/* GStreamer non-core tag registration and tag utility functions
* Copyright (C) 2005 Ross Burton <ross@burtonini.com>
* Copyright (C) 2006-2008 Tim-Philipp Müller <tim centricular net>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/gst-i18n-plugin.h>
#include <gst/base/gsttypefindhelper.h>
#include <gst/gst.h>
#include "tag.h"
#include "id3v2.h"
#include <string.h>
/**
* SECTION:gsttag
* @title: Tags
* @short_description: additional tag definitions for plugins and applications
* @see_also: #GstTagList
*
* Contains additional standardized GStreamer tag definitions for plugins
* and applications, and functions to register them with the GStreamer
* tag system.
*
*/
#ifndef GST_DISABLE_GST_DEBUG
#define GST_CAT_DEFAULT gst_tag_ensure_debug_category()
static GstDebugCategory *
gst_tag_ensure_debug_category (void)
{
static gsize cat_gonce = 0;
if (g_once_init_enter (&cat_gonce)) {
GstDebugCategory *cat = NULL;
GST_DEBUG_CATEGORY_INIT (cat, "tag-tags", 0, "GstTag helper functions");
g_once_init_leave (&cat_gonce, (gsize) cat);
}
return (GstDebugCategory *) cat_gonce;
}
#endif /* GST_DISABLE_GST_DEBUG */
static gpointer
gst_tag_register_tags_internal (gpointer unused)
{
#ifdef ENABLE_NLS
GST_DEBUG ("binding text domain %s to locale dir %s", GETTEXT_PACKAGE,
LOCALEDIR);
bindtextdomain (GETTEXT_PACKAGE, LOCALEDIR);
bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
#endif
/* musicbrainz tags */
gst_tag_register_static (GST_TAG_MUSICBRAINZ_TRACKID, GST_TAG_FLAG_META,
G_TYPE_STRING, _("track ID"), _("MusicBrainz track ID"), NULL);
gst_tag_register_static (GST_TAG_MUSICBRAINZ_ARTISTID, GST_TAG_FLAG_META,
G_TYPE_STRING, _("artist ID"), _("MusicBrainz artist ID"), NULL);
gst_tag_register_static (GST_TAG_MUSICBRAINZ_ALBUMID, GST_TAG_FLAG_META,
G_TYPE_STRING, _("album ID"), _("MusicBrainz album ID"), NULL);
gst_tag_register_static (GST_TAG_MUSICBRAINZ_ALBUMARTISTID, GST_TAG_FLAG_META,
G_TYPE_STRING,
_("album artist ID"), _("MusicBrainz album artist ID"), NULL);
gst_tag_register_static (GST_TAG_MUSICBRAINZ_TRMID, GST_TAG_FLAG_META,
G_TYPE_STRING, _("track TRM ID"), _("MusicBrainz TRM ID"), NULL);
/* CDDA tags */
gst_tag_register_static (GST_TAG_CDDA_CDDB_DISCID, GST_TAG_FLAG_META,
G_TYPE_STRING, "discid", "CDDB discid for metadata retrieval",
gst_tag_merge_use_first);
gst_tag_register_static (GST_TAG_CDDA_CDDB_DISCID_FULL, GST_TAG_FLAG_META,
G_TYPE_STRING, "discid full",
"CDDB discid for metadata retrieval (full)", gst_tag_merge_use_first);
gst_tag_register_static (GST_TAG_CDDA_MUSICBRAINZ_DISCID, GST_TAG_FLAG_META,
G_TYPE_STRING, "musicbrainz-discid",
"Musicbrainz discid for metadata retrieval", gst_tag_merge_use_first);
gst_tag_register_static (GST_TAG_CDDA_MUSICBRAINZ_DISCID_FULL,
GST_TAG_FLAG_META, G_TYPE_STRING, "musicbrainz-discid-full",
"Musicbrainz discid for metadata retrieval (full)",
gst_tag_merge_use_first);
/* photography tags */
gst_tag_register_static (GST_TAG_CAPTURING_SHUTTER_SPEED, GST_TAG_FLAG_META,
GST_TYPE_FRACTION, _("capturing shutter speed"),
_("Shutter speed used when capturing an image, in seconds"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_FOCAL_RATIO, GST_TAG_FLAG_META,
G_TYPE_DOUBLE, _("capturing focal ratio"),
_("Focal ratio (f-number) used when capturing the image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_FOCAL_LENGTH, GST_TAG_FLAG_META,
G_TYPE_DOUBLE, _("capturing focal length"),
_("Focal length of the lens used capturing the image, in mm"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_FOCAL_LENGTH_35_MM,
GST_TAG_FLAG_META, G_TYPE_DOUBLE,
_("capturing 35 mm equivalent focal length"),
_("35 mm equivalent focal length of the lens used capturing the image, "
"in mm"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_DIGITAL_ZOOM_RATIO,
GST_TAG_FLAG_META, G_TYPE_DOUBLE, _("capturing digital zoom ratio"),
_("Digital zoom ratio used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_ISO_SPEED, GST_TAG_FLAG_META,
G_TYPE_INT, _("capturing iso speed"),
_("The ISO speed used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_EXPOSURE_PROGRAM,
GST_TAG_FLAG_META, G_TYPE_STRING, _("capturing exposure program"),
_("The exposure program used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_EXPOSURE_MODE, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing exposure mode"),
_("The exposure mode used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_EXPOSURE_COMPENSATION,
GST_TAG_FLAG_META, G_TYPE_DOUBLE, _("capturing exposure compensation"),
_("The exposure compensation used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_SCENE_CAPTURE_TYPE,
GST_TAG_FLAG_META, G_TYPE_STRING, _("capturing scene capture type"),
_("The scene capture mode used when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_GAIN_ADJUSTMENT, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing gain adjustment"),
_("The overall gain adjustment applied on an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_WHITE_BALANCE, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing white balance"),
_("The white balance mode set when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_CONTRAST, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing contrast"),
_("The direction of contrast processing applied "
"when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_SATURATION, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing saturation"),
_("The direction of saturation processing applied when "
"capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_SHARPNESS, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing sharpness"),
_("The direction of sharpness processing applied "
"when capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_FLASH_FIRED, GST_TAG_FLAG_META,
G_TYPE_BOOLEAN, _("capturing flash fired"),
_("If the flash fired while capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_FLASH_MODE, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing flash mode"),
_("The selected flash mode while capturing an image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_METERING_MODE, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing metering mode"),
_("The metering mode used while determining exposure for capturing an"
" image"), NULL);
gst_tag_register_static (GST_TAG_CAPTURING_SOURCE, GST_TAG_FLAG_META,
G_TYPE_STRING, _("capturing source"),
_("The source or type of device used for the capture"), NULL);
gst_tag_register_static (GST_TAG_IMAGE_HORIZONTAL_PPI, GST_TAG_FLAG_META,
G_TYPE_DOUBLE, _("image horizontal ppi"),
_("Media (image/video) intended horizontal pixel density in ppi"), NULL);
gst_tag_register_static (GST_TAG_IMAGE_VERTICAL_PPI, GST_TAG_FLAG_META,
G_TYPE_DOUBLE, _("image vertical ppi"),
_("Media (image/video) intended vertical pixel density in ppi"), NULL);
gst_tag_register_static (GST_TAG_ID3V2_FRAME, GST_TAG_FLAG_META,
GST_TYPE_SAMPLE, _("ID3v2 frame"), _("unparsed id3v2 tag frame"),
gst_tag_merge_use_first);
gst_tag_register_static (GST_TAG_MUSICAL_KEY, GST_TAG_FLAG_META,
G_TYPE_STRING, _("musical-key"), _("Initial key in which the "
"sound starts"), gst_tag_merge_use_first);
return NULL;
}
/* FIXME 0.11: rename this to gst_tag_init() or gst_tag_register_tags() or
* even better: make tags auto-register themselves, either by defining them
* to a wrapper func that does the initing, or by adding tag factories so
* that the core can load+register tags automatically when needed. */
/**
* gst_tag_register_musicbrainz_tags:
*
* Registers additional musicbrainz-specific tags with the GStreamer tag
* system. Plugins and applications that use these tags should call this
* function before using them. Can be called multiple times.
*/
void
gst_tag_register_musicbrainz_tags (void)
{
static GOnce mb_once = G_ONCE_INIT;
g_once (&mb_once, gst_tag_register_tags_internal, NULL);
}
static inline gboolean
gst_tag_image_type_is_valid (GstTagImageType type)
{
GEnumClass *klass;
gboolean res;
klass = g_type_class_ref (gst_tag_image_type_get_type ());
res = (g_enum_get_value (klass, type) != NULL);
g_type_class_unref (klass);
return res;
}
/**
* gst_tag_parse_extended_comment:
* @ext_comment: an extended comment string, see #GST_TAG_EXTENDED_COMMENT
* @key: (out) (nullable):
* return location for the comment description key, or NULL
* @lang: (out) (nullable):
* return location for the comment ISO-639 language code, or NULL
* @value: (out): return location for the actual comment string, or NULL
* @fail_if_no_key: whether to fail if strings are not in key=value form
*
* Convenience function to parse a GST_TAG_EXTENDED_COMMENT string and
* separate it into its components.
*
* If successful, @key, @lang and/or @value will be set to newly allocated
* strings that you need to free with g_free() when done. @key and @lang
* may also be set to NULL by this function if there is no key or no language
* code in the extended comment string.
*
* Returns: TRUE if the string could be parsed, otherwise FALSE
*/
gboolean
gst_tag_parse_extended_comment (const gchar * ext_comment, gchar ** key,
gchar ** lang, gchar ** value, gboolean fail_if_no_key)
{
const gchar *div, *bop, *bcl;
g_return_val_if_fail (ext_comment != NULL, FALSE);
g_return_val_if_fail (g_utf8_validate (ext_comment, -1, NULL), FALSE);
if (key)
*key = NULL;
if (lang)
*lang = NULL;
div = strchr (ext_comment, '=');
bop = strchr (ext_comment, '[');
bcl = strchr (ext_comment, ']');
if (div == NULL) {
if (fail_if_no_key)
return FALSE;
if (value)
*value = g_strdup (ext_comment);
return TRUE;
}
if (bop != NULL && bop < div) {
if (bcl < bop || bcl > div)
return FALSE;
if (key)
*key = g_strndup (ext_comment, bop - ext_comment);
if (lang)
*lang = g_strndup (bop + 1, bcl - bop - 1);
} else {
if (key)
*key = g_strndup (ext_comment, div - ext_comment);
}
if (value)
*value = g_strdup (div + 1);
return TRUE;
}
/**
* gst_tag_freeform_string_to_utf8:
* @data: (array length=size) (element-type gchar): string data
* @size: length of string data, or -1 if the string is NUL-terminated
* @env_vars: (array zero-terminated=1)
* a NULL-terminated string array of environment variable names, or NULL
*
* Convenience function to read a string with unknown character encoding. If
* the string is already in UTF-8 encoding, it will be returned right away.
* If not it tries to detect byte-order-mark for UTF-16/32 cases and use that.
* Otherwise, the environment will be searched for a number of environment
* variables (whose names are specified in the NULL-terminated string array
* @env_vars) containing a list of character encodings to try/use. If none
* are specified, the current locale will be tried. If that also doesn't work,
* WINDOWS-1252/ISO-8859-1 is assumed (which will almost always succeed).
*
* Returns: a newly-allocated string in UTF-8 encoding, or NULL
*/
gchar *
gst_tag_freeform_string_to_utf8 (const gchar * data, gint size,
const gchar ** env_vars)
{
const gchar *cur_loc = NULL;
gsize bytes_read;
gchar *utf8 = NULL;
g_return_val_if_fail (data != NULL, NULL);
if (size < 0)
size = strlen (data);
/* chop off trailing string terminators to make sure utf8_validate doesn't
* get to see them (since that would make the utf8 check fail) */
while (size > 0 && data[size - 1] == '\0')
--size;
/* Should we try the charsets specified
* via environment variables FIRST ? */
if (g_utf8_validate (data, size, NULL)) {
utf8 = g_strndup (data, size);
GST_LOG ("String '%s' is valid UTF-8 already", utf8);
goto beach;
}
/* check for and use byte-order-mark for UTF-16/32 cases */
if (size >= 2) {
const gchar *c = NULL;
gint prefix, ssize;
if (size >= 4) {
prefix = 4;
ssize = GST_ROUND_DOWN_4 (size - 4);
switch (GST_READ_UINT32_BE (data)) {
case 0x0000FEFF:
c = "UTF-32BE";
break;
case 0xFFFE0000:
c = "UTF-32LE";
break;
default:
break;
}
}
if (!c) {
prefix = 2;
ssize = GST_ROUND_DOWN_2 (size - 2);
switch (GST_READ_UINT16_BE (data)) {
case 0xFEFF:
c = "UTF-16BE";
break;
case 0xFFFE:
c = "UTF-16LE";
break;
default:
break;
}
}
if (c) {
GST_LOG ("Trying to convert freeform string to UTF-8 from '%s'", c);
if ((utf8 =
g_convert (data + prefix, ssize, "UTF-8", c, &bytes_read, NULL,
NULL))) {
if (bytes_read == ssize)
goto beach;
g_free (utf8);
utf8 = NULL;
}
}
}
while (env_vars && *env_vars != NULL) {
const gchar *env = NULL;
/* Try charsets specified via the environment */
env = g_getenv (*env_vars);
if (env != NULL && *env != '\0') {
gchar **c, **csets;
csets = g_strsplit (env, G_SEARCHPATH_SEPARATOR_S, -1);
for (c = csets; c && *c; ++c) {
GST_LOG ("Trying to convert freeform string to UTF-8 from '%s'", *c);
if ((utf8 =
g_convert (data, size, "UTF-8", *c, &bytes_read, NULL, NULL))) {
if (bytes_read == size) {
g_strfreev (csets);
goto beach;
}
g_free (utf8);
utf8 = NULL;
}
}
g_strfreev (csets);
}
++env_vars;
}
/* Try current locale (if not UTF-8) */
if (!g_get_charset (&cur_loc)) {
GST_LOG ("Trying to convert freeform string using locale ('%s')", cur_loc);
if ((utf8 = g_locale_to_utf8 (data, size, &bytes_read, NULL, NULL))) {
if (bytes_read == size) {
goto beach;
}
g_free (utf8);
utf8 = NULL;
}
}
/* Try Windows-1252 (which is a superset of ISO 8859-1 that uses a control
* character range in ISO 8859-1 for more printable characters) */
{
GError *err = NULL;
GST_LOG ("Trying to convert freeform string using Windows-1252/ISO-8859-1 "
"fallback");
utf8 = g_convert (data, size, "UTF-8", "WINDOWS-1252", &bytes_read, NULL,
&err);
if (err != NULL) {
/* fallback in case iconv implementation doesn't support windows-1252
* for some reason */
if (err->code == G_CONVERT_ERROR_NO_CONVERSION) {
g_free (utf8);
utf8 = g_convert (data, size, "UTF-8", "ISO-8859-1", &bytes_read,
NULL, NULL);
}
g_error_free (err);
}
if (utf8 != NULL && bytes_read == size)
goto beach;
}
g_free (utf8);
return NULL;
beach:
g_strchomp (utf8);
if (utf8 && utf8[0] != '\0') {
GST_LOG ("Returning '%s'", utf8);
return utf8;
}
g_free (utf8);
return NULL;
}
/**
* gst_tag_image_data_to_image_sample:
* @image_data: (array length=image_data_len): the (encoded) image
* @image_data_len: the length of the encoded image data at @image_data
* @image_type: type of the image, or #GST_TAG_IMAGE_TYPE_UNDEFINED. Pass
* #GST_TAG_IMAGE_TYPE_NONE if no image type should be set at all (e.g.
* for preview images)
*
* Helper function for tag-reading plugins to create a #GstSample suitable to
* add to a #GstTagList as an image tag (such as #GST_TAG_IMAGE or
* #GST_TAG_PREVIEW_IMAGE) from the encoded image data and an (optional) image
* type.
*
* Background: cover art and other images in tags are usually stored as a
* blob of binary image data, often accompanied by a MIME type or some other
* content type string (e.g. 'png', 'jpeg', 'jpg'). Sometimes there is also an
* 'image type' to indicate what kind of image this is (e.g. front cover,
* back cover, artist, etc.). The image data may also be an URI to the image
* rather than the image itself.
*
* In GStreamer, image tags are #GstSample<!-- -->s containing the raw image
* data, with the sample caps describing the content type of the image
* (e.g. image/jpeg, image/png, text/uri-list). The sample info may contain
* an additional 'image-type' field of #GST_TYPE_TAG_IMAGE_TYPE to describe
* the type of image (front cover, back cover etc.). #GST_TAG_PREVIEW_IMAGE
* tags should not carry an image type, their type is already indicated via
* the special tag name.
*
* This function will do various checks and typefind the encoded image
* data (we can't trust the declared mime type).
*
* Returns: a newly-allocated image sample for use in tag lists, or NULL
*/
GstSample *
gst_tag_image_data_to_image_sample (const guint8 * image_data,
guint image_data_len, GstTagImageType image_type)
{
const gchar *name;
GstBuffer *image;
GstSample *sample;
GstCaps *caps;
GstMapInfo info;
GstStructure *image_info = NULL;
g_return_val_if_fail (image_data != NULL, NULL);
g_return_val_if_fail (image_data_len > 0, NULL);
g_return_val_if_fail (gst_tag_image_type_is_valid (image_type), NULL);
GST_DEBUG ("image data len: %u bytes", image_data_len);
/* allocate space for a NUL terminator for an uri too */
image = gst_buffer_new_and_alloc (image_data_len + 1);
if (image == NULL)
goto alloc_failed;
gst_buffer_map (image, &info, GST_MAP_WRITE);
memcpy (info.data, image_data, image_data_len);
info.data[image_data_len] = '\0';
gst_buffer_unmap (image, &info);
/* Find GStreamer media type, can't trust declared type */
caps = gst_type_find_helper_for_buffer (NULL, image, NULL);
if (caps == NULL)
goto no_type;
GST_DEBUG ("Found GStreamer media type: %" GST_PTR_FORMAT, caps);
/* sanity check: make sure typefound/declared caps are either URI or image */
name = gst_structure_get_name (gst_caps_get_structure (caps, 0));
if (!g_str_has_prefix (name, "image/") &&
!g_str_has_prefix (name, "video/") &&
!g_str_equal (name, "text/uri-list")) {
GST_DEBUG ("Unexpected image type '%s', ignoring image frame", name);
goto error;
}
/* Decrease size by 1 if we don't have an URI list
* to keep the original size of the image
*/
if (!g_str_equal (name, "text/uri-list"))
gst_buffer_set_size (image, image_data_len);
if (image_type != GST_TAG_IMAGE_TYPE_NONE) {
GST_LOG ("Setting image type: %d", image_type);
image_info = gst_structure_new ("GstTagImageInfo",
"image-type", GST_TYPE_TAG_IMAGE_TYPE, image_type, NULL);
}
sample = gst_sample_new (image, caps, NULL, image_info);
gst_buffer_unref (image);
gst_caps_unref (caps);
return sample;
/* ERRORS */
no_type:
{
GST_DEBUG ("Could not determine GStreamer media type, ignoring image");
/* fall through */
}
error:
{
if (image)
gst_buffer_unref (image);
if (caps)
gst_caps_unref (caps);
return NULL;
}
alloc_failed:
{
GST_WARNING ("failed to allocate buffer of %d for image", image_data_len);
gst_buffer_unref (image);
return NULL;
}
}