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>
35 * @short_description: additional tag definitions for plugins and applications
36 * @see_also: #GstTagList
40 * Contains additional standardized GStreamer tag definitions for plugins
41 * and applications, and functions to register them with the GStreamer
47 #ifndef GST_DISABLE_GST_DEBUG
48 #define GST_CAT_DEFAULT gst_tag_ensure_debug_category()
50 static GstDebugCategory *
51 gst_tag_ensure_debug_category (void)
53 static gsize cat_gonce = 0;
55 if (g_once_init_enter (&cat_gonce)) {
56 GstDebugCategory *cat = NULL;
58 GST_DEBUG_CATEGORY_INIT (cat, "tag-tags", 0, "GstTag helper functions");
60 g_once_init_leave (&cat_gonce, (gsize) cat);
63 return (GstDebugCategory *) cat_gonce;
65 #endif /* GST_DISABLE_GST_DEBUG */
68 gst_tag_register_tags_internal (gpointer unused)
71 GST_DEBUG ("binding text domain %s to locale dir %s", GETTEXT_PACKAGE,
73 bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
74 bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
77 /* musicbrainz tags */
78 gst_tag_register (GST_TAG_MUSICBRAINZ_TRACKID, GST_TAG_FLAG_META,
79 G_TYPE_STRING, _("track ID"), _("MusicBrainz track ID"), NULL);
80 gst_tag_register (GST_TAG_MUSICBRAINZ_ARTISTID, GST_TAG_FLAG_META,
81 G_TYPE_STRING, _("artist ID"), _("MusicBrainz artist ID"), NULL);
82 gst_tag_register (GST_TAG_MUSICBRAINZ_ALBUMID, GST_TAG_FLAG_META,
83 G_TYPE_STRING, _("album ID"), _("MusicBrainz album ID"), NULL);
84 gst_tag_register (GST_TAG_MUSICBRAINZ_ALBUMARTISTID, GST_TAG_FLAG_META,
86 _("album artist ID"), _("MusicBrainz album artist ID"), NULL);
87 gst_tag_register (GST_TAG_MUSICBRAINZ_TRMID, GST_TAG_FLAG_META,
88 G_TYPE_STRING, _("track TRM ID"), _("MusicBrainz TRM ID"), NULL);
91 gst_tag_register (GST_TAG_CDDA_CDDB_DISCID, GST_TAG_FLAG_META,
92 G_TYPE_STRING, "discid", "CDDB discid for metadata retrieval",
93 gst_tag_merge_use_first);
95 gst_tag_register (GST_TAG_CDDA_CDDB_DISCID_FULL, GST_TAG_FLAG_META,
96 G_TYPE_STRING, "discid full",
97 "CDDB discid for metadata retrieval (full)", gst_tag_merge_use_first);
99 gst_tag_register (GST_TAG_CDDA_MUSICBRAINZ_DISCID, GST_TAG_FLAG_META,
100 G_TYPE_STRING, "musicbrainz-discid",
101 "Musicbrainz discid for metadata retrieval", gst_tag_merge_use_first);
103 gst_tag_register (GST_TAG_CDDA_MUSICBRAINZ_DISCID_FULL, GST_TAG_FLAG_META,
104 G_TYPE_STRING, "musicbrainz-discid-full",
105 "Musicbrainz discid for metadata retrieval (full)",
106 gst_tag_merge_use_first);
108 /* photography tags */
109 gst_tag_register (GST_TAG_CAPTURING_SHUTTER_SPEED, GST_TAG_FLAG_META,
110 GST_TYPE_FRACTION, _("capturing shutter speed"),
111 _("Shutter speed used when capturing an image, in seconds"), NULL);
113 gst_tag_register (GST_TAG_CAPTURING_FOCAL_RATIO, GST_TAG_FLAG_META,
114 G_TYPE_DOUBLE, _("capturing focal ratio"),
115 _("Focal ratio (f-number) used when capturing the image"), NULL);
117 gst_tag_register (GST_TAG_CAPTURING_FOCAL_LENGTH, GST_TAG_FLAG_META,
118 G_TYPE_DOUBLE, _("capturing focal length"),
119 _("Focal length of the lens used capturing the image, in mm"), NULL);
121 gst_tag_register (GST_TAG_CAPTURING_DIGITAL_ZOOM_RATIO, GST_TAG_FLAG_META,
122 G_TYPE_DOUBLE, _("capturing digital zoom ratio"),
123 _("Digital zoom ratio used when capturing an image"), NULL);
125 gst_tag_register (GST_TAG_CAPTURING_ISO_SPEED, GST_TAG_FLAG_META,
126 G_TYPE_INT, _("capturing iso speed"),
127 _("The ISO speed used when capturing an image"), NULL);
129 gst_tag_register (GST_TAG_CAPTURING_EXPOSURE_PROGRAM, GST_TAG_FLAG_META,
130 G_TYPE_STRING, _("capturing exposure program"),
131 _("The exposure program used when capturing an image"), NULL);
133 gst_tag_register (GST_TAG_CAPTURING_EXPOSURE_MODE, GST_TAG_FLAG_META,
134 G_TYPE_STRING, _("capturing exposure mode"),
135 _("The exposure mode used when capturing an image"), NULL);
137 gst_tag_register (GST_TAG_CAPTURING_EXPOSURE_COMPENSATION, GST_TAG_FLAG_META,
138 G_TYPE_DOUBLE, _("capturing exposure compensation"),
139 _("The exposure compensation used when capturing an image"), NULL);
141 gst_tag_register (GST_TAG_CAPTURING_SCENE_CAPTURE_TYPE, GST_TAG_FLAG_META,
142 G_TYPE_STRING, _("capturing scene capture type"),
143 _("The scene capture mode used when capturing an image"), NULL);
145 gst_tag_register (GST_TAG_CAPTURING_GAIN_ADJUSTMENT, GST_TAG_FLAG_META,
146 G_TYPE_STRING, _("capturing gain adjustment"),
147 _("The overall gain adjustment applied on an image"), NULL);
149 gst_tag_register (GST_TAG_CAPTURING_WHITE_BALANCE, GST_TAG_FLAG_META,
150 G_TYPE_STRING, _("capturing white balance"),
151 _("The white balance mode set when capturing an image"), NULL);
153 gst_tag_register (GST_TAG_CAPTURING_CONTRAST, GST_TAG_FLAG_META,
154 G_TYPE_STRING, _("capturing contrast"),
155 _("The direction of contrast processing applied "
156 "when capturing an image"), NULL);
158 gst_tag_register (GST_TAG_CAPTURING_SATURATION, GST_TAG_FLAG_META,
159 G_TYPE_STRING, _("capturing saturation"),
160 _("The direction of saturation processing applied when "
161 "capturing an image"), NULL);
163 gst_tag_register (GST_TAG_CAPTURING_SHARPNESS, GST_TAG_FLAG_META,
164 G_TYPE_STRING, _("capturing sharpness"),
165 _("The direction of sharpness processing applied "
166 "when capturing an image"), NULL);
168 gst_tag_register (GST_TAG_CAPTURING_FLASH_FIRED, GST_TAG_FLAG_META,
169 G_TYPE_BOOLEAN, _("capturing flash fired"),
170 _("If the flash fired while capturing an image"), NULL);
172 gst_tag_register (GST_TAG_CAPTURING_FLASH_MODE, GST_TAG_FLAG_META,
173 G_TYPE_STRING, _("capturing flash mode"),
174 _("The selected flash mode while capturing an image"), NULL);
176 gst_tag_register (GST_TAG_CAPTURING_METERING_MODE, GST_TAG_FLAG_META,
177 G_TYPE_STRING, _("capturing metering mode"),
178 _("The metering mode used while determining exposure for capturing an"
181 gst_tag_register (GST_TAG_CAPTURING_SOURCE, GST_TAG_FLAG_META,
182 G_TYPE_STRING, _("capturing source"),
183 _("The source or type of device used for the capture"), NULL);
185 gst_tag_register (GST_TAG_IMAGE_HORIZONTAL_PPI, GST_TAG_FLAG_META,
186 G_TYPE_DOUBLE, _("image horizontal ppi"),
187 _("Media (image/video) intended horizontal pixel density in ppi"), NULL);
189 gst_tag_register (GST_TAG_IMAGE_VERTICAL_PPI, GST_TAG_FLAG_META,
190 G_TYPE_DOUBLE, _("image vertical ppi"),
191 _("Media (image/video) intended vertical pixel density in ppi"), NULL);
193 gst_tag_register (GST_TAG_ID3V2_FRAME, GST_TAG_FLAG_META,
194 GST_TYPE_BUFFER, _("ID3v2 frame"), _("unparsed id3v2 tag frame"),
195 gst_tag_merge_use_first);
200 /* FIXME 0.11: rename this to gst_tag_init() or gst_tag_register_tags() or
201 * even better: make tags auto-register themselves, either by defining them
202 * to a wrapper func that does the initing, or by adding tag factories so
203 * that the core can load+register tags automatically when needed. */
206 * gst_tag_register_musicbrainz_tags
208 * Registers additional musicbrainz-specific tags with the GStreamer tag
209 * system. Plugins and applications that use these tags should call this
210 * function before using them. Can be called multiple times.
213 gst_tag_register_musicbrainz_tags (void)
215 static GOnce mb_once = G_ONCE_INIT;
217 g_once (&mb_once, gst_tag_register_tags_internal, NULL);
221 register_tag_image_type_enum (GType * id)
223 static const GEnumValue image_types[] = {
224 {GST_TAG_IMAGE_TYPE_NONE, "GST_TAG_IMAGE_TYPE_NONE", "none"},
225 {GST_TAG_IMAGE_TYPE_UNDEFINED, "GST_TAG_IMAGE_TYPE_UNDEFINED", "undefined"},
226 {GST_TAG_IMAGE_TYPE_FRONT_COVER, "GST_TAG_IMAGE_TYPE_FRONT_COVER",
228 {GST_TAG_IMAGE_TYPE_BACK_COVER, "GST_TAG_IMAGE_TYPE_BACK_COVER",
230 {GST_TAG_IMAGE_TYPE_LEAFLET_PAGE, "GST_TAG_IMAGE_TYPE_LEAFLET_PAGE",
232 {GST_TAG_IMAGE_TYPE_MEDIUM, "GST_TAG_IMAGE_TYPE_MEDIUM", "medium"},
233 {GST_TAG_IMAGE_TYPE_LEAD_ARTIST, "GST_TAG_IMAGE_TYPE_LEAD_ARTIST",
235 {GST_TAG_IMAGE_TYPE_ARTIST, "GST_TAG_IMAGE_TYPE_ARTIST", "artist"},
236 {GST_TAG_IMAGE_TYPE_CONDUCTOR, "GST_TAG_IMAGE_TYPE_CONDUCTOR", "conductor"},
237 {GST_TAG_IMAGE_TYPE_BAND_ORCHESTRA, "GST_TAG_IMAGE_TYPE_BAND_ORCHESTRA",
239 {GST_TAG_IMAGE_TYPE_COMPOSER, "GST_TAG_IMAGE_TYPE_COMPOSER", "composer"},
240 {GST_TAG_IMAGE_TYPE_LYRICIST, "GST_TAG_IMAGE_TYPE_LYRICIST", "lyricist"},
241 {GST_TAG_IMAGE_TYPE_RECORDING_LOCATION,
242 "GST_TAG_IMAGE_TYPE_RECORDING_LOCATION",
243 "recording-location"},
244 {GST_TAG_IMAGE_TYPE_DURING_RECORDING, "GST_TAG_IMAGE_TYPE_DURING_RECORDING",
246 {GST_TAG_IMAGE_TYPE_DURING_PERFORMANCE,
247 "GST_TAG_IMAGE_TYPE_DURING_PERFORMANCE",
248 "during-performance"},
249 {GST_TAG_IMAGE_TYPE_VIDEO_CAPTURE, "GST_TAG_IMAGE_TYPE_VIDEO_CAPTURE",
251 {GST_TAG_IMAGE_TYPE_FISH, "GST_TAG_IMAGE_TYPE_FISH", "fish"},
252 {GST_TAG_IMAGE_TYPE_ILLUSTRATION, "GST_TAG_IMAGE_TYPE_ILLUSTRATION",
254 {GST_TAG_IMAGE_TYPE_BAND_ARTIST_LOGO, "GST_TAG_IMAGE_TYPE_BAND_ARTIST_LOGO",
256 {GST_TAG_IMAGE_TYPE_PUBLISHER_STUDIO_LOGO,
257 "GST_TAG_IMAGE_TYPE_PUBLISHER_STUDIO_LOGO",
258 "publisher-studio-logo"},
262 *id = g_enum_register_static ("GstTagImageType", image_types);
264 /* work around thread-safety issue with class creation in GLib */
265 g_type_class_ref (*id);
269 gst_tag_image_type_get_type (void)
273 static GOnce once = G_ONCE_INIT;
275 g_once (&once, (GThreadFunc) register_tag_image_type_enum, &id);
279 static inline gboolean
280 gst_tag_image_type_is_valid (GstTagImageType type)
286 klass = g_type_class_ref (gst_tag_image_type_get_type ());
287 res = (g_enum_get_value (klass, type) != NULL);
288 g_type_class_unref (klass);
294 * gst_tag_parse_extended_comment:
295 * @ext_comment: an extended comment string, see #GST_TAG_EXTENDED_COMMENT
296 * @key: return location for the comment description key, or NULL
297 * @lang: return location for the comment ISO-639 language code, or NULL
298 * @value: return location for the actual comment string, or NULL
299 * @fail_if_no_key: whether to fail if strings are not in key=value form
301 * Convenience function to parse a GST_TAG_EXTENDED_COMMENT string and
302 * separate it into its components.
304 * If successful, @key, @lang and/or @value will be set to newly allocated
305 * strings that you need to free with g_free() when done. @key and @lang
306 * may also be set to NULL by this function if there is no key or no language
307 * code in the extended comment string.
309 * Returns: TRUE if the string could be parsed, otherwise FALSE
314 gst_tag_parse_extended_comment (const gchar * ext_comment, gchar ** key,
315 gchar ** lang, gchar ** value, gboolean fail_if_no_key)
317 const gchar *div, *bop, *bcl;
319 g_return_val_if_fail (ext_comment != NULL, FALSE);
320 g_return_val_if_fail (g_utf8_validate (ext_comment, -1, NULL), FALSE);
327 div = strchr (ext_comment, '=');
328 bop = strchr (ext_comment, '[');
329 bcl = strchr (ext_comment, ']');
335 *value = g_strdup (ext_comment);
339 if (bop != NULL && bop < div) {
340 if (bcl < bop || bcl > div)
343 *key = g_strndup (ext_comment, bop - ext_comment);
345 *lang = g_strndup (bop + 1, bcl - bop - 1);
348 *key = g_strndup (ext_comment, div - ext_comment);
352 *value = g_strdup (div + 1);
358 * gst_tag_freeform_string_to_utf8:
360 * @size: length of string data, or -1 if the string is NUL-terminated
361 * @env_vars: a NULL-terminated string array of environment variable names,
364 * Convenience function to read a string with unknown character encoding. If
365 * the string is already in UTF-8 encoding, it will be returned right away.
366 * If not it tries to detect byte-order-mark for UTF-16/32 cases and use that.
367 * Otherwise, the environment will be searched for a number of environment
368 * variables (whose names are specified in the NULL-terminated string array
369 * @env_vars) containing a list of character encodings to try/use. If none
370 * are specified, the current locale will be tried. If that also doesn't work,
371 * WINDOWS-1252/ISO-8859-1 is assumed (which will almost always succeed).
373 * Returns: a newly-allocated string in UTF-8 encoding, or NULL
378 gst_tag_freeform_string_to_utf8 (const gchar * data, gint size,
379 const gchar ** env_vars)
381 const gchar *cur_loc = NULL;
387 g_return_val_if_fail (data != NULL, NULL);
390 size = strlen (data);
392 /* chop off trailing string terminators to make sure utf8_validate doesn't
393 * get to see them (since that would make the utf8 check fail) */
394 while (size > 0 && data[size - 1] == '\0')
397 /* Should we try the charsets specified
398 * via environment variables FIRST ? */
399 if (g_utf8_validate (data, size, NULL)) {
400 utf8 = g_strndup (data, size);
401 GST_LOG ("String '%s' is valid UTF-8 already", utf8);
405 /* check for and use byte-order-mark for UTF-16/32 cases */
407 const gchar *c = NULL;
412 ssize = GST_ROUND_DOWN_4 (size - 4);
413 switch (GST_READ_UINT32_BE (data)) {
426 ssize = GST_ROUND_DOWN_2 (size - 2);
427 switch (GST_READ_UINT16_BE (data)) {
439 GST_LOG ("Trying to convert freeform string to UTF-8 from '%s'", c);
441 g_convert (data + prefix, ssize, "UTF-8", c, &bytes_read, NULL,
443 if (bytes_read == ssize)
451 while (env_vars && *env_vars != NULL) {
452 const gchar *env = NULL;
454 /* Try charsets specified via the environment */
455 env = g_getenv (*env_vars);
456 if (env != NULL && *env != '\0') {
459 csets = g_strsplit (env, G_SEARCHPATH_SEPARATOR_S, -1);
461 for (c = csets; c && *c; ++c) {
462 GST_LOG ("Trying to convert freeform string to UTF-8 from '%s'", *c);
464 g_convert (data, size, "UTF-8", *c, &bytes_read, NULL, NULL))) {
465 if (bytes_read == size) {
479 /* Try current locale (if not UTF-8) */
480 if (!g_get_charset (&cur_loc)) {
481 GST_LOG ("Trying to convert freeform string using locale ('%s')", cur_loc);
482 if ((utf8 = g_locale_to_utf8 (data, size, &bytes_read, NULL, NULL))) {
483 if (bytes_read == size) {
491 /* Try Windows-1252 (which is a superset of ISO 8859-1 that uses a control
492 * character range in ISO 8859-1 for more printable characters) */
496 GST_LOG ("Trying to convert freeform string using Windows-1252/ISO-8859-1 "
498 utf8 = g_convert (data, size, "UTF-8", "WINDOWS-1252", &bytes_read, NULL,
501 /* fallback in case iconv implementation doesn't support windows-1252
503 if (err->code == G_CONVERT_ERROR_NO_CONVERSION) {
505 utf8 = g_convert (data, size, "UTF-8", "ISO-8859-1", &bytes_read,
511 if (utf8 != NULL && bytes_read == size)
521 if (utf8 && utf8[0] != '\0') {
522 GST_LOG ("Returning '%s'", utf8);
531 * gst_tag_image_data_to_image_buffer:
532 * @image_data: the (encoded) image
533 * @image_data_len: the length of the encoded image data at @image_data
534 * @image_type: type of the image, or #GST_TAG_IMAGE_TYPE_UNDEFINED. Pass
535 * #GST_TAG_IMAGE_TYPE_NONE if no image type should be set at all (e.g.
536 * for preview images)
538 * Helper function for tag-reading plugins to create a #GstBuffer suitable to
539 * add to a #GstTagList as an image tag (such as #GST_TAG_IMAGE or
540 * #GST_TAG_PREVIEW_IMAGE) from the encoded image data and an (optional) image
543 * Background: cover art and other images in tags are usually stored as a
544 * blob of binary image data, often accompanied by a MIME type or some other
545 * content type string (e.g. 'png', 'jpeg', 'jpg'). Sometimes there is also an
546 * 'image type' to indicate what kind of image this is (e.g. front cover,
547 * back cover, artist, etc.). The image data may also be an URI to the image
548 * rather than the image itself.
550 * In GStreamer, image tags are #GstBuffer<!-- -->s containing the raw image
551 * data, with the buffer caps describing the content type of the image
552 * (e.g. image/jpeg, image/png, text/uri-list). The buffer caps may contain
553 * an additional 'image-type' field of #GST_TYPE_TAG_IMAGE_TYPE to describe
554 * the type of image (front cover, back cover etc.). #GST_TAG_PREVIEW_IMAGE
555 * tags should not carry an image type, their type is already indicated via
556 * the special tag name.
558 * This function will do various checks and typefind the encoded image
559 * data (we can't trust the declared mime type).
561 * Returns: a newly-allocated image buffer for use in tag lists, or NULL
566 gst_tag_image_data_to_image_buffer (const guint8 * image_data,
567 guint image_data_len, GstTagImageType image_type)
575 g_return_val_if_fail (image_data != NULL, NULL);
576 g_return_val_if_fail (image_data_len > 0, NULL);
577 g_return_val_if_fail (gst_tag_image_type_is_valid (image_type), NULL);
579 GST_DEBUG ("image data len: %u bytes", image_data_len);
581 /* allocate space for a NUL terminator for an uri too */
582 image = gst_buffer_try_new_and_alloc (image_data_len + 1);
584 GST_WARNING ("failed to allocate buffer of %d for image", image_data_len);
588 memcpy (GST_BUFFER_DATA (image), image_data, image_data_len);
589 GST_BUFFER_DATA (image)[image_data_len] = '\0';
591 /* Find GStreamer media type, can't trust declared type */
592 caps = gst_type_find_helper_for_buffer (NULL, image, NULL);
597 GST_DEBUG ("Found GStreamer media type: %" GST_PTR_FORMAT, caps);
599 /* sanity check: make sure typefound/declared caps are either URI or image */
600 name = gst_structure_get_name (gst_caps_get_structure (caps, 0));
602 if (!g_str_has_prefix (name, "image/") &&
603 !g_str_has_prefix (name, "video/") &&
604 !g_str_equal (name, "text/uri-list")) {
605 GST_DEBUG ("Unexpected image type '%s', ignoring image frame", name);
609 /* Decrease size by 1 if we don't have an URI list
610 * to keep the original size of the image
612 if (!g_str_equal (name, "text/uri-list"))
613 GST_BUFFER_SIZE (image) = image_data_len;
615 if (image_type != GST_TAG_IMAGE_TYPE_NONE) {
616 GST_LOG ("Setting image type: %d", image_type);
617 caps = gst_caps_make_writable (caps);
618 gst_caps_set_simple (caps, "image-type", GST_TYPE_TAG_IMAGE_TYPE,
622 gst_buffer_set_caps (image, caps);
623 gst_caps_unref (caps);
629 GST_DEBUG ("Could not determine GStreamer media type, ignoring image");
635 gst_buffer_unref (image);
637 gst_caps_unref (caps);