
321 _("indicates the movement direction of the device performing the capture"
322 " of a media. It is represented as degrees in floating point "
323 "representation, 0 means the geographic north, and increases "
325 gst_tag_register (GST_TAG_GEO_LOCATION_CAPTURE_DIRECTION, GST_TAG_FLAG_META,
326 G_TYPE_DOUBLE, _("geo location capture direction"),
327 _("indicates the direction the device is pointing to when capturing "
328 " a media. It is represented as degrees in floating point "
329 " representation, 0 means the geographic north, and increases "
331 gst_tag_register (GST_TAG_SHOW_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
332 /* TRANSLATORS: 'show name' = 'TV/radio/podcast show name' here */
334 _("Name of the tv/podcast/series show the media is from"),
335 gst_tag_merge_strings_with_comma);
336 gst_tag_register (GST_TAG_SHOW_SORTNAME, GST_TAG_FLAG_META, G_TYPE_STRING,
337 /* TRANSLATORS: 'show sortname' = 'TV/radio/podcast show name as used for sorting purposes' here */
339 _("Name of the tv/podcast/series show the media is from, for sorting "
341 gst_tag_register (GST_TAG_SHOW_EPISODE_NUMBER, GST_TAG_FLAG_META, G_TYPE_UINT,
343 _("The episode number in the season the media is part of"),
344 gst_tag_merge_use_first);
345 gst_tag_register (GST_TAG_SHOW_SEASON_NUMBER, GST_TAG_FLAG_META, G_TYPE_UINT,
347 _("The season number of the show the media is part of"),
348 gst_tag_merge_use_first);
349 gst_tag_register (GST_TAG_LYRICS, GST_TAG_FLAG_META, G_TYPE_STRING,
350 _("lyrics"), _("The lyrics of the media, commonly used for songs"),
351 gst_tag_merge_strings_with_comma);
352 gst_tag_register (GST_TAG_COMPOSER_SORTNAME, GST_TAG_FLAG_META, G_TYPE_STRING,
353 _("composer sortname"),
354 _("person(s) who composed the recording, for sorting purposes"), NULL);
355 gst_tag_register (GST_TAG_GROUPING, GST_TAG_FLAG_META, G_TYPE_STRING,
357 _("Groups related media that spans multiple tracks, like the different "
358 "pieces of a concerto. It is a higher level than a track, "
359 "but lower than an album"), NULL);
360 gst_tag_register (GST_TAG_USER_RATING, GST_TAG_FLAG_META, G_TYPE_UINT,
362 _("Rating attributed by a user. The higher the rank, "
363 "the more the user likes this media"), NULL);
364 gst_tag_register (GST_TAG_DEVICE_MANUFACTURER, GST_TAG_FLAG_META,
365 G_TYPE_STRING, _("device manufacturer"),
366 _("Manufacturer of the device used to create this media"), NULL);
367 gst_tag_register (GST_TAG_DEVICE_MODEL, GST_TAG_FLAG_META, G_TYPE_STRING,
369 _("Model of the device used to create this media"), NULL);
370 gst_tag_register (GST_TAG_APPLICATION_NAME, GST_TAG_FLAG_META, G_TYPE_STRING,
371 _("application name"), _("Application used to create the media"), NULL);
372 gst_tag_register (GST_TAG_APPLICATION_DATA, GST_TAG_FLAG_META,
373 GST_TYPE_BUFFER, _("application data"),
374 _("Arbitrary application data to be serialized into the media"), NULL);
375 gst_tag_register (GST_TAG_IMAGE_ORIENTATION, GST_TAG_FLAG_META, G_TYPE_STRING,
376 _("image orientation"),
377 _("How the image should be rotated or flipped before display"), NULL);
381 * gst_tag_merge_use_first:
382 * @dest: (out caller-allocates): uninitialized GValue to store result in
383 * @src: GValue to copy from
385 * This is a convenience function for the func argument of gst_tag_register().
386 * It creates a copy of the first value from the list.
389 gst_tag_merge_use_first (GValue * dest, const GValue * src)
391 const GValue *ret = gst_value_list_get_value (src, 0);
393 g_value_init (dest, G_VALUE_TYPE (ret));
394 g_value_copy (ret, dest);
398 * gst_tag_merge_strings_with_comma:
399 * @dest: (out caller-allocates): uninitialized GValue to store result in
400 * @src: GValue to copy from
402 * This is a convenience function for the func argument of gst_tag_register().
403 * It concatenates all given strings using a comma. The tag must be registered
404 * as a G_TYPE_STRING or this function will fail.
407 gst_tag_merge_strings_with_comma (GValue * dest, const GValue * src)
412 count = gst_value_list_get_size (src);
413 str = g_string_new (g_value_get_string (gst_value_list_get_value (src, 0)));
414 for (i = 1; i < count; i++) {
415 /* separator between two strings */
416 g_string_append (str, _(", "));
417 g_string_append (str,
418 g_value_get_string (gst_value_list_get_value (src, i)));
421 g_value_init (dest, G_TYPE_STRING);
422 g_value_take_string (dest, str->str);
423 g_string_free (str, FALSE);
427 gst_tag_lookup (const gchar * tag_name)
432 ret = g_hash_table_lookup (__tags, (gpointer) tag_name);
440 * @name: the name or identifier string
441 * @flag: a flag describing the type of tag info
442 * @type: the type this data is in
443 * @nick: human-readable name
444 * @blurb: a human-readable description about this tag
445 * @func: function for merging multiple values of this tag, or NULL
447 * Registers a new tag type for the use with GStreamer's type system. If a type
448 * with that name is already registered, that one is used.
449 * The old registration may have used a different type however. So don't rely
450 * on your supplied values.
452 * Important: if you do not supply a merge function the implication will be
453 * that there can only be one single value for this tag in a tag list and
454 * any additional values will silenty be discarded when being added (unless
455 * #GST_TAG_MERGE_REPLACE, #GST_TAG_MERGE_REPLACE_ALL, or
456 * #GST_TAG_MERGE_PREPEND is used as merge mode, in which case the new
457 * value will replace the old one in the list).
459 * The merge function will be called from gst_tag_list_copy_value() when
460 * it is required that one or more values for a tag be condensed into
461 * one single value. This may happen from gst_tag_list_get_string(),
462 * gst_tag_list_get_int(), gst_tag_list_get_double() etc. What will happen
463 * exactly in that case depends on how the tag was registered and if a
464 * merge function was supplied and if so which one.
466 * Two default merge functions are provided: gst_tag_merge_use_first() and
467 * gst_tag_merge_strings_with_comma().
470 gst_tag_register (const gchar * name, GstTagFlag flag, GType type,
471 const gchar * nick, const gchar * blurb, GstTagMergeFunc func)
476 g_return_if_fail (name != NULL);
477 g_return_if_fail (nick != NULL);
478 g_return_if_fail (blurb != NULL);
479 g_return_if_fail (type != 0 && type != GST_TYPE_LIST);
481 info = gst_tag_lookup (name);
484 g_return_if_fail (info->type == type);
488 info = g_slice_new (GstTagInfo);
491 info->nick = g_strdup (nick);
492 info->blurb = g_strdup (blurb);
493 info->merge_func = func;
495 /* we make a copy for the hash table anyway, which will stay around, so
496 * can use that for the quark table too */
497 name_dup = g_strdup (name);
498 info->name_quark = g_quark_from_static_string (name_dup);
501 g_hash_table_insert (__tags, (gpointer) name_dup, info);
507 * @tag: name of the tag
509 * Checks if the given type is already registered.
511 * Returns: TRUE if the type is already registered
514 gst_tag_exists (const gchar * tag)
516 g_return_val_if_fail (tag != NULL, FALSE);
518 return gst_tag_lookup (tag) != NULL;
525 * Gets the #GType used for this tag.
527 * Returns: the #GType of this tag
530 gst_tag_get_type (const gchar * tag)
534 g_return_val_if_fail (tag != NULL, 0);
535 info = gst_tag_lookup (tag);
536 g_return_val_if_fail (info != NULL, 0);
545 * Returns the human-readable name of this tag, You must not change or free
548 * Returns: the human-readable name of this tag
551 gst_tag_get_nick (const gchar * tag)
555 g_return_val_if_fail (tag != NULL, NULL);
556 info = gst_tag_lookup (tag);
557 g_return_val_if_fail (info != NULL, NULL);
563 * gst_tag_get_description:
566 * Returns the human-readable description of this tag, You must not change or
569 * Returns: the human-readable description of this tag
572 gst_tag_get_description (const gchar * tag)
576 g_return_val_if_fail (tag != NULL, NULL);
577 info = gst_tag_lookup (tag);
578 g_return_val_if_fail (info != NULL, NULL);
587 * Gets the flag of @tag.
589 * Returns: the flag of this tag.
592 gst_tag_get_flag (const gchar * tag)
596 g_return_val_if_fail (tag != NULL, GST_TAG_FLAG_UNDEFINED);
597 info = gst_tag_lookup (tag);
598 g_return_val_if_fail (info != NULL, GST_TAG_FLAG_UNDEFINED);
607 * Checks if the given tag is fixed. A fixed tag can only contain one value.
608 * Unfixed tags can contain lists of values.
610 * Returns: TRUE, if the given tag is fixed.
613 gst_tag_is_fixed (const gchar * tag)
617 g_return_val_if_fail (tag != NULL, FALSE);
618 info = gst_tag_lookup (tag);
619 g_return_val_if_fail (info != NULL, FALSE);
621 return info->merge_func == NULL;
625 * gst_tag_list_new_empty:
627 * Creates a new empty GstTagList.
629 * Free-function: gst_tag_list_free
631 * Returns: (transfer full): An empty tag list
634 gst_tag_list_new_empty (void)
636 return GST_TAG_LIST (gst_structure_new_id_empty (GST_QUARK (TAGLIST)));
642 * @...: NULL-terminated list of values to set
644 * Creates a new taglist and appends the values for the given tags. It expects
645 * tag-value pairs like gst_tag_list_add(), and a NULL terminator after the
646 * last pair. The type of the values is implicit and is documented in the API
647 * reference, but can also be queried at runtime with gst_tag_get_type(). It
648 * is an error to pass a value of a type not matching the tag type into this
649 * function. The tag list will make copies of any arguments passed
650 * (e.g. strings, buffers).
652 * Free-function: gst_tag_list_free
654 * Returns: (transfer full): a new #GstTagList. Free with gst_tag_list_free()
655 * when no longer needed.
660 gst_tag_list_new (const gchar * tag, ...)
665 g_return_val_if_fail (tag != NULL, NULL);
667 list = gst_tag_list_new_empty ();
668 va_start (args, tag);
669 gst_tag_list_add_valist (list, GST_TAG_MERGE_APPEND, tag, args);
676 * gst_tag_list_new_valist:
677 * @var_args: tag / value pairs to set
679 * Just like gst_tag_list_new(), only that it takes a va_list argument.
680 * Useful mostly for language bindings.
682 * Free-function: gst_tag_list_free
684 * Returns: (transfer full): a new #GstTagList. Free with gst_tag_list_free()
685 * when no longer needed.
690 gst_tag_list_new_valist (va_list var_args)
695 list = gst_tag_list_new_empty ();
697 tag = va_arg (var_args, gchar *);
698 gst_tag_list_add_valist (list, GST_TAG_MERGE_APPEND, tag, var_args);
704 * gst_tag_list_to_string:
705 * @list: a #GstTagList
707 * Serializes a tag list to a string.
709 * Returns: a newly-allocated string, or NULL in case of an error. The
710 * string must be freed with g_free() when no longer needed.
715 gst_tag_list_to_string (const GstTagList * list)
717 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
719 return gst_structure_to_string (GST_STRUCTURE (list));
723 * gst_tag_list_new_from_string:
724 * @str: a string created with gst_tag_list_to_string()
726 * Deserializes a tag list.
728 * Returns: a new #GstTagList, or NULL in case of an error.
733 gst_tag_list_new_from_string (const gchar * str)
735 g_return_val_if_fail (str != NULL, NULL);
736 g_return_val_if_fail (g_str_has_prefix (str, "taglist"), NULL);
738 return GST_TAG_LIST (gst_structure_from_string (str, NULL));
742 * gst_tag_list_n_tags:
743 * @list: A #GstTagList.
745 * Get the number of tags in @list.
747 * Returns: The number of tags in @list.
750 gst_tag_list_n_tags (const GstTagList * list)
752 g_return_val_if_fail (list != NULL, 0);
753 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
755 return gst_structure_n_fields ((GstStructure *) list);
759 * gst_tag_list_nth_tag_name:
760 * @list: A #GstTagList.
763 * Get the name of the tag in @list at @index.
765 * Returns: The name of the tag at @index.
768 gst_tag_list_nth_tag_name (const GstTagList * list, guint index)
770 g_return_val_if_fail (list != NULL, 0);
771 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
773 return gst_structure_nth_field_name ((GstStructure *) list, index);
777 * gst_tag_list_is_empty:
778 * @list: A #GstTagList.
780 * Checks if the given taglist is empty.
782 * Returns: TRUE if the taglist is empty, otherwise FALSE.
787 gst_tag_list_is_empty (const GstTagList * list)
789 g_return_val_if_fail (list != NULL, FALSE);
790 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
792 return (gst_structure_n_fields ((GstStructure *) list) == 0);
796 gst_tag_list_fields_equal (const GValue * value1, const GValue * value2)
800 if (gst_value_compare (value1, value2) == GST_VALUE_EQUAL)
803 /* fields not equal: add some tolerance for doubles, otherwise bail out */
804 if (!G_VALUE_HOLDS_DOUBLE (value1) || !G_VALUE_HOLDS_DOUBLE (value2))
807 d1 = g_value_get_double (value1);
808 d2 = g_value_get_double (value2);
810 /* This will only work for 'normal' values and values around 0,
811 * which should be good enough for our purposes here
812 * FIXME: maybe add this to gst_value_compare_double() ? */
813 return (fabs (d1 - d2) < 0.0000001);
817 * gst_tag_list_is_equal:
818 * @list1: a #GstTagList.
819 * @list2: a #GstTagList.
821 * Checks if the two given taglists are equal.
823 * Returns: TRUE if the taglists are equal, otherwise FALSE
828 gst_tag_list_is_equal (const GstTagList * list1, const GstTagList * list2)
830 const GstStructure *s1, *s2;
831 gint num_fields1, num_fields2, i;
833 g_return_val_if_fail (GST_IS_TAG_LIST (list1), FALSE);
834 g_return_val_if_fail (GST_IS_TAG_LIST (list2), FALSE);
836 /* we don't just use gst_structure_is_equal() here so we can add some
837 * tolerance for doubles, though maybe we should just add that to
838 * gst_value_compare_double() as well? */
839 s1 = (const GstStructure *) list1;
840 s2 = (const GstStructure *) list2;
842 num_fields1 = gst_structure_n_fields (s1);
843 num_fields2 = gst_structure_n_fields (s2);
845 if (num_fields1 != num_fields2)
848 for (i = 0; i < num_fields1; i++) {
849 const GValue *value1, *value2;
850 const gchar *tag_name;
852 tag_name = gst_structure_nth_field_name (s1, i);
853 value1 = gst_structure_get_value (s1, tag_name);
854 value2 = gst_structure_get_value (s2, tag_name);
859 if (!gst_tag_list_fields_equal (value1, value2))
868 * @p: Object that might be a taglist
870 * Checks if the given pointer is a taglist.
872 * Returns: TRUE, if the given pointer is a taglist
875 gst_is_tag_list (gconstpointer p)
877 GstStructure *s = (GstStructure *) p;
879 g_return_val_if_fail (p != NULL, FALSE);
881 return (GST_IS_STRUCTURE (s) && s->name == GST_QUARK (TAGLIST));
887 GstTagMergeMode mode;
892 gst_tag_list_add_value_internal (GstTagList * tag_list, GstTagMergeMode mode,
893 const gchar * tag, const GValue * value, GstTagInfo * info)
895 GstStructure *list = GST_STRUCTURE (tag_list);
896 const GValue *value2;
900 info = gst_tag_lookup (tag);
901 if (G_UNLIKELY (info == NULL)) {
902 g_warning ("unknown tag '%s'", tag);
907 tag_quark = info->name_quark;
910 && (value2 = gst_structure_id_get_value (list, tag_quark)) != NULL) {
911 GValue dest = { 0, };
914 case GST_TAG_MERGE_REPLACE_ALL:
915 case GST_TAG_MERGE_REPLACE:
916 gst_structure_id_set_value (list, tag_quark, value);
918 case GST_TAG_MERGE_PREPEND:
919 gst_value_list_merge (&dest, value, value2);
920 gst_structure_id_set_value (list, tag_quark, &dest);
921 g_value_unset (&dest);
923 case GST_TAG_MERGE_APPEND:
924 gst_value_list_merge (&dest, value2, value);
925 gst_structure_id_set_value (list, tag_quark, &dest);
926 g_value_unset (&dest);
928 case GST_TAG_MERGE_KEEP:
929 case GST_TAG_MERGE_KEEP_ALL:
932 g_assert_not_reached ();
937 case GST_TAG_MERGE_APPEND:
938 case GST_TAG_MERGE_KEEP:
939 if (gst_structure_id_get_value (list, tag_quark) != NULL)
942 case GST_TAG_MERGE_REPLACE_ALL:
943 case GST_TAG_MERGE_REPLACE:
944 case GST_TAG_MERGE_PREPEND:
945 gst_structure_id_set_value (list, tag_quark, value);
947 case GST_TAG_MERGE_KEEP_ALL:
950 g_assert_not_reached ();
957 gst_tag_list_copy_foreach (GQuark tag_quark, const GValue * value,
960 GstTagCopyData *copy = (GstTagCopyData *) user_data;
963 tag = g_quark_to_string (tag_quark);
964 gst_tag_list_add_value_internal (copy->list, copy->mode, tag, value, NULL);
970 * gst_tag_list_insert:
971 * @into: list to merge into
972 * @from: list to merge from
973 * @mode: the mode to use
975 * Inserts the tags of the @from list into the first list using the given mode.
978 gst_tag_list_insert (GstTagList * into, const GstTagList * from,
979 GstTagMergeMode mode)
983 g_return_if_fail (GST_IS_TAG_LIST (into));
984 g_return_if_fail (GST_IS_TAG_LIST (from));
985 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
989 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
990 gst_structure_remove_all_fields (GST_STRUCTURE (data.list));
992 gst_structure_foreach ((GstStructure *) from, gst_tag_list_copy_foreach,
998 * @list: list to copy
1000 * Copies a given #GstTagList.
1002 * Free-function: gst_tag_list_free
1004 * Returns: (transfer full): copy of the given list
1007 gst_tag_list_copy (const GstTagList * list)
1009 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
1011 return GST_TAG_LIST (gst_structure_copy ((GstStructure *) list));
1015 * gst_tag_list_merge:
1016 * @list1: first list to merge
1017 * @list2: second list to merge
1018 * @mode: the mode to use
1020 * Merges the two given lists into a new list. If one of the lists is NULL, a
1021 * copy of the other is returned. If both lists are NULL, NULL is returned.
1023 * Free-function: gst_tag_list_free
1025 * Returns: (transfer full): the new list
1028 gst_tag_list_merge (const GstTagList * list1, const GstTagList * list2,
1029 GstTagMergeMode mode)
1031 GstTagList *list1_cp;
1032 const GstTagList *list2_cp;
1034 g_return_val_if_fail (list1 == NULL || GST_IS_TAG_LIST (list1), NULL);
1035 g_return_val_if_fail (list2 == NULL || GST_IS_TAG_LIST (list2), NULL);
1036 g_return_val_if_fail (GST_TAG_MODE_IS_VALID (mode), NULL);
1038 /* nothing to merge */
1039 if (!list1 && !list2) {
1043 /* create empty list, we need to do this to correctly handling merge modes */
1044 list1_cp = (list1) ? gst_tag_list_copy (list1) : gst_tag_list_new_empty ();
1045 list2_cp = (list2) ? list2 : gst_tag_list_new_empty ();
1047 gst_tag_list_insert (list1_cp, list2_cp, mode);
1050 gst_tag_list_free ((GstTagList *) list2_cp);
1056 * gst_tag_list_free:
1057 * @list: (in) (transfer full): the list to free
1059 * Frees the given list and all associated values.
1062 gst_tag_list_free (GstTagList * list)
1064 g_return_if_fail (GST_IS_TAG_LIST (list));
1065 gst_structure_free ((GstStructure *) list);
1069 * gst_tag_list_get_tag_size:
1071 * @tag: the tag to query
1073 * Checks how many value are stored in this tag list for the given tag.
1075 * Returns: The number of tags stored
1078 gst_tag_list_get_tag_size (const GstTagList * list, const gchar * tag)
1080 const GValue *value;
1082 g_return_val_if_fail (GST_IS_TAG_LIST (list), 0);
1084 value = gst_structure_get_value ((GstStructure *) list, tag);
1087 if (G_VALUE_TYPE (value) != GST_TYPE_LIST)
1090 return gst_value_list_get_size (value);
1095 * @list: list to set tags in
1096 * @mode: the mode to use
1098 * @...: NULL-terminated list of values to set
1100 * Sets the values for the given tags using the specified mode.
1103 gst_tag_list_add (GstTagList * list, GstTagMergeMode mode, const gchar * tag,
1108 g_return_if_fail (GST_IS_TAG_LIST (list));
1109 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1110 g_return_if_fail (tag != NULL);
1112 va_start (args, tag);
1113 gst_tag_list_add_valist (list, mode, tag, args);
1118 * gst_tag_list_add_values:
1119 * @list: list to set tags in
1120 * @mode: the mode to use
1122 * @...: GValues to set
1124 * Sets the GValues for the given tags using the specified mode.
1127 gst_tag_list_add_values (GstTagList * list, GstTagMergeMode mode,
1128 const gchar * tag, ...)
1132 g_return_if_fail (GST_IS_TAG_LIST (list));
1133 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1134 g_return_if_fail (tag != NULL);
1136 va_start (args, tag);
1137 gst_tag_list_add_valist_values (list, mode, tag, args);
1142 * gst_tag_list_add_valist:
1143 * @list: list to set tags in
1144 * @mode: the mode to use
1146 * @var_args: tag / value pairs to set
1148 * Sets the values for the given tags using the specified mode.
1151 gst_tag_list_add_valist (GstTagList * list, GstTagMergeMode mode,
1152 const gchar * tag, va_list var_args)
1155 gchar *error = NULL;
1157 g_return_if_fail (GST_IS_TAG_LIST (list));
1158 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1159 g_return_if_fail (tag != NULL);
1161 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
1162 gst_structure_remove_all_fields (GST_STRUCTURE (list));
1165 while (tag != NULL) {
1166 GValue value = { 0, };
1168 info = gst_tag_lookup (tag);
1169 if (G_UNLIKELY (info == NULL)) {
1170 g_warning ("unknown tag '%s'", tag);
1173 G_VALUE_COLLECT_INIT (&value, info->type, var_args, 0, &error);
1175 g_warning ("%s: %s", G_STRLOC, error);
1177 /* we purposely leak the value here, it might not be
1178 * in a sane state if an error condition occoured
1182 gst_tag_list_add_value_internal (list, mode, tag, &value, info);
1183 g_value_unset (&value);
1184 tag = va_arg (var_args, gchar *);
1189 * gst_tag_list_add_valist_values:
1190 * @list: list to set tags in
1191 * @mode: the mode to use
1193 * @var_args: tag / GValue pairs to set
1195 * Sets the GValues for the given tags using the specified mode.
1198 gst_tag_list_add_valist_values (GstTagList * list, GstTagMergeMode mode,
1199 const gchar * tag, va_list var_args)
1201 g_return_if_fail (GST_IS_TAG_LIST (list));
1202 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1203 g_return_if_fail (tag != NULL);
1205 if (mode == GST_TAG_MERGE_REPLACE_ALL) {
1206 gst_structure_remove_all_fields (GST_STRUCTURE (list));
1209 while (tag != NULL) {
1212 info = gst_tag_lookup (tag);
1213 if (G_UNLIKELY (info == NULL)) {
1214 g_warning ("unknown tag '%s'", tag);
1217 gst_tag_list_add_value_internal (list, mode, tag, va_arg (var_args,
1219 tag = va_arg (var_args, gchar *);
1224 * gst_tag_list_add_value:
1225 * @list: list to set tags in
1226 * @mode: the mode to use
1228 * @value: GValue for this tag
1230 * Sets the GValue for a given tag using the specified mode.
1235 gst_tag_list_add_value (GstTagList * list, GstTagMergeMode mode,
1236 const gchar * tag, const GValue * value)
1238 g_return_if_fail (GST_IS_TAG_LIST (list));
1239 g_return_if_fail (GST_TAG_MODE_IS_VALID (mode));
1240 g_return_if_fail (tag != NULL);
1242 gst_tag_list_add_value_internal (list, mode, tag, value, NULL);
1246 * gst_tag_list_remove_tag:
1247 * @list: list to remove tag from
1248 * @tag: tag to remove
1250 * Removes the given tag from the taglist.
1253 gst_tag_list_remove_tag (GstTagList * list, const gchar * tag)
1255 g_return_if_fail (GST_IS_TAG_LIST (list));
1256 g_return_if_fail (tag != NULL);
1258 gst_structure_remove_field ((GstStructure *) list, tag);
1263 GstTagForeachFunc func;
1264 const GstTagList *tag_list;
1270 structure_foreach_wrapper (GQuark field_id, const GValue * value,
1273 TagForeachData *data = (TagForeachData *) user_data;
1275 data->func (data->tag_list, g_quark_to_string (field_id), data->data);
1280 * gst_tag_list_foreach:
1281 * @list: list to iterate over
1282 * @func: (scope call): function to be called for each tag
1283 * @user_data: (closure): user specified data
1285 * Calls the given function for each tag inside the tag list. Note that if there
1286 * is no tag, the function won't be called at all.
1289 gst_tag_list_foreach (const GstTagList * list, GstTagForeachFunc func,
1292 TagForeachData data;
1294 g_return_if_fail (GST_IS_TAG_LIST (list));
1295 g_return_if_fail (func != NULL);
1298 data.tag_list = list;
1299 data.data = user_data;
1300 gst_structure_foreach ((GstStructure *) list, structure_foreach_wrapper,
1305 * gst_tag_list_get_value_index:
1306 * @list: a #GstTagList
1307 * @tag: tag to read out
1308 * @index: number of entry to read out
1310 * Gets the value that is at the given index for the given tag in the given
1313 * Returns: (transfer none): The GValue for the specified entry or NULL if the
1314 * tag wasn't available or the tag doesn't have as many entries
1317 gst_tag_list_get_value_index (const GstTagList * list, const gchar * tag,
1320 const GValue *value;
1322 g_return_val_if_fail (GST_IS_TAG_LIST (list), NULL);
1323 g_return_val_if_fail (tag != NULL, NULL);
1325 value = gst_structure_get_value ((GstStructure *) list, tag);
1329 if (GST_VALUE_HOLDS_LIST (value)) {
1330 if (index >= gst_value_list_get_size (value))
1332 return gst_value_list_get_value (value, index);
1341 * gst_tag_list_copy_value:
1342 * @dest: (out caller-allocates): uninitialized #GValue to copy into
1343 * @list: list to get the tag from
1344 * @tag: tag to read out
1346 * Copies the contents for the given tag into the value,
1347 * merging multiple values into one if multiple values are associated
1349 * You must g_value_unset() the value after use.
1351 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1355 gst_tag_list_copy_value (GValue * dest, const GstTagList * list,
1360 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1361 g_return_val_if_fail (tag != NULL, FALSE);
1362 g_return_val_if_fail (dest != NULL, FALSE);
1363 g_return_val_if_fail (G_VALUE_TYPE (dest) == 0, FALSE);
1365 src = gst_structure_get_value ((GstStructure *) list, tag);
1369 if (G_VALUE_TYPE (src) == GST_TYPE_LIST) {
1370 GstTagInfo *info = gst_tag_lookup (tag);
1375 /* must be there or lists aren't allowed */
1376 g_assert (info->merge_func);
1377 info->merge_func (dest, src);
1379 g_value_init (dest, G_VALUE_TYPE (src));
1380 g_value_copy (src, dest);
1385 /* FIXME 0.11: this whole merge function business is overdesigned, and the
1386 * _get_foo() API is misleading as well - how many application developers will
1387 * expect gst_tag_list_get_string (list, GST_TAG_ARTIST, &val) might return a
1388 * string with multiple comma-separated artists? _get_foo() should just be
1389 * a convenience wrapper around _get_foo_index (list, tag, 0, &val),
1390 * supplemented by a special _tag_list_get_string_merged() function if needed
1391 * (unless someone can actually think of real use cases where the merge
1392 * function is not 'use first' for non-strings and merge for strings) */
1394 /***** evil macros to get all the gst_tag_list_get_*() functions right *****/
1396 #define TAG_MERGE_FUNCS(name,type,ret) \
1398 gst_tag_list_get_ ## name (const GstTagList *list, const gchar *tag, \
1401 GValue v = { 0, }; \
1403 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
1404 g_return_val_if_fail (tag != NULL, FALSE); \
1405 g_return_val_if_fail (value != NULL, FALSE); \
1407 if (!gst_tag_list_copy_value (&v, list, tag)) \
1409 *value = COPY_FUNC (g_value_get_ ## name (&v)); \
1410 g_value_unset (&v); \
1415 gst_tag_list_get_ ## name ## _index (const GstTagList *list, \
1417 guint index, type *value) \
1421 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE); \
1422 g_return_val_if_fail (tag != NULL, FALSE); \
1423 g_return_val_if_fail (value != NULL, FALSE); \
1425 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL) \
1427 *value = COPY_FUNC (g_value_get_ ## name (v)); \
1431 #define COPY_FUNC /**/
1433 * gst_tag_list_get_boolean:
1434 * @list: a #GstTagList to get the tag from
1435 * @tag: tag to read out
1436 * @value: (out): location for the result
1438 * Copies the contents for the given tag into the value, merging multiple values
1439 * into one if multiple values are associated with the tag.
1441 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1445 * gst_tag_list_get_boolean_index:
1446 * @list: a #GstTagList to get the tag from
1447 * @tag: tag to read out
1448 * @index: number of entry to read out
1449 * @value: (out): location for the result
1451 * Gets the value that is at the given index for the given tag in the given
1454 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1457 TAG_MERGE_FUNCS (boolean, gboolean, TRUE);
1459 * gst_tag_list_get_int:
1460 * @list: a #GstTagList to get the tag from
1461 * @tag: tag to read out
1462 * @value: (out): location for the result
1464 * Copies the contents for the given tag into the value, merging multiple values
1465 * into one if multiple values are associated with the tag.
1467 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1471 * gst_tag_list_get_int_index:
1472 * @list: a #GstTagList to get the tag from
1473 * @tag: tag to read out
1474 * @index: number of entry to read out
1475 * @value: (out): location for the result
1477 * Gets the value that is at the given index for the given tag in the given
1480 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1483 TAG_MERGE_FUNCS (int, gint, TRUE);
1485 * gst_tag_list_get_uint:
1486 * @list: a #GstTagList to get the tag from
1487 * @tag: tag to read out
1488 * @value: (out): location for the result
1490 * Copies the contents for the given tag into the value, merging multiple values
1491 * into one if multiple values are associated with the tag.
1493 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1497 * gst_tag_list_get_uint_index:
1498 * @list: a #GstTagList to get the tag from
1499 * @tag: tag to read out
1500 * @index: number of entry to read out
1501 * @value: (out): location for the result
1503 * Gets the value that is at the given index for the given tag in the given
1506 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1509 TAG_MERGE_FUNCS (uint, guint, TRUE);
1511 * gst_tag_list_get_int64_index:
1512 * @list: a #GstTagList to get the tag from
1513 * @tag: tag to read out
1514 * @index: number of entry to read out
1515 * @value: (out): location for the result
1517 * Gets the value that is at the given index for the given tag in the given
1520 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1523 TAG_MERGE_FUNCS (int64, gint64, TRUE);
1525 * gst_tag_list_get_uint64:
1526 * @list: a #GstTagList to get the tag from
1527 * @tag: tag to read out
1528 * @value: (out): location for the result
1530 * Copies the contents for the given tag into the value, merging multiple values
1531 * into one if multiple values are associated with the tag.
1533 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1537 * gst_tag_list_get_uint64_index:
1538 * @list: a #GstTagList to get the tag from
1539 * @tag: tag to read out
1540 * @index: number of entry to read out
1541 * @value: (out): location for the result
1543 * Gets the value that is at the given index for the given tag in the given
1546 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1549 TAG_MERGE_FUNCS (uint64, guint64, TRUE);
1551 * gst_tag_list_get_float:
1552 * @list: a #GstTagList to get the tag from
1553 * @tag: tag to read out
1554 * @value: (out): location for the result
1556 * Copies the contents for the given tag into the value, merging multiple values
1557 * into one if multiple values are associated with the tag.
1559 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1563 * gst_tag_list_get_float_index:
1564 * @list: a #GstTagList to get the tag from
1565 * @tag: tag to read out
1566 * @index: number of entry to read out
1567 * @value: (out): location for the result
1569 * Gets the value that is at the given index for the given tag in the given
1572 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1575 TAG_MERGE_FUNCS (float, gfloat, TRUE);
1577 * gst_tag_list_get_double:
1578 * @list: a #GstTagList to get the tag from
1579 * @tag: tag to read out
1580 * @value: (out): location for the result
1582 * Copies the contents for the given tag into the value, merging multiple values
1583 * into one if multiple values are associated with the tag.
1585 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1589 * gst_tag_list_get_double_index:
1590 * @list: a #GstTagList to get the tag from
1591 * @tag: tag to read out
1592 * @index: number of entry to read out
1593 * @value: (out): location for the result
1595 * Gets the value that is at the given index for the given tag in the given
1598 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1601 TAG_MERGE_FUNCS (double, gdouble, TRUE);
1603 * gst_tag_list_get_pointer:
1604 * @list: a #GstTagList to get the tag from
1605 * @tag: tag to read out
1606 * @value: (out) (transfer none): location for the result
1608 * Copies the contents for the given tag into the value, merging multiple values
1609 * into one if multiple values are associated with the tag.
1611 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1615 * gst_tag_list_get_pointer_index:
1616 * @list: a #GstTagList to get the tag from
1617 * @tag: tag to read out
1618 * @index: number of entry to read out
1619 * @value: (out) (transfer none): location for the result
1621 * Gets the value that is at the given index for the given tag in the given
1624 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1627 TAG_MERGE_FUNCS (pointer, gpointer, (*value != NULL));
1629 static inline gchar *
1630 _gst_strdup0 (const gchar * s)
1632 if (s == NULL || *s == '\0')
1635 return g_strdup (s);
1639 #define COPY_FUNC _gst_strdup0
1642 * gst_tag_list_get_string:
1643 * @list: a #GstTagList to get the tag from
1644 * @tag: tag to read out
1645 * @value: (out callee-allocates) (transfer full): location for the result
1647 * Copies the contents for the given tag into the value, possibly merging
1648 * multiple values into one if multiple values are associated with the tag.
1650 * Use gst_tag_list_get_string_index (list, tag, 0, value) if you want
1651 * to retrieve the first string associated with this tag unmodified.
1653 * The resulting string in @value will be in UTF-8 encoding and should be
1654 * freed by the caller using g_free when no longer needed. Since 0.10.24 the
1655 * returned string is also guaranteed to be non-NULL and non-empty.
1657 * Free-function: g_free
1659 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1663 * gst_tag_list_get_string_index:
1664 * @list: a #GstTagList to get the tag from
1665 * @tag: tag to read out
1666 * @index: number of entry to read out
1667 * @value: (out callee-allocates) (transfer full): location for the result
1669 * Gets the value that is at the given index for the given tag in the given
1672 * The resulting string in @value will be in UTF-8 encoding and should be
1673 * freed by the caller using g_free when no longer needed. Since 0.10.24 the
1674 * returned string is also guaranteed to be non-NULL and non-empty.
1676 * Free-function: g_free
1678 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1681 TAG_MERGE_FUNCS (string, gchar *, (*value != NULL));
1684 *FIXME 0.11: Instead of _peek (non-copy) and _get (copy), we could have
1685 * _get (non-copy) and _dup (copy) for strings, seems more
1689 * gst_tag_list_peek_string_index:
1690 * @list: a #GstTagList to get the tag from
1691 * @tag: tag to read out
1692 * @index: number of entry to read out
1693 * @value: (out) (transfer none): location for the result
1695 * Peeks at the value that is at the given index for the given tag in the given
1698 * The resulting string in @value will be in UTF-8 encoding and doesn't need
1699 * to be freed by the caller. The returned string is also guaranteed to
1700 * be non-NULL and non-empty.
1702 * Returns: TRUE, if a value was set, FALSE if the tag didn't exist in the
1706 gst_tag_list_peek_string_index (const GstTagList * list,
1707 const gchar * tag, guint index, const gchar ** value)
1711 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1712 g_return_val_if_fail (tag != NULL, FALSE);
1713 g_return_val_if_fail (value != NULL, FALSE);
1715 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1717 *value = g_value_get_string (v);
1718 return *value != NULL && **value != '\0';
1722 * gst_tag_list_get_date:
1723 * @list: a #GstTagList to get the tag from
1724 * @tag: tag to read out
1725 * @value: (out callee-allocates) (transfer full): address of a GDate pointer
1726 * variable to store the result into
1728 * Copies the first date for the given tag in the taglist into the variable
1729 * pointed to by @value. Free the date with g_date_free() when it is no longer
1732 * Free-function: g_date_free
1734 * Returns: TRUE, if a date was copied, FALSE if the tag didn't exist in the
1735 * given list or if it was #NULL.
1738 gst_tag_list_get_date (const GstTagList * list, const gchar * tag,
1743 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1744 g_return_val_if_fail (tag != NULL, FALSE);
1745 g_return_val_if_fail (value != NULL, FALSE);
1747 if (!gst_tag_list_copy_value (&v, list, tag))
1749 *value = (GDate *) g_value_dup_boxed (&v);
1751 return (*value != NULL);
1755 * gst_tag_list_get_date_index:
1756 * @list: a #GstTagList to get the tag from
1757 * @tag: tag to read out
1758 * @index: number of entry to read out
1759 * @value: (out callee-allocates) (transfer full): location for the result
1761 * Gets the date that is at the given index for the given tag in the given
1762 * list and copies it into the variable pointed to by @value. Free the date
1763 * with g_date_free() when it is no longer needed.
1765 * Free-function: g_date_free
1767 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1768 * given list or if it was #NULL.
1771 gst_tag_list_get_date_index (const GstTagList * list,
1772 const gchar * tag, guint index, GDate ** value)
1776 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1777 g_return_val_if_fail (tag != NULL, FALSE);
1778 g_return_val_if_fail (value != NULL, FALSE);
1780 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1782 *value = (GDate *) g_value_dup_boxed (v);
1783 return (*value != NULL);
1787 * gst_tag_list_get_date_time:
1788 * @list: a #GstTagList to get the tag from
1789 * @tag: tag to read out
1790 * @value: (out callee-allocates) (transfer full): address of a #GstDateTime
1791 * pointer variable to store the result into
1793 * Copies the first datetime for the given tag in the taglist into the variable
1794 * pointed to by @value. Unref the date with gst_date_time_unref() when
1795 * it is no longer needed.
1797 * Free-function: gst_date_time_unref
1799 * Returns: TRUE, if a datetime was copied, FALSE if the tag didn't exist in
1800 * thegiven list or if it was #NULL.
1805 gst_tag_list_get_date_time (const GstTagList * list, const gchar * tag,
1806 GstDateTime ** value)
1810 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1811 g_return_val_if_fail (tag != NULL, FALSE);
1812 g_return_val_if_fail (value != NULL, FALSE);
1814 if (!gst_tag_list_copy_value (&v, list, tag))
1817 g_return_val_if_fail (GST_VALUE_HOLDS_DATE_TIME (&v), FALSE);
1819 *value = (GstDateTime *) g_value_dup_boxed (&v);
1821 return (*value != NULL);
1825 * gst_tag_list_get_date_time_index:
1826 * @list: a #GstTagList to get the tag from
1827 * @tag: tag to read out
1828 * @index: number of entry to read out
1829 * @value: (out callee-allocates) (transfer full): location for the result
1831 * Gets the datetime that is at the given index for the given tag in the given
1832 * list and copies it into the variable pointed to by @value. Unref the datetime
1833 * with gst_date_time_unref() when it is no longer needed.
1835 * Free-function: gst_date_time_unref
1837 * Returns: TRUE, if a value was copied, FALSE if the tag didn't exist in the
1838 * given list or if it was #NULL.
1843 gst_tag_list_get_date_time_index (const GstTagList * list,
1844 const gchar * tag, guint index, GstDateTime ** value)
1848 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1849 g_return_val_if_fail (tag != NULL, FALSE);
1850 g_return_val_if_fail (value != NULL, FALSE);
1852 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1854 *value = (GstDateTime *) g_value_dup_boxed (v);
1855 return (*value != NULL);
1859 * gst_tag_list_get_buffer:
1860 * @list: a #GstTagList to get the tag from
1861 * @tag: tag to read out
1862 * @value: (out callee-allocates) (transfer full): address of a GstBuffer
1863 * pointer variable to store the result into
1865 * Copies the first buffer for the given tag in the taglist into the variable
1866 * pointed to by @value. Free the buffer with gst_buffer_unref() when it is
1869 * Free-function: gst_buffer_unref
1871 * Returns: TRUE, if a buffer was copied, FALSE if the tag didn't exist in the
1872 * given list or if it was #NULL.
1877 gst_tag_list_get_buffer (const GstTagList * list, const gchar * tag,
1882 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1883 g_return_val_if_fail (tag != NULL, FALSE);
1884 g_return_val_if_fail (value != NULL, FALSE);
1886 if (!gst_tag_list_copy_value (&v, list, tag))
1888 *value = g_value_dup_boxed (&v);
1890 return (*value != NULL);
1894 * gst_tag_list_get_buffer_index:
1895 * @list: a #GstTagList to get the tag from
1896 * @tag: tag to read out
1897 * @index: number of entry to read out
1898 * @value: (out callee-allocates) (transfer full): address of a GstBuffer
1899 * pointer variable to store the result into
1901 * Gets the buffer that is at the given index for the given tag in the given
1902 * list and copies it into the variable pointed to by @value. Free the buffer
1903 * with gst_buffer_unref() when it is no longer needed.
1905 * Free-function: gst_buffer_unref
1907 * Returns: TRUE, if a buffer was copied, FALSE if the tag didn't exist in the
1908 * given list or if it was #NULL.
1913 gst_tag_list_get_buffer_index (const GstTagList * list,
1914 const gchar * tag, guint index, GstBuffer ** value)
1918 g_return_val_if_fail (GST_IS_TAG_LIST (list), FALSE);
1919 g_return_val_if_fail (tag != NULL, FALSE);
1920 g_return_val_if_fail (value != NULL, FALSE);
1922 if ((v = gst_tag_list_get_value_index (list, tag, index)) == NULL)
1924 *value = g_value_dup_boxed (v);
1925 return (*value != NULL);