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GStreamer 0.10 Core Reference Manual | ![]() |
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Top | Description |
#include <gst/gst.h> GstTagList; enum GstTagMergeMode; enum GstTagFlag; void (*GstTagForeachFunc) (const GstTagList *list
,const gchar *tag
,gpointer user_data
); void (*GstTagMergeFunc) (GValue *dest
,const GValue *src
); #define GST_TAG_TITLE #define GST_TAG_TITLE_SORTNAME #define GST_TAG_ARTIST #define GST_TAG_ARTIST_SORTNAME #define GST_TAG_ALBUM #define GST_TAG_ALBUM_SORTNAME #define GST_TAG_ALBUM_ARTIST #define GST_TAG_ALBUM_ARTIST_SORTNAME #define GST_TAG_DATE #define GST_TAG_GENRE #define GST_TAG_COMMENT #define GST_TAG_EXTENDED_COMMENT #define GST_TAG_TRACK_NUMBER #define GST_TAG_TRACK_COUNT #define GST_TAG_ALBUM_VOLUME_NUMBER #define GST_TAG_ALBUM_VOLUME_COUNT #define GST_TAG_LOCATION #define GST_TAG_HOMEPAGE #define GST_TAG_DESCRIPTION #define GST_TAG_VERSION #define GST_TAG_ISRC #define GST_TAG_ORGANIZATION #define GST_TAG_COPYRIGHT #define GST_TAG_COPYRIGHT_URI #define GST_TAG_COMPOSER #define GST_TAG_CONTACT #define GST_TAG_LICENSE #define GST_TAG_LICENSE_URI #define GST_TAG_PERFORMER #define GST_TAG_DURATION #define GST_TAG_CODEC #define GST_TAG_VIDEO_CODEC #define GST_TAG_AUDIO_CODEC #define GST_TAG_SUBTITLE_CODEC #define GST_TAG_CONTAINER_FORMAT #define GST_TAG_BITRATE #define GST_TAG_NOMINAL_BITRATE #define GST_TAG_MINIMUM_BITRATE #define GST_TAG_MAXIMUM_BITRATE #define GST_TAG_SERIAL #define GST_TAG_ENCODER #define GST_TAG_ENCODER_VERSION #define GST_TAG_TRACK_GAIN #define GST_TAG_TRACK_PEAK #define GST_TAG_ALBUM_GAIN #define GST_TAG_ALBUM_PEAK #define GST_TAG_REFERENCE_LEVEL #define GST_TAG_LANGUAGE_CODE #define GST_TAG_IMAGE #define GST_TAG_PREVIEW_IMAGE #define GST_TAG_ATTACHMENT #define GST_TAG_BEATS_PER_MINUTE #define GST_TAG_KEYWORDS #define GST_TAG_GEO_LOCATION_NAME #define GST_TAG_GEO_LOCATION_LATITUDE #define GST_TAG_GEO_LOCATION_LONGITUDE #define GST_TAG_GEO_LOCATION_ELEVATION #define GST_TAG_GEO_LOCATION_CITY #define GST_TAG_GEO_LOCATION_COUNTRY #define GST_TAG_GEO_LOCATION_SUBLOCATION #define GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION #define GST_TAG_GEO_LOCATION_MOVEMENT_SPEED #define GST_TAG_GEO_LOCATION_CAPTURE_DIRECTION #define GST_TAG_SHOW_NAME #define GST_TAG_SHOW_SORTNAME #define GST_TAG_SHOW_EPISODE_NUMBER #define GST_TAG_SHOW_SEASON_NUMBER #define GST_TAG_LYRICS #define GST_TAG_COMPOSER_SORTNAME #define GST_TAG_GROUPING #define GST_TAG_USER_RATING #define GST_TAG_DEVICE_MANUFACTURER #define GST_TAG_DEVICE_MODEL #define GST_TAG_IMAGE_ORIENTATION void gst_tag_register (const gchar *name
,GstTagFlag flag
,GType type
,const gchar *nick
,const gchar *blurb
,GstTagMergeFunc func
); void gst_tag_merge_use_first (GValue *dest
,const GValue *src
); void gst_tag_merge_strings_with_comma (GValue *dest
,const GValue *src
); gboolean gst_tag_exists (const gchar *tag
); GType gst_tag_get_type (const gchar *tag
); const gchar * gst_tag_get_nick (const gchar *tag
); const gchar * gst_tag_get_description (const gchar *tag
); GstTagFlag gst_tag_get_flag (const gchar *tag
); gboolean gst_tag_is_fixed (const gchar *tag
); GstTagList * gst_tag_list_new (void
); GstTagList * gst_tag_list_new_full (const gchar *tag
,...
); GstTagList * gst_tag_list_new_full_valist (va_list var_args
); gboolean gst_is_tag_list (gconstpointer p
); gboolean gst_tag_list_is_empty (const GstTagList *list
); GstTagList * gst_tag_list_copy (const GstTagList *list
); void gst_tag_list_insert (GstTagList *into
,const GstTagList *from
,GstTagMergeMode mode
); GstTagList * gst_tag_list_merge (const GstTagList *list1
,const GstTagList *list2
,GstTagMergeMode mode
); void gst_tag_list_free (GstTagList *list
); guint gst_tag_list_get_tag_size (const GstTagList *list
,const gchar *tag
); void gst_tag_list_add (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,...
); void gst_tag_list_add_value (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,const GValue *value
); void gst_tag_list_add_values (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,...
); void gst_tag_list_add_valist (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,va_list var_args
); void gst_tag_list_add_valist_values (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,va_list var_args
); void gst_tag_list_remove_tag (GstTagList *list
,const gchar *tag
); void gst_tag_list_foreach (const GstTagList *list
,GstTagForeachFunc func
,gpointer user_data
); const GValue * gst_tag_list_get_value_index (const GstTagList *list
,const gchar *tag
,guint index
); gboolean gst_tag_list_copy_value (GValue *dest
,const GstTagList *list
,const gchar *tag
); gboolean gst_tag_list_get_char (const GstTagList *list
,const gchar *tag
,gchar *value
); gboolean gst_tag_list_get_char_index (const GstTagList *list
,const gchar *tag
,guint index
,gchar *value
); gboolean gst_tag_list_get_uchar (const GstTagList *list
,const gchar *tag
,guchar *value
); gboolean gst_tag_list_get_uchar_index (const GstTagList *list
,const gchar *tag
,guint index
,guchar *value
); gboolean gst_tag_list_get_boolean (const GstTagList *list
,const gchar *tag
,gboolean *value
); gboolean gst_tag_list_get_boolean_index (const GstTagList *list
,const gchar *tag
,guint index
,gboolean *value
); gboolean gst_tag_list_get_int (const GstTagList *list
,const gchar *tag
,gint *value
); gboolean gst_tag_list_get_int_index (const GstTagList *list
,const gchar *tag
,guint index
,gint *value
); gboolean gst_tag_list_get_uint (const GstTagList *list
,const gchar *tag
,guint *value
); gboolean gst_tag_list_get_uint_index (const GstTagList *list
,const gchar *tag
,guint index
,guint *value
); gboolean gst_tag_list_get_long (const GstTagList *list
,const gchar *tag
,glong *value
); gboolean gst_tag_list_get_long_index (const GstTagList *list
,const gchar *tag
,guint index
,glong *value
); gboolean gst_tag_list_get_ulong (const GstTagList *list
,const gchar *tag
,gulong *value
); gboolean gst_tag_list_get_ulong_index (const GstTagList *list
,const gchar *tag
,guint index
,gulong *value
); gboolean gst_tag_list_get_int64 (const GstTagList *list
,const gchar *tag
,gint64 *value
); gboolean gst_tag_list_get_int64_index (const GstTagList *list
,const gchar *tag
,guint index
,gint64 *value
); gboolean gst_tag_list_get_uint64 (const GstTagList *list
,const gchar *tag
,guint64 *value
); gboolean gst_tag_list_get_uint64_index (const GstTagList *list
,const gchar *tag
,guint index
,guint64 *value
); gboolean gst_tag_list_get_float (const GstTagList *list
,const gchar *tag
,gfloat *value
); gboolean gst_tag_list_get_float_index (const GstTagList *list
,const gchar *tag
,guint index
,gfloat *value
); gboolean gst_tag_list_get_double (const GstTagList *list
,const gchar *tag
,gdouble *value
); gboolean gst_tag_list_get_double_index (const GstTagList *list
,const gchar *tag
,guint index
,gdouble *value
); gboolean gst_tag_list_get_string (const GstTagList *list
,const gchar *tag
,gchar **value
); gboolean gst_tag_list_get_string_index (const GstTagList *list
,const gchar *tag
,guint index
,gchar **value
); gboolean gst_tag_list_peek_string_index (const GstTagList *list
,const gchar *tag
,guint index
,const gchar **value
); gboolean gst_tag_list_get_pointer (const GstTagList *list
,const gchar *tag
,gpointer *value
); gboolean gst_tag_list_get_pointer_index (const GstTagList *list
,const gchar *tag
,guint index
,gpointer *value
); gboolean gst_tag_list_get_date (const GstTagList *list
,const gchar *tag
,GDate **value
); gboolean gst_tag_list_get_date_index (const GstTagList *list
,const gchar *tag
,guint index
,GDate **value
); gboolean gst_tag_list_get_buffer (const GstTagList *list
,const gchar *tag
,GstBuffer **value
); gboolean gst_tag_list_get_buffer_index (const GstTagList *list
,const gchar *tag
,guint index
,GstBuffer **value
);
List of tags and values used to describe media metadata.
Strings must be in ASCII or UTF-8 encoding. No other encodings are allowed.
Last reviewed on 2009-06-09 (0.10.23)
typedef enum { GST_TAG_MERGE_UNDEFINED, GST_TAG_MERGE_REPLACE_ALL, GST_TAG_MERGE_REPLACE, GST_TAG_MERGE_APPEND, GST_TAG_MERGE_PREPEND, GST_TAG_MERGE_KEEP, GST_TAG_MERGE_KEEP_ALL, /* add more */ GST_TAG_MERGE_COUNT } GstTagMergeMode;
The different tag merging modes are basically replace, overwrite and append,
but they can be seen from two directions. Given two taglists: (A) the tags
already in the element and (B) the ones that are supplied to the element (
e.g. via gst_tag_setter_merge_tags()
/ gst_tag_setter_add_tags()
or a
GST_EVENT_TAG
), how are these tags merged?
In the table below this is shown for the cases that a tag exists in the list
(A) or does not exists (!A) and combinations thereof.
Table 1. merge mode
merge mode | A + B | A + !B | !A + B | !A + !B |
---|---|---|---|---|
REPLACE_ALL | B | - | B | - |
REPLACE | B | A | B | - |
APPEND | A, B | A | B | - |
PREPEND | B, A | A | B | - |
KEEP | A | A | B | - |
KEEP_ALL | A | A | - | - |
undefined merge mode | |
replace all tags (clear list and append) | |
replace tags | |
append tags | |
prepend tags | |
keep existing tags | |
keep all existing tags | |
the number of merge modes |
typedef enum { GST_TAG_FLAG_UNDEFINED, GST_TAG_FLAG_META, GST_TAG_FLAG_ENCODED, GST_TAG_FLAG_DECODED, GST_TAG_FLAG_COUNT } GstTagFlag;
Extra tag flags used when registering tags.
void (*GstTagForeachFunc) (const GstTagList *list
,const gchar *tag
,gpointer user_data
);
A function that will be called in gst_tag_list_foreach()
. The function may
not modify the tag list.
|
the GstTagList |
|
a name of a tag in list
|
|
user data |
void (*GstTagMergeFunc) (GValue *dest
,const GValue *src
);
A function for merging multiple values of a tag used when registering tags.
#define GST_TAG_TITLE "title"
commonly used title (string)
The title as it should be displayed, e.g. 'The Doll House'
#define GST_TAG_TITLE_SORTNAME "title-sortname"
commonly used title, as used for sorting (string)
The title as it should be sorted, e.g. 'Doll House, The'
Since 0.10.15
#define GST_TAG_ARTIST "artist"
person(s) responsible for the recording (string)
The artist name as it should be displayed, e.g. 'Jimi Hendrix' or 'The Guitar Heroes'
#define GST_TAG_ARTIST_SORTNAME "musicbrainz-sortname"
person(s) responsible for the recording, as used for sorting (string)
The artist name as it should be sorted, e.g. 'Hendrix, Jimi' or 'Guitar Heroes, The'
Since 0.10.15
#define GST_TAG_ALBUM "album"
album containing this data (string)
The album name as it should be displayed, e.g. 'The Jazz Guitar'
#define GST_TAG_ALBUM_SORTNAME "album-sortname"
album containing this data, as used for sorting (string)
The album name as it should be sorted, e.g. 'Jazz Guitar, The'
Since 0.10.15
#define GST_TAG_ALBUM_ARTIST "album-artist"
The artist of the entire album, as it should be displayed.
Since 0.10.25
#define GST_TAG_ALBUM_ARTIST_SORTNAME "album-artist-sortname"
The artist of the entire album, as it should be sorted.
Since 0.10.25
#define GST_TAG_EXTENDED_COMMENT "extended-comment"
key/value text commenting the data (string)
Must be in the form of 'key=comment' or 'key[lc]=comment' where 'lc' is an ISO-639 language code.
This tag is used for unknown Vorbis comment tags, unknown APE tags and certain ID3v2 comment fields.
Since 0.10.10
#define GST_TAG_TRACK_NUMBER "track-number"
track number inside a collection (unsigned integer)
#define GST_TAG_TRACK_COUNT "track-count"
count of tracks inside collection this track belongs to (unsigned integer)
#define GST_TAG_ALBUM_VOLUME_NUMBER "album-disc-number"
disc number inside a collection (unsigned integer)
#define GST_TAG_ALBUM_VOLUME_COUNT "album-disc-count"
count of discs inside collection this disc belongs to (unsigned integer)
#define GST_TAG_LOCATION "location"
Origin of media as a URI (location, where the original of the file or stream is hosted) (string)
#define GST_TAG_HOMEPAGE "homepage"
Homepage for this media (i.e. artist or movie homepage) (string)
Since 0.10.23
#define GST_TAG_DESCRIPTION "description"
short text describing the content of the data (string)
#define GST_TAG_ISRC "isrc"
International Standard Recording Code - see http://www.ifpi.org/isrc/ (string)
#define GST_TAG_COPYRIGHT_URI "copyright-uri"
URI to location where copyright details can be found (string)
Since 0.10.14
#define GST_TAG_COMPOSER "composer"
person(s) who composed the recording (string)
Since 0.10.15
#define GST_TAG_LICENSE_URI "license-uri"
URI to location where license details can be found (string)
Since 0.10.14
#define GST_TAG_DURATION "duration"
length in GStreamer time units (nanoseconds) (unsigned 64-bit integer)
#define GST_TAG_VIDEO_CODEC "video-codec"
codec the video data is stored in (string)
#define GST_TAG_AUDIO_CODEC "audio-codec"
codec the audio data is stored in (string)
#define GST_TAG_SUBTITLE_CODEC "subtitle-codec"
codec/format the subtitle data is stored in (string)
Since 0.10.23
#define GST_TAG_CONTAINER_FORMAT "container-format"
container format the data is stored in (string)
Since 0.10.24
#define GST_TAG_BITRATE "bitrate"
exact or average bitrate in bits/s (unsigned integer)
#define GST_TAG_NOMINAL_BITRATE "nominal-bitrate"
nominal bitrate in bits/s (unsigned integer)
#define GST_TAG_MINIMUM_BITRATE "minimum-bitrate"
minimum bitrate in bits/s (unsigned integer)
#define GST_TAG_MAXIMUM_BITRATE "maximum-bitrate"
maximum bitrate in bits/s (unsigned integer)
#define GST_TAG_ENCODER_VERSION "encoder-version"
version of the encoder used to encode this stream (unsigned integer)
#define GST_TAG_REFERENCE_LEVEL "replaygain-reference-level"
reference level of track and album gain values (double)
Since 0.10.12
#define GST_TAG_LANGUAGE_CODE "language-code"
Language code (ISO-639-1) (string) of the content
#define GST_TAG_IMAGE "image"
image (buffer) (buffer caps should specify the content type and preferably also set "image-type" field as GstTagImageType)
Since 0.10.6
#define GST_TAG_PREVIEW_IMAGE "preview-image"
image that is meant for preview purposes, e.g. small icon-sized version (buffer) (buffer caps should specify the content type)
Since 0.10.7
#define GST_TAG_ATTACHMENT "attachment"
generic file attachment (buffer) (buffer caps should specify the content type and if possible set "filename" to the file name of the attachment)
Since 0.10.21
#define GST_TAG_BEATS_PER_MINUTE "beats-per-minute"
number of beats per minute in audio (double)
Since 0.10.12
#define GST_TAG_KEYWORDS "keywords"
comma separated keywords describing the content (string).
Since 0.10.21
#define GST_TAG_GEO_LOCATION_NAME "geo-location-name"
human readable descriptive location of where the media has been recorded or produced. (string).
Since 0.10.21
#define GST_TAG_GEO_LOCATION_LATITUDE "geo-location-latitude"
geo latitude location of where the media has been recorded or produced in degrees according to WGS84 (zero at the equator, negative values for southern latitudes) (double).
Since 0.10.21
#define GST_TAG_GEO_LOCATION_LONGITUDE "geo-location-longitude"
geo longitude location of where the media has been recorded or produced in degrees according to WGS84 (zero at the prime meridian in Greenwich/UK, negative values for western longitudes). (double).
Since 0.10.21
#define GST_TAG_GEO_LOCATION_ELEVATION "geo-location-elevation"
geo elevation of where the media has been recorded or produced in meters according to WGS84 (zero is average sea level) (double).
Since 0.10.21
#define GST_TAG_GEO_LOCATION_CITY "geo-location-city"
The city (english name) where the media has been produced (string).
Since 0.10.29
#define GST_TAG_GEO_LOCATION_COUNTRY "geo-location-country"
The country (english name) where the media has been produced (string).
Since 0.10.29
#define GST_TAG_GEO_LOCATION_SUBLOCATION "geo-location-sublocation"
A location 'smaller' than GST_TAG_GEO_LOCATION_CITY that specifies better where the media has been produced. (e.g. the neighborhood) (string).
This tag has been added as this is how it is handled/named in XMP's Iptc4xmpcore schema.
Since 0.10.29
#define GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION "geo-location-movement-direction"
Indicates the movement direction of the device performing the capture of a media. It is represented as degrees in floating point representation, 0 means the geographic north, and increases clockwise (double from 0 to 360)
See also GST_TAG_GEO_LOCATION_CAPTURE_DIRECTION
Since 0.10.30
#define GST_TAG_GEO_LOCATION_MOVEMENT_SPEED "geo-location-movement-speed"
Speed of the capturing device when performing the capture. Represented in m/s. (double)
See also GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION
Since 0.10.30
#define GST_TAG_GEO_LOCATION_CAPTURE_DIRECTION "geo-location-capture-direction"
Indicates the direction the device is pointing to when capturing a media. It is represented as degrees in floating point representation, 0 means the geographic north, and increases clockwise (double from 0 to 360)
See also GST_TAG_GEO_LOCATION_MOVEMENT_DIRECTION
Since 0.10.30
#define GST_TAG_SHOW_NAME "show-name"
Name of the show, used for displaying (string)
Since 0.10.26
#define GST_TAG_SHOW_SORTNAME "show-sortname"
Name of the show, used for sorting (string)
Since 0.10.26
#define GST_TAG_SHOW_EPISODE_NUMBER "show-episode-number"
Number of the episode within a season/show (unsigned integer)
Since 0.10.26
#define GST_TAG_SHOW_SEASON_NUMBER "show-season-number"
Number of the season of a show/series (unsigned integer)
Since 0.10.26
#define GST_TAG_COMPOSER_SORTNAME "composer-sortname"
The composer's name, used for sorting (string)
Since 0.10.26
#define GST_TAG_GROUPING "grouping"
Groups together media that are related and spans multiple tracks. An example are multiple pieces of a concerto. (string)
Since 0.10.26
#define GST_TAG_USER_RATING "user-rating"
Rating attributed by a person (likely the application user). The higher the value, the more the user likes this media (unsigned int from 0 to 100)
Since 0.10.29
#define GST_TAG_DEVICE_MANUFACTURER "device-manufacturer"
Manufacturer of the device used to create the media (string)
Since 0.10.30
#define GST_TAG_DEVICE_MODEL "device-model"
Model of the device used to create the media (string)
Since 0.10.30
#define GST_TAG_IMAGE_ORIENTATION "image-orientation"
Represents the 'Orientation' tag from EXIF. Defines how the image should be rotated and mirrored for display. (string)
This tag has a predefined set of allowed values: "rotate-0" "rotate-90" "rotate-180" "rotate-270" "flip-rotate-0" "flip-rotate-90" "flip-rotate-180" "flip-rotate-270"
The naming is adopted according to a possible transformation to perform on the image to fix its orientation, obviously equivalent operations will yield the same result.
Rotations indicated by the values are in clockwise direction and 'flip' means an horizontal mirroring.
Since 0.10.30
void gst_tag_register (const gchar *name
,GstTagFlag flag
,GType type
,const gchar *nick
,const gchar *blurb
,GstTagMergeFunc func
);
Registers a new tag type for the use with GStreamer's type system. If a type with that name is already registered, that one is used. The old registration may have used a different type however. So don't rely on your supplied values.
Important: if you do not supply a merge function the implication will be that there can only be one single value for this tag in a tag list and any additional values will silenty be discarded when being added (unless GST_TAG_MERGE_REPLACE, GST_TAG_MERGE_REPLACE_ALL, or GST_TAG_MERGE_PREPEND is used as merge mode, in which case the new value will replace the old one in the list).
The merge function will be called from gst_tag_list_copy_value()
when
it is required that one or more values for a tag be condensed into
one single value. This may happen from gst_tag_list_get_string()
,
gst_tag_list_get_int()
, gst_tag_list_get_double()
etc. What will happen
exactly in that case depends on how the tag was registered and if a
merge function was supplied and if so which one.
Two default merge functions are provided: gst_tag_merge_use_first()
and
gst_tag_merge_strings_with_comma()
.
|
the name or identifier string |
|
a flag describing the type of tag info |
|
the type this data is in |
|
human-readable name |
|
a human-readable description about this tag |
|
function for merging multiple values of this tag, or NULL |
void gst_tag_merge_use_first (GValue *dest
,const GValue *src
);
This is a convenience function for the func argument of gst_tag_register()
.
It creates a copy of the first value from the list.
|
uninitialized GValue to store result in |
|
GValue to copy from |
void gst_tag_merge_strings_with_comma (GValue *dest
,const GValue *src
);
This is a convenience function for the func argument of gst_tag_register()
.
It concatenates all given strings using a comma. The tag must be registered
as a G_TYPE_STRING or this function will fail.
|
uninitialized GValue to store result in |
|
GValue to copy from |
gboolean gst_tag_exists (const gchar *tag
);
Checks if the given type is already registered.
|
name of the tag |
Returns : |
TRUE if the type is already registered |
GType gst_tag_get_type (const gchar *tag
);
Gets the GType used for this tag.
|
the tag |
Returns : |
the GType of this tag |
const gchar * gst_tag_get_nick (const gchar *tag
);
Returns the human-readable name of this tag, You must not change or free this string.
|
the tag |
Returns : |
the human-readable name of this tag |
const gchar * gst_tag_get_description (const gchar *tag
);
Returns the human-readable description of this tag, You must not change or free this string.
|
the tag |
Returns : |
the human-readable description of this tag |
GstTagFlag gst_tag_get_flag (const gchar *tag
);
Gets the flag of tag
.
|
the tag |
Returns : |
the flag of this tag. |
gboolean gst_tag_is_fixed (const gchar *tag
);
Checks if the given tag is fixed. A fixed tag can only contain one value. Unfixed tags can contain lists of values.
|
tag to check |
Returns : |
TRUE, if the given tag is fixed. |
GstTagList * gst_tag_list_new (void
);
Creates a new empty GstTagList.
Returns : |
An empty tag list |
GstTagList * gst_tag_list_new_full (const gchar *tag
,...
);
Creates a new taglist and appends the values for the given tags. It expects
tag-value pairs like gst_tag_list_add()
, and a NULL terminator after the
last pair. The type of the values is implicit and is documented in the API
reference, but can also be queried at runtime with gst_tag_get_type()
. It
is an error to pass a value of a type not matching the tag type into this
function. The tag list will make copies of any arguments passed
(e.g. strings, buffers).
|
tag |
|
NULL-terminated list of values to set |
Returns : |
a new GstTagList. Free with gst_tag_list_free() when no longer
needed.
|
Since 0.10.24
GstTagList * gst_tag_list_new_full_valist (va_list var_args
);
Just like gst_tag_list_new_full()
, only that it takes a va_list argument.
Useful mostly for language bindings.
|
tag / value pairs to set |
Returns : |
a new GstTagList. Free with gst_tag_list_free() when no longer
needed.
|
Since 0.10.24
gboolean gst_is_tag_list (gconstpointer p
);
Checks if the given pointer is a taglist.
|
Object that might be a taglist |
Returns : |
TRUE, if the given pointer is a taglist |
gboolean gst_tag_list_is_empty (const GstTagList *list
);
Checks if the given taglist is empty.
|
A GstTagList. |
Returns : |
TRUE if the taglist is empty, otherwise FALSE. |
Since 0.10.11
GstTagList * gst_tag_list_copy (const GstTagList *list
);
Copies a given GstTagList.
|
list to copy |
Returns : |
copy of the given list |
void gst_tag_list_insert (GstTagList *into
,const GstTagList *from
,GstTagMergeMode mode
);
Inserts the tags of the from
list into the first list using the given mode.
|
list to merge into |
|
list to merge from |
|
the mode to use |
GstTagList * gst_tag_list_merge (const GstTagList *list1
,const GstTagList *list2
,GstTagMergeMode mode
);
Merges the two given lists into a new list. If one of the lists is NULL, a copy of the other is returned. If both lists are NULL, NULL is returned.
|
first list to merge |
|
second list to merge |
|
the mode to use |
Returns : |
the new list |
void gst_tag_list_free (GstTagList *list
);
Frees the given list and all associated values.
|
the list to free |
guint gst_tag_list_get_tag_size (const GstTagList *list
,const gchar *tag
);
Checks how many value are stored in this tag list for the given tag.
|
a taglist |
|
the tag to query |
Returns : |
The number of tags stored |
void gst_tag_list_add (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,...
);
Sets the values for the given tags using the specified mode.
|
list to set tags in |
|
the mode to use |
|
tag |
|
NULL-terminated list of values to set |
void gst_tag_list_add_value (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,const GValue *value
);
Sets the GValue for a given tag using the specified mode.
|
list to set tags in |
|
the mode to use |
|
tag |
|
GValue for this tag |
Since 0.10.24
void gst_tag_list_add_values (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,...
);
Sets the GValues for the given tags using the specified mode.
|
list to set tags in |
|
the mode to use |
|
tag |
|
GValues to set |
void gst_tag_list_add_valist (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,va_list var_args
);
Sets the values for the given tags using the specified mode.
|
list to set tags in |
|
the mode to use |
|
tag |
|
tag / value pairs to set |
void gst_tag_list_add_valist_values (GstTagList *list
,GstTagMergeMode mode
,const gchar *tag
,va_list var_args
);
Sets the GValues for the given tags using the specified mode.
|
list to set tags in |
|
the mode to use |
|
tag |
|
tag / GValue pairs to set |
void gst_tag_list_remove_tag (GstTagList *list
,const gchar *tag
);
Removes the given tag from the taglist.
|
list to remove tag from |
|
tag to remove |
void gst_tag_list_foreach (const GstTagList *list
,GstTagForeachFunc func
,gpointer user_data
);
Calls the given function for each tag inside the tag list. Note that if there is no tag, the function won't be called at all.
|
list to iterate over |
|
function to be called for each tag |
|
user specified data |
const GValue * gst_tag_list_get_value_index (const GstTagList *list
,const gchar *tag
,guint index
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList |
|
tag to read out |
|
number of entry to read out |
Returns : |
The GValue for the specified entry or NULL if the tag wasn't available or the tag doesn't have as many entries |
gboolean gst_tag_list_copy_value (GValue *dest
,const GstTagList *list
,const gchar *tag
);
Copies the contents for the given tag into the value,
merging multiple values into one if multiple values are associated
with the tag.
You must g_value_unset()
the value after use.
|
uninitialized GValue to copy into |
|
list to get the tag from |
|
tag to read out |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_char (const GstTagList *list
,const gchar *tag
,gchar *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_char_index (const GstTagList *list
,const gchar *tag
,guint index
,gchar *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uchar (const GstTagList *list
,const gchar *tag
,guchar *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uchar_index (const GstTagList *list
,const gchar *tag
,guint index
,guchar *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_boolean (const GstTagList *list
,const gchar *tag
,gboolean *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_boolean_index (const GstTagList *list
,const gchar *tag
,guint index
,gboolean *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_int (const GstTagList *list
,const gchar *tag
,gint *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_int_index (const GstTagList *list
,const gchar *tag
,guint index
,gint *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uint (const GstTagList *list
,const gchar *tag
,guint *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uint_index (const GstTagList *list
,const gchar *tag
,guint index
,guint *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_long (const GstTagList *list
,const gchar *tag
,glong *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_long_index (const GstTagList *list
,const gchar *tag
,guint index
,glong *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_ulong (const GstTagList *list
,const gchar *tag
,gulong *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_ulong_index (const GstTagList *list
,const gchar *tag
,guint index
,gulong *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_int64 (const GstTagList *list
,const gchar *tag
,gint64 *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_int64_index (const GstTagList *list
,const gchar *tag
,guint index
,gint64 *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uint64 (const GstTagList *list
,const gchar *tag
,guint64 *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_uint64_index (const GstTagList *list
,const gchar *tag
,guint index
,guint64 *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_float (const GstTagList *list
,const gchar *tag
,gfloat *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_float_index (const GstTagList *list
,const gchar *tag
,guint index
,gfloat *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_double (const GstTagList *list
,const gchar *tag
,gdouble *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_double_index (const GstTagList *list
,const gchar *tag
,guint index
,gdouble *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_string (const GstTagList *list
,const gchar *tag
,gchar **value
);
Copies the contents for the given tag into the value, possibly merging multiple values into one if multiple values are associated with the tag.
Use gst_tag_list_get_string_index (list, tag, 0, value) if you want to retrieve the first string associated with this tag unmodified.
The resulting string in value
will be in UTF-8 encoding and should be
freed by the caller using g_free when no longer needed. Since 0.10.24 the
returned string is also guaranteed to be non-NULL and non-empty.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_string_index (const GstTagList *list
,const gchar *tag
,guint index
,gchar **value
);
Gets the value that is at the given index for the given tag in the given list.
The resulting string in value
will be in UTF-8 encoding and should be
freed by the caller using g_free when no longer needed. Since 0.10.24 the
returned string is also guaranteed to be non-NULL and non-empty.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_peek_string_index (const GstTagList *list
,const gchar *tag
,guint index
,const gchar **value
);
Peeks at the value that is at the given index for the given tag in the given list.
The resulting string in value
will be in UTF-8 encoding and doesn't need
to be freed by the caller. The returned string is also guaranteed to
be non-NULL and non-empty.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was set, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_pointer (const GstTagList *list
,const gchar *tag
,gpointer *value
);
Copies the contents for the given tag into the value, merging multiple values into one if multiple values are associated with the tag.
|
a GstTagList to get the tag from |
|
tag to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_pointer_index (const GstTagList *list
,const gchar *tag
,guint index
,gpointer *value
);
Gets the value that is at the given index for the given tag in the given list.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list. |
gboolean gst_tag_list_get_date (const GstTagList *list
,const gchar *tag
,GDate **value
);
Copies the first date for the given tag in the taglist into the variable
pointed to by value
. Free the date with g_date_free()
when it is no longer
needed.
|
a GstTagList to get the tag from |
|
tag to read out |
|
address of a GDate pointer variable to store the result into |
Returns : |
TRUE, if a date was copied, FALSE if the tag didn't exist in the given list or if it was NULL. |
gboolean gst_tag_list_get_date_index (const GstTagList *list
,const gchar *tag
,guint index
,GDate **value
);
Gets the date that is at the given index for the given tag in the given
list and copies it into the variable pointed to by value
. Free the date
with g_date_free()
when it is no longer needed.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
location for the result |
Returns : |
TRUE, if a value was copied, FALSE if the tag didn't exist in the given list or if it was NULL. |
gboolean gst_tag_list_get_buffer (const GstTagList *list
,const gchar *tag
,GstBuffer **value
);
Copies the first buffer for the given tag in the taglist into the variable
pointed to by value
. Free the buffer with gst_buffer_unref()
when it is
no longer needed.
|
a GstTagList to get the tag from |
|
tag to read out |
|
address of a GstBuffer pointer variable to store the result into |
Returns : |
TRUE, if a buffer was copied, FALSE if the tag didn't exist in the given list or if it was NULL. |
Since 0.10.23
gboolean gst_tag_list_get_buffer_index (const GstTagList *list
,const gchar *tag
,guint index
,GstBuffer **value
);
Gets the buffer that is at the given index for the given tag in the given
list and copies it into the variable pointed to by value
. Free the buffer
with gst_buffer_unref()
when it is no longer needed.
|
a GstTagList to get the tag from |
|
tag to read out |
|
number of entry to read out |
|
address of a GstBuffer pointer variable to store the result into |
Returns : |
TRUE, if a buffer was copied, FALSE if the tag didn't exist in the given list or if it was NULL. |
Since 0.10.23