gst_tag_register_musicbrainz_tags ()

void
gst_tag_register_musicbrainz_tags (void);

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.

gst_tag_freeform_string_to_utf8 ()

gchar *
gst_tag_freeform_string_to_utf8 (const gchar *data,
                                 gint size,
                                 const gchar **env_vars);

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).

gst_tag_parse_extended_comment ()

gboolean
gst_tag_parse_extended_comment (const gchar *ext_comment,
                                gchar **key,
                                gchar **lang,
                                gchar **value,
                                gboolean fail_if_no_key);

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.

gst_tag_image_data_to_image_sample ()

GstSample *
gst_tag_image_data_to_image_sample (const guint8 *image_data,
                                    guint image_data_len,
                                    GstTagImageType image_type);

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 GstSamples 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).

GST_TAG_MUSICBRAINZ_TRACKID

#define GST_TAG_MUSICBRAINZ_TRACKID "musicbrainz-trackid"

MusicBrainz track ID

GST_TAG_MUSICBRAINZ_ARTISTID

#define GST_TAG_MUSICBRAINZ_ARTISTID "musicbrainz-artistid"

MusicBrainz artist ID

GST_TAG_MUSICBRAINZ_ALBUMID

#define GST_TAG_MUSICBRAINZ_ALBUMID "musicbrainz-albumid"

MusicBrainz album ID

GST_TAG_MUSICBRAINZ_ALBUMARTISTID

#define GST_TAG_MUSICBRAINZ_ALBUMARTISTID "musicbrainz-albumartistid"

MusicBrainz album artist ID

GST_TAG_MUSICBRAINZ_TRMID

#define GST_TAG_MUSICBRAINZ_TRMID "musicbrainz-trmid"

MusicBrainz track TRM ID

GST_TAG_CDDA_CDDB_DISCID

#define GST_TAG_CDDA_CDDB_DISCID              "discid"

CDDB disc id in its short form (e.g. 'aa063d0f')

GST_TAG_CDDA_CDDB_DISCID_FULL

#define GST_TAG_CDDA_CDDB_DISCID_FULL         "discid-full"

CDDB disc id including all details

GST_TAG_CDDA_MUSICBRAINZ_DISCID

#define GST_TAG_CDDA_MUSICBRAINZ_DISCID       "musicbrainz-discid"

Musicbrainz disc id (e.g. 'ahg7JUcfR3vCYBphSDIogOOWrr0-')

GST_TAG_CDDA_MUSICBRAINZ_DISCID_FULL

#define GST_TAG_CDDA_MUSICBRAINZ_DISCID_FULL  "musicbrainz-discid-full"

Musicbrainz disc id details

GST_TAG_CMML_CLIP

#define GST_TAG_CMML_CLIP "cmml-clip"

Annodex CMML clip element tag

GST_TAG_CMML_HEAD

#define GST_TAG_CMML_HEAD "cmml-head"

Annodex CMML head element tag

GST_TAG_CMML_STREAM

#define GST_TAG_CMML_STREAM "cmml-stream"

Annodex CMML stream element tag

GST_TAG_CAPTURING_SHUTTER_SPEED

#define GST_TAG_CAPTURING_SHUTTER_SPEED        "capturing-shutter-speed"

Shutter speed used when capturing an image, in seconds. (fraction)

GST_TAG_CAPTURING_FOCAL_RATIO

#define GST_TAG_CAPTURING_FOCAL_RATIO          "capturing-focal-ratio"

Focal ratio (f-number) used when capturing an image. (double)

The value stored is the denominator of the focal ratio (f-number). For example, if this tag value is 2, the focal ratio is f/2.

GST_TAG_CAPTURING_FOCAL_LENGTH

#define GST_TAG_CAPTURING_FOCAL_LENGTH         "capturing-focal-length"

Focal length used when capturing an image, in mm. (double)

GST_TAG_CAPTURING_DIGITAL_ZOOM_RATIO

#define GST_TAG_CAPTURING_DIGITAL_ZOOM_RATIO   "capturing-digital-zoom-ratio"

Digital zoom ratio used when capturing an image. (double)

GST_TAG_CAPTURING_ISO_SPEED

#define GST_TAG_CAPTURING_ISO_SPEED           "capturing-iso-speed"

ISO speed used when capturing an image. (integer)

GST_TAG_CAPTURING_EXPOSURE_PROGRAM

#define GST_TAG_CAPTURING_EXPOSURE_PROGRAM     "capturing-exposure-program"

Type of exposure control used when capturing an image. (string)

The allowed values are: "undefined" "manual" "normal" - automatically controlled "aperture-priority" - user selects aperture value "shutter-priority" - user selects shutter speed "creative" - biased towards depth of field "action" - biased towards fast shutter speed "portrait" - closeup, leaving background out of focus "landscape" - landscape photos, background in focus

GST_TAG_CAPTURING_EXPOSURE_MODE

#define GST_TAG_CAPTURING_EXPOSURE_MODE       "capturing-exposure-mode"

Exposure mode used when capturing an image. (string)

The allowed values are: "auto-exposure" "manual-exposure" "auto-bracket"

GST_TAG_CAPTURING_SCENE_CAPTURE_TYPE

#define GST_TAG_CAPTURING_SCENE_CAPTURE_TYPE  "capturing-scene-capture-type"

Scene mode used when capturing an image. (string)

The allowed values are: "standard" "landscape" "portrait" "night-scene"

GST_TAG_CAPTURING_GAIN_ADJUSTMENT

#define GST_TAG_CAPTURING_GAIN_ADJUSTMENT     "capturing-gain-adjustment"

Gain adjustment applied to an image. (string)

The allowed values are: "none" "low-gain-up" "high-gain-up" "low-gain-down" "high-gain-down"

GST_TAG_CAPTURING_WHITE_BALANCE

#define GST_TAG_CAPTURING_WHITE_BALANCE       "capturing-white-balance"

White balance mode used when capturing an image. (string)

The allowed values are: "auto" "manual" "daylight" "cloudy" "tungsten" "fluorescent" "fluorescent h" (newer daylight-calibrated fluorescents) "flash"

GST_TAG_CAPTURING_CONTRAST

#define GST_TAG_CAPTURING_CONTRAST            "capturing-contrast"

Direction of contrast processing applied when capturing an image. (string)

The allowed values are: "normal" "soft" "hard"

GST_TAG_CAPTURING_SATURATION

#define GST_TAG_CAPTURING_SATURATION          "capturing-saturation"

Direction of saturation processing applied when capturing an image. (string)

The allowed values are: "normal" "low-saturation" "high-saturation"

GST_TAG_CAPTURING_SHARPNESS

#define GST_TAG_CAPTURING_SHARPNESS          "capturing-sharpness"

Direction of sharpness processing applied when capturing an image. (string)

The allowed values are: "normal" "soft" "hard"

GST_TAG_CAPTURING_FLASH_FIRED

#define GST_TAG_CAPTURING_FLASH_FIRED         "capturing-flash-fired"

If flash was fired during the capture of an image. (boolean)

Note that if this tag isn't present, it should not be assumed that the flash did not fire. It should be treated as unknown.

GST_TAG_CAPTURING_FLASH_MODE

#define GST_TAG_CAPTURING_FLASH_MODE         "capturing-flash-mode"

The flash mode selected during the capture of an image. (string)

The allowed values are: "auto" "always" "never"

GST_TAG_CAPTURING_METERING_MODE

#define GST_TAG_CAPTURING_METERING_MODE      "capturing-metering-mode"

Defines the way a camera determines the exposure. (string)

The allowed values are: "unknown" "average" "center-weighted-average" "spot" "multi-spot" "pattern" "partial" "other"

GST_TAG_CAPTURING_SOURCE

#define GST_TAG_CAPTURING_SOURCE             "capturing-source"

Indicates the source of capture. The device/medium used to do the capture. (string)

Allowed values are: "dsc" (= digital still camera) "transparent-scanner" "reflex-scanner" "other"

GST_TAG_CAPTURING_EXPOSURE_COMPENSATION

#define GST_TAG_CAPTURING_EXPOSURE_COMPENSATION "capturing-exposure-compensation"

Exposure compensation using when capturing an image in EV. (double)

GST_TAG_IMAGE_HORIZONTAL_PPI

#define GST_TAG_IMAGE_HORIZONTAL_PPI         "image-horizontal-ppi"

Media (image/video) intended horizontal pixel density in ppi. (double)

GST_TAG_IMAGE_VERTICAL_PPI

#define GST_TAG_IMAGE_VERTICAL_PPI           "image-vertical-ppi"

Media (image/video) intended vertical pixel density in ppi. (double)

GST_TAG_ID3V2_HEADER_SIZE

#define GST_TAG_ID3V2_HEADER_SIZE            10

ID3V2 header size considered minimum input for some functions such as gst_tag_list_from_id3v2_tag() and gst_tag_get_id3v2_tag_size() for example.

GST_TAG_MUSICAL_KEY

#define GST_TAG_MUSICAL_KEY                   "musical-key"

Musical key in which the sound starts. It is represented as a string with a maximum length of three characters. The ground keys are represented with "A","B","C","D","E", "F" and "G" and halfkeys represented with "b" and "#". Minor is represented as "m" (e.g. "Dbm"). Off key is represented with an "o" only. This notation might be extended in the future to support non-minor/major keys.

Since: 1.2

enum GstTagImageType

Type of image contained in an image tag (specified as "image-type" field in the info structure in the image's GstSample)