1 /* GStreamer non-core tag registration and tag utility functions
2 * Copyright (C) 2005 Ross Burton <ross@burtonini.com>
3 * Copyright (C) 2006-2008 Tim-Philipp Müller <tim centricular net>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 * Boston, MA 02111-1307, USA.
25 #include <gst/gst-i18n-plugin.h>
26 #include <gst/base/gsttypefindhelper.h>
34 * @short_description: additional tag definitions for plugins and applications
35 * @see_also: #GstTagList
39 * Contains additional standardized GStreamer tag definitions for plugins
40 * and applications, and functions to register them with the GStreamer
48 gst_tag_register_tags_internal (gpointer unused)
51 GST_DEBUG ("binding text domain %s to locale dir %s", GETTEXT_PACKAGE,
53 bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
56 /* musicbrainz tags */
57 gst_tag_register (GST_TAG_MUSICBRAINZ_TRACKID, GST_TAG_FLAG_META,
58 G_TYPE_STRING, _("track ID"), _("MusicBrainz track ID"), NULL);
59 gst_tag_register (GST_TAG_MUSICBRAINZ_ARTISTID, GST_TAG_FLAG_META,
60 G_TYPE_STRING, _("artist ID"), _("MusicBrainz artist ID"), NULL);
61 gst_tag_register (GST_TAG_MUSICBRAINZ_ALBUMID, GST_TAG_FLAG_META,
62 G_TYPE_STRING, _("album ID"), _("MusicBrainz album ID"), NULL);
63 gst_tag_register (GST_TAG_MUSICBRAINZ_ALBUMARTISTID, GST_TAG_FLAG_META,
65 _("album artist ID"), _("MusicBrainz album artist ID"), NULL);
66 gst_tag_register (GST_TAG_MUSICBRAINZ_TRMID, GST_TAG_FLAG_META,
67 G_TYPE_STRING, _("track TRM ID"), _("MusicBrainz TRM ID"), NULL);
70 gst_tag_register (GST_TAG_CDDA_CDDB_DISCID, GST_TAG_FLAG_META,
71 G_TYPE_STRING, "discid", "CDDB discid for metadata retrieval",
72 gst_tag_merge_use_first);
74 gst_tag_register (GST_TAG_CDDA_CDDB_DISCID_FULL, GST_TAG_FLAG_META,
75 G_TYPE_STRING, "discid full",
76 "CDDB discid for metadata retrieval (full)", gst_tag_merge_use_first);
78 gst_tag_register (GST_TAG_CDDA_MUSICBRAINZ_DISCID, GST_TAG_FLAG_META,
79 G_TYPE_STRING, "musicbrainz-discid",
80 "Musicbrainz discid for metadata retrieval", gst_tag_merge_use_first);
82 gst_tag_register (GST_TAG_CDDA_MUSICBRAINZ_DISCID_FULL, GST_TAG_FLAG_META,
83 G_TYPE_STRING, "musicbrainz-discid-full",
84 "Musicbrainz discid for metadata retrieval (full)",
85 gst_tag_merge_use_first);
90 /* FIXME 0.11: rename this to gst_tag_init() or gst_tag_register_tags() */
92 * gst_tag_register_musicbrainz_tags
94 * Registers additional musicbrainz-specific tags with the GStreamer tag
95 * system. Plugins and applications that use these tags should call this
96 * function before using them. Can be called multiple times.
99 gst_tag_register_musicbrainz_tags (void)
101 static GOnce mb_once = G_ONCE_INIT;
103 g_once (&mb_once, gst_tag_register_tags_internal, NULL);
107 register_tag_image_type_enum (GType * id)
109 static const GEnumValue image_types[] = {
110 {GST_TAG_IMAGE_TYPE_NONE, "GST_TAG_IMAGE_TYPE_NONE", "none"},
111 {GST_TAG_IMAGE_TYPE_UNDEFINED, "GST_TAG_IMAGE_TYPE_UNDEFINED", "undefined"},
112 {GST_TAG_IMAGE_TYPE_FRONT_COVER, "GST_TAG_IMAGE_TYPE_FRONT_COVER",
114 {GST_TAG_IMAGE_TYPE_BACK_COVER, "GST_TAG_IMAGE_TYPE_BACK_COVER",
116 {GST_TAG_IMAGE_TYPE_LEAFLET_PAGE, "GST_TAG_IMAGE_TYPE_LEAFLET_PAGE",
118 {GST_TAG_IMAGE_TYPE_MEDIUM, "GST_TAG_IMAGE_TYPE_MEDIUM", "medium"},
119 {GST_TAG_IMAGE_TYPE_LEAD_ARTIST, "GST_TAG_IMAGE_TYPE_LEAD_ARTIST",
121 {GST_TAG_IMAGE_TYPE_ARTIST, "GST_TAG_IMAGE_TYPE_ARTIST", "artist"},
122 {GST_TAG_IMAGE_TYPE_CONDUCTOR, "GST_TAG_IMAGE_TYPE_CONDUCTOR", "conductor"},
123 {GST_TAG_IMAGE_TYPE_BAND_ORCHESTRA, "GST_TAG_IMAGE_TYPE_BAND_ORCHESTRA",
125 {GST_TAG_IMAGE_TYPE_COMPOSER, "GST_TAG_IMAGE_TYPE_COMPOSER", "composer"},
126 {GST_TAG_IMAGE_TYPE_LYRICIST, "GST_TAG_IMAGE_TYPE_LYRICIST", "lyricist"},
127 {GST_TAG_IMAGE_TYPE_RECORDING_LOCATION,
128 "GST_TAG_IMAGE_TYPE_RECORDING_LOCATION",
129 "recording-location"},
130 {GST_TAG_IMAGE_TYPE_DURING_RECORDING, "GST_TAG_IMAGE_TYPE_DURING_RECORDING",
132 {GST_TAG_IMAGE_TYPE_DURING_PERFORMANCE,
133 "GST_TAG_IMAGE_TYPE_DURING_PERFORMANCE",
134 "during-performance"},
135 {GST_TAG_IMAGE_TYPE_VIDEO_CAPTURE, "GST_TAG_IMAGE_TYPE_VIDEO_CAPTURE",
137 {GST_TAG_IMAGE_TYPE_FISH, "GST_TAG_IMAGE_TYPE_FISH", "fish"},
138 {GST_TAG_IMAGE_TYPE_ILLUSTRATION, "GST_TAG_IMAGE_TYPE_ILLUSTRATION",
140 {GST_TAG_IMAGE_TYPE_BAND_ARTIST_LOGO, "GST_TAG_IMAGE_TYPE_BAND_ARTIST_LOGO",
142 {GST_TAG_IMAGE_TYPE_PUBLISHER_STUDIO_LOGO,
143 "GST_TAG_IMAGE_TYPE_PUBLISHER_STUDIO_LOGO",
144 "publisher-studio-logo"},
148 *id = g_enum_register_static ("GstTagImageType", image_types);
150 /* work around thread-safety issue with class creation in GLib */
151 g_type_class_ref (*id);
155 gst_tag_image_type_get_type (void)
159 static GOnce once = G_ONCE_INIT;
161 g_once (&once, (GThreadFunc) register_tag_image_type_enum, &id);
165 static inline gboolean
166 gst_tag_image_type_is_valid (GstTagImageType type)
172 klass = g_type_class_ref (gst_tag_image_type_get_type ());
173 res = (g_enum_get_value (klass, type) != NULL);
174 g_type_class_unref (klass);
180 * gst_tag_parse_extended_comment:
181 * @ext_comment: an extended comment string, see #GST_TAG_EXTENDED_COMMENT
182 * @key: return location for the comment description key, or NULL
183 * @lang: return location for the comment ISO-639 language code, or NULL
184 * @value: return location for the actual comment string, or NULL
185 * @fail_if_no_key: whether to fail if strings are not in key=value form
187 * Convenience function to parse a GST_TAG_EXTENDED_COMMENT string and
188 * separate it into its components.
190 * If successful, @key, @lang and/or @value will be set to newly allocated
191 * strings that you need to free with g_free() when done. @key and @lang
192 * may also be set to NULL by this function if there is no key or no language
193 * code in the extended comment string.
195 * Returns: TRUE if the string could be parsed, otherwise FALSE
200 gst_tag_parse_extended_comment (const gchar * ext_comment, gchar ** key,
201 gchar ** lang, gchar ** value, gboolean fail_if_no_key)
203 const gchar *div, *bop, *bcl;
205 g_return_val_if_fail (ext_comment != NULL, FALSE);
206 g_return_val_if_fail (g_utf8_validate (ext_comment, -1, NULL), FALSE);
213 div = strchr (ext_comment, '=');
214 bop = strchr (ext_comment, '[');
215 bcl = strchr (ext_comment, ']');
221 *value = g_strdup (ext_comment);
225 if (bop != NULL && bop < div) {
226 if (bcl < bop || bcl > div)
229 *key = g_strndup (ext_comment, bop - ext_comment);
231 *lang = g_strndup (bop + 1, bcl - bop - 1);
234 *key = g_strndup (ext_comment, div - ext_comment);
238 *value = g_strdup (div + 1);
244 * gst_tag_freeform_string_to_utf8:
246 * @size: length of string data, or -1 if the string is NUL-terminated
247 * @env_vars: a NULL-terminated string array of environment variable names,
250 * Convenience function to read a string with unknown character encoding. If
251 * the string is already in UTF-8 encoding, it will be returned right away.
252 * Otherwise, the environment will be searched for a number of environment
253 * variables (whose names are specified in the NULL-terminated string array
254 * @env_vars) containing a list of character encodings to try/use. If none
255 * are specified, the current locale will be tried. If that also doesn't work,
256 * ISO-8859-1 is assumed (which will almost always succeed).
258 * Returns: a newly-allocated string in UTF-8 encoding, or NULL
263 gst_tag_freeform_string_to_utf8 (const gchar * data, gint size,
264 const gchar ** env_vars)
266 const gchar *cur_loc = NULL;
272 g_return_val_if_fail (data != NULL, NULL);
275 size = strlen (data);
277 /* chop off trailing string terminators to make sure utf8_validate doesn't
278 * get to see them (since that would make the utf8 check fail) */
279 while (size > 0 && data[size - 1] == '\0')
282 /* Should we try the charsets specified
283 * via environment variables FIRST ? */
284 if (g_utf8_validate (data, size, NULL)) {
285 utf8 = g_strndup (data, size);
286 GST_LOG ("String '%s' is valid UTF-8 already", utf8);
290 while (env_vars && *env_vars != NULL) {
291 const gchar *env = NULL;
293 /* Try charsets specified via the environment */
294 env = g_getenv (*env_vars);
295 if (env != NULL && *env != '\0') {
298 csets = g_strsplit (env, G_SEARCHPATH_SEPARATOR_S, -1);
300 for (c = csets; c && *c; ++c) {
301 GST_LOG ("Trying to convert freeform string to UTF-8 from '%s'", *c);
303 g_convert (data, size, "UTF-8", *c, &bytes_read, NULL, NULL))) {
304 if (bytes_read == size) {
318 /* Try current locale (if not UTF-8) */
319 if (!g_get_charset (&cur_loc)) {
320 GST_LOG ("Trying to convert freeform string using locale ('%s')", cur_loc);
321 if ((utf8 = g_locale_to_utf8 (data, size, &bytes_read, NULL, NULL))) {
322 if (bytes_read == size) {
331 GST_LOG ("Trying to convert freeform string using ISO-8859-1 fallback");
332 utf8 = g_convert (data, size, "UTF-8", "ISO-8859-1", &bytes_read, NULL, NULL);
333 if (utf8 != NULL && bytes_read == size) {
343 if (utf8 && utf8[0] != '\0') {
344 GST_LOG ("Returning '%s'", utf8);
353 * gst_tag_image_data_to_image_buffer:
354 * @image_data: the (encoded) image
355 * @image_data_len: the length of the encoded image data at @image_data
356 * @image_type: type of the image, or #GST_TAG_IMAGE_TYPE_UNDEFINED. Pass
357 * #GST_TAG_IMAGE_TYPE_NONE if no image type should be set at all (e.g.
358 * for preview images)
360 * Helper function for tag-reading plugins to create a #GstBuffer suitable to
361 * add to a #GstTagList as an image tag (such as #GST_TAG_IMAGE or
362 * #GST_TAG_PREVIEW_IMAGE) from the encoded image data and an (optional) image
365 * Background: cover art and other images in tags are usually stored as a
366 * blob of binary image data, often accompanied by a MIME type or some other
367 * content type string (e.g. 'png', 'jpeg', 'jpg'). Sometimes there is also an
368 * 'image type' to indicate what kind of image this is (e.g. front cover,
369 * back cover, artist, etc.). The image data may also be an URI to the image
370 * rather than the image itself.
372 * In GStreamer, image tags are #GstBuffer<!-- -->s containing the raw image
373 * data, with the buffer caps describing the content type of the image
374 * (e.g. image/jpeg, image/png, text/uri-list). The buffer caps may contain
375 * an additional 'image-type' field of #GST_TYPE_TAG_IMAGE_TYPE to describe
376 * the type of image (front cover, back cover etc.). #GST_TAG_PREVIEW_IMAGE
377 * tags should not carry an image type, their type is already indicated via
378 * the special tag name.
380 * This function will do various checks and typefind the encoded image
381 * data (we can't trust the declared mime type).
383 * Returns: a newly-allocated image buffer for use in tag lists, or NULL
388 gst_tag_image_data_to_image_buffer (const guint8 * image_data,
389 guint image_data_len, GstTagImageType image_type)
397 g_return_val_if_fail (image_data != NULL, NULL);
398 g_return_val_if_fail (image_data_len > 0, NULL);
399 g_return_val_if_fail (gst_tag_image_type_is_valid (image_type), NULL);
401 GST_DEBUG ("image data len: %u bytes", image_data_len);
403 /* allocate space for a NUL terminator for an uri too */
404 image = gst_buffer_try_new_and_alloc (image_data_len + 1);
406 GST_WARNING ("failed to allocate buffer of %d for image", image_data_len);
410 memcpy (GST_BUFFER_DATA (image), image_data, image_data_len);
411 GST_BUFFER_DATA (image)[image_data_len] = '\0';
412 GST_BUFFER_SIZE (image) = image_data_len;
414 /* Find GStreamer media type, can't trust declared type */
415 caps = gst_type_find_helper_for_buffer (NULL, image, NULL);
420 GST_DEBUG ("Found GStreamer media type: %" GST_PTR_FORMAT, caps);
422 /* sanity check: make sure typefound/declared caps are either URI or image */
423 name = gst_structure_get_name (gst_caps_get_structure (caps, 0));
425 if (!g_str_has_prefix (name, "image/") &&
426 !g_str_has_prefix (name, "video/") &&
427 !g_str_equal (name, "text/uri-list")) {
428 GST_DEBUG ("Unexpected image type '%s', ignoring image frame", name);
432 /* Decrease size by 1 if we don't have an URI list
433 * to keep the original size of the image
435 if (!g_str_equal (name, "text/uri-list"))
436 GST_BUFFER_SIZE (image) = GST_BUFFER_SIZE (image) - 1;
438 if (image_type != GST_TAG_IMAGE_TYPE_NONE) {
439 GST_LOG ("Setting image type: %d", image_type);
440 caps = gst_caps_make_writable (caps);
441 gst_caps_set_simple (caps, "image-type", GST_TYPE_TAG_IMAGE_TYPE,
445 gst_buffer_set_caps (image, caps);
446 gst_caps_unref (caps);
452 GST_DEBUG ("Could not determine GStreamer media type, ignoring image");
458 gst_buffer_unref (image);
460 gst_caps_unref (caps);