gstreamer-tag-1.0

---

Description:

GStreamer Tag Support Library

• Home: https://gstreamer.freedesktop.org/
• C-Documentation: https://gstreamer.freedesktop.org/documentation/tag/index.html
• Devhelp-Package download

Content:

Namespaces:

• Gst
• Tag

Interfaces:

• XmpWriter - This interface is implemented by elements that are able to do XMP serialization.

Classes:

• Demux - Provides a base class for demuxing tags at the beginning or end of a stream and handles things like typefinding, querying, seeking, and different modes of operation (chain-based, pull_range-based, and providing downstream elements with random access if upstream supports that).
• Mux - Provides a base class for adding tags at the beginning or end of a stream.

Enums:

• DemuxResult - Result values from the parse_tag virtual function.
• ImageType - Type of image contained in an image tag (specified as "image-type" field in the info structure in the image's Sample)
• LicenseFlags - See http://creativecommons.

Constants:

• public const string ACOUSTID_FINGERPRINT
  AcoustID Fingerprint (Chromaprint)
• public const string ACOUSTID_ID
  AcoustID Identifier
• public const int ID3V2_HEADER_SIZE
  ID3V2 header size considered minimum input for some functions such as from_id3v2_tag and get_id3v2_tag_size for example.
• public const string MUSICAL_KEY
  Musical key in which the sound starts.

Methods:

• public bool check_language_code (string lang_code)
  Check if a given string contains a known ISO 639 language code.
• public string? freeform_string_to_utf8 (char[] data, string[] env_vars)
  Convenience function to read a string with unknown character encoding.
• public unowned string? from_id3_tag (string id3_tag)
  Looks up the GStreamer tag for a ID3v2 tag.
• public unowned string? from_id3_user_tag (string type, string id3_user_tag)
  Looks up the GStreamer tag for an ID3v2 user tag (e.g. description in TXXX frame or owner in UFID frame).
• public unowned string? from_vorbis_tag (string vorbis_tag)
  Looks up the GStreamer tag for a vorbiscomment tag.
• public uint get_id3v2_tag_size (Buffer buffer)
  Determines size of an ID3v2 tag on buffer containing at least ID3v2 header, i.e. at least ID3V2_HEADER_SIZE (10) bytes;
• public unowned string? get_language_code_iso_639_1 (string lang_code)
  Returns two-letter ISO-639-1 language code given a three-letter ISO-639-2 language code or two-letter ISO-639-1 language code (both are accepted for convenience).
• public unowned string? get_language_code_iso_639_2B (string lang_code)
  Returns three-letter ISO-639-2 "bibliographic" language code given a two-letter ISO-639-1 language code or a three-letter ISO-639-2 language code (both are accepted for convenience).
• public unowned string? get_language_code_iso_639_2T (string lang_code)
  Returns three-letter ISO-639-2 "terminological" language code given a two-letter ISO-639-1 language code or a three-letter ISO-639-2 language code (both are accepted for convenience).
• public string[] get_language_codes ()
  Returns a list of known language codes (in form of two-letter ISO-639-1 codes).
• public unowned string? get_language_name (string language_code)
  Returns the name of the language given an ISO-639 language code as found in a GST_TAG_LANGUAGE_CODE tag.
• public unowned string? get_license_description (string license_ref)
  Get the description of a license, which is a translated description of the license's main features.
• public LicenseFlags get_license_flags (string license_ref)
  Get the flags of a license, which describe most of the features of a license in their most general form.
• public unowned string? get_license_jurisdiction (string license_ref)
  Get the jurisdiction code of a license.
• public unowned string? get_license_nick (string license_ref)
  Get the nick name of a license, which is a short (untranslated) string such as e.g. "CC BY-NC-ND 2.0 UK".
• public unowned string? get_license_title (string license_ref)
  Get the title of a license, which is a short translated description of the license's features (generally not very pretty though).
• public unowned string? get_license_version (string license_ref)
  Get the version of a license.
• public string[] get_licenses ()
  Returns a list of known license references (in form of URIs).
• public uint id3_genre_count ()
  Gets the number of ID3v1 genres that can be identified.
• public unowned string? id3_genre_get (uint id)
  Gets the ID3v1 genre name for a given ID.
• public Sample? image_data_to_image_sample (uint8[] image_data, ImageType image_type)
  Helper function for tag-reading plugins to create a Sample suitable to add to a TagList as an image tag (such as IMAGE or PREVIEW_IMAGE) from the encoded image data and an (optional) image type.
• public bool parse_extended_comment (string ext_comment, out string? key, out string? lang, out string value, bool fail_if_no_key)
  Convenience function to parse a GST_TAG_EXTENDED_COMMENT string and separate it into its components.
• public void register_musicbrainz_tags ()
  Registers additional musicbrainz-specific tags with the GStreamer tag system.
• public unowned string? to_id3_tag (string gst_tag)
  Looks up the ID3v2 tag for a GStreamer tag.
• public List<string> to_vorbis_comments (TagList list, string tag)
  Creates a new tag list that contains the information parsed out of a vorbiscomment packet.
• public unowned string? to_vorbis_tag (string gst_tag)
  Looks up the vorbiscomment tag for a GStreamer tag.
• public void vorbis_tag_add (TagList list, string tag, string value)
  Convenience function using from_vorbis_tag, parsing a vorbis comment string into the right type and adding it to the given taglist list.
• public unowned string[] xmp_list_schemas ()
  Gets the list of supported schemas in the xmp lib
• CDDA

Constants:

• public const string CDDB_DISCID
  CDDB disc id in its short form (e.g. 'aa063d0f')
• public const string CDDB_DISCID_FULL
  CDDB disc id including all details
• public const string MUSICBRAINZ_DISCID
  Musicbrainz disc id (e.g. 'ahg7JUcfR3vCYBphSDIogOOWrr0-')
• public const string MUSICBRAINZ_DISCID_FULL
  Musicbrainz disc id details
• CMML

Constants:

• public const string CLIP
  Annodex CMML clip element tag
• public const string HEAD
  Annodex CMML head element tag
• public const string STREAM
  Annodex CMML stream element tag
• Capturing

Constants:

• public const string CONTRAST
  Direction of contrast processing applied when capturing an image.
• public const string DIGITAL_ZOOM_RATIO
  Digital zoom ratio used when capturing an image.
• public const string EXPOSURE_COMPENSATION
  Exposure compensation using when capturing an image in EV.
• public const string EXPOSURE_MODE
  Exposure mode used when capturing an image.
• public const string EXPOSURE_PROGRAM
  Type of exposure control used when capturing an image.
• public const string FLASH_FIRED
  If flash was fired during the capture of an image.
• public const string FLASH_MODE
  The flash mode selected during the capture of an image.
• public const string FOCAL_LENGTH
  Focal length used when capturing an image, in mm.
• public const string FOCAL_LENGTH_35_MM
  35 mm equivalent focal length used when capturing an image, in mm.
• public const string FOCAL_RATIO
  Focal ratio (f-number) used when capturing an image.
• public const string GAIN_ADJUSTMENT
  Gain adjustment applied to an image.
• public const string ISO_SPEED
  ISO speed used when capturing an image.
• public const string METERING_MODE
  Defines the way a camera determines the exposure.
• public const string SATURATION
  Direction of saturation processing applied when capturing an image.
• public const string SCENE_CAPTURE_TYPE
  Scene mode used when capturing an image.
• public const string SHARPNESS
  Direction of sharpness processing applied when capturing an image.
• public const string SHUTTER_SPEED
  Shutter speed used when capturing an image, in seconds.
• public const string SOURCE
  Indicates the source of capture.
• public const string WHITE_BALANCE
  White balance mode used when capturing an image.
• Image

Constants:

• public const string HORIZONTAL_PPI
  Media (image/video) intended horizontal pixel density in ppi.
• public const string VERTICAL_PPI
  Media (image/video) intended vertical pixel density in ppi.
• List

Methods:

• public bool add_id3_image (TagList tag_list, uint8[] image_data, uint id3_picture_type)
  Adds an image from an ID3 APIC frame (or similar, such as used in FLAC) to the given tag list.
• public TagList from_exif_buffer (Buffer buffer, int byte_order, uint32 base_offset)
  Parses the IFD and IFD tags data contained in the buffer and puts it on a taglist.
• public TagList from_exif_buffer_with_tiff_header (Buffer buffer)
  Parses the exif tags starting with a tiff header structure.
• public TagList? from_id3v2_tag (Buffer buffer)
  Creates a new tag list that contains the information parsed out of a ID3 tag.
• public TagList? from_vorbiscomment (uint8[] data, uint8[] id_data, out string vendor_string)
  Creates a new tag list that contains the information parsed out of a vorbiscomment packet.
• public TagList? from_vorbiscomment_buffer (Buffer buffer, uint8[] id_data, out string vendor_string)
  Creates a new tag list that contains the information parsed out of a vorbiscomment packet.
• public TagList? from_xmp_buffer (Buffer buffer)
  Parse a xmp packet into a taglist.
• public TagList? new_from_id3v1 (uint8[] data)
  Parses the data containing an ID3v1 tag and returns a TagList from the parsed data.
• public Buffer to_exif_buffer (TagList taglist, int byte_order, uint32 base_offset)
  Formats the tags in taglist on exif format.
• public Buffer to_exif_buffer_with_tiff_header (TagList taglist)
  Formats the tags in taglist into exif structure, a tiff header is put in the beginning of the buffer.
• public Buffer to_vorbiscomment_buffer (TagList list, uint8[] id_data, string? vendor_string)
  Creates a new vorbiscomment buffer from a tag list.
• public Buffer? to_xmp_buffer (TagList list, bool read_only, string[] schemas)
  Formats a taglist as a xmp packet using only the selected schemas.
• MusicBrainz

Constants:

• public const string ALBUMARTISTID
  MusicBrainz album artist ID
• public const string ALBUMID
  MusicBrainz album ID
• public const string ARTISTID
  MusicBrainz artist ID
• public const string RELEASEGROUPID
  MusicBrainz Release Group ID
• public const string RELEASETRACKID
  MusicBrainz Release Track ID
• public const string TRACKID
  MusicBrainz track ID
• public const string TRMID
  MusicBrainz track TRM ID