Class
GExiv2Metadata
Description [src]
class GExiv2.Metadata : GObject.Object
{
/* No available fields */
}
An object holding all the Exiv2 metadata. Previews, if present, are also available.
It is a generic object that provides everything from simple aggregated accessors to common data such as image comments up to fine-grained access to specific tags of a specfic format, be it EXIF, IPTC or XMP.
As gexiv2 is only a wrapper around Exiv2, it’s better to read its documentation to understand the full scope of what it offers: http://www.exiv2.org/
In particular, rather than providing a getter/setter method pair for every metadata value available for images (of which there are thousands), Exiv2 uses a dotted addressing scheme. For example, to access a photo’s EXIF Orientation field, the caller passes to Exiv2 “Exif.Photo.Orientation”. These tags (in Exiv2 parlance) are key to using Exiv2 (and therefore gexiv2) to its fullest.
A full reference for all supported Exiv2 tags can be found at http://www.exiv2.org/metadata.html.
Functions
gexiv2_metadata_get_xmp_namespace_for_tag
Look up the URI for the namespace for tag.
unstable since: 0.16.0
gexiv2_metadata_try_get_tag_description
Get Exiv2’s description for a tag.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_xmp_namespace_for_tag
Look up the URI for the namespace for tag.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_register_xmp_namespace
Register an additional XMP namespace.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_unregister_all_xmp_namespaces
Unregister all XMP namespaces that have been previously registered with
gexiv2_metadata_try_register_xmp_namespace().
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_unregister_xmp_namespace
Unregister a namespace previously registered with
gexiv2_metadata_try_register_xmp_namespace().
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_unregister_all_xmp_namespaces
Unregister all XMP namespaces that have been previously registered with
gexiv2_metadata_try_register_xmp_namespace().
unstable since: 0.16.0
gexiv2_metadata_unregister_xmp_namespace
Unregister a namespace previously registered with
gexiv2_metadata_try_register_xmp_namespace().
unstable since: 0.16.0
Instance methods
gexiv2_metadata_as_bytes
Saves the metadata to the stream by reading the stream into memory, copying this object’s metadata into the image, then writing the image as a stream back out.
unstable since: 0.16.0
gexiv2_metadata_clear_comment
This is a composite clear method that will clear a number of fields. See
gexiv2_metadata_get_comment() for more information.
gexiv2_metadata_delete_gps_info
Removes all GPS metadata from the loaded image.
unstable since: 0.16.0
gexiv2_metadata_from_app1_segment
Load only an EXIF buffer, typically stored in a JPEG’s APP1 segment.
gexiv2_metadata_from_stream
Read metadata from a GInputStream. This function is not very
efficient in places since it needs to copy memory to fullfil underlying
requirements by exiv2, which expects everything to be memory-mappable.
gexiv2_metadata_generate_xmp_packet
Encode the XMP packet as a NULL-terminated string.
unstable since: 0.16.0
gexiv2_metadata_get_comment
A composite accessor that uses the first available metadata field from a list of well-known locations to find the photo’s comment (or description).
unstable since: 0.16.0
gexiv2_metadata_get_exif_data
Returns a binary blob of the contained EXIF data, if the image contains any.
since: 0.12.2
gexiv2_metadata_get_exif_tag_rational
Fetch EXIF tag represented by a fraction. nom will contain the numerator,
den the denominator of the fraction on successful return.
unstable since: 0.16.0
gexiv2_metadata_get_exposure_time
Returns the exposure time in seconds (shutter speed, not date-time of exposure) as a rational. See https://en.wikipedia.org/wiki/Shutter_speed for more information.
unstable since: 0.16.0
gexiv2_metadata_get_fnumber
See https://en.wikipedia.org/wiki/F-number for more information. If Exif.Photo.FNumber does not exist, it will fall back to calculating the FNumber from Exif.Photo.ApertureValue (if available).
unstable since: 0.16.0
gexiv2_metadata_get_focal_length
See https://en.wikipedia.org/wiki/Flange_focal_distance for more information.
unstable since: 0.16.0
gexiv2_metadata_get_gps_altitude
Convenience function to query the altitude stored in the GPS tags of the image.
unstable since: 0.16.0
gexiv2_metadata_get_gps_info
Convenience function to query all available GPS information at once. See the
gexiv2_metadata_get_gps_longitude(), gexiv2_metadata_get_gps_latitude()
and gexiv2_metadata_get_gps_altitude() for possible values of the out parameters.
unstable since: 0.16.0
gexiv2_metadata_get_gps_latitude
Query the latitude stored in the GPS tags of self.
unstable since: 0.16.0
gexiv2_metadata_get_gps_longitude
Query the longitude stored in the GPS tags of self.
unstable since: 0.16.0
gexiv2_metadata_get_iso_speed
See https://en.wikipedia.org/wiki/Iso_speed for more information.
unstable since: 0.16.0
gexiv2_metadata_get_metadata_pixel_height
Composite accessor to query the pixel with stored in the metadata. This
might differ from the height of image that is available through
gexiv2_metadata_get_pixel_height().
unstable since: 0.16.0
gexiv2_metadata_get_metadata_pixel_width
Composite accessor to query the pixel with stored in the metadata. This
might differ from the width of image that is available through
gexiv2_metadata_get_pixel_width().
unstable since: 0.16.0
gexiv2_metadata_get_pixel_height
Get the actual unoriented display height in pixels of the loaded image. This may
be different than the height reported by various metadata tags, i.e. Exif.Photo.PixelYDimension.
gexiv2_metadata_get_pixel_width
Get the actual unoriented display width in pixels of the loaded
image. May be different than the width reported by various metadata tags, i.e. Exif.Photo.PixelXDimension.
gexiv2_metadata_get_preview_properties
An image may have stored one or more previews, often of different qualities, sometimes of
different image formats than the containing image. This call returns the properties of all
previews Exiv2 finds within the loaded image. Use gexiv2_metadata_get_preview_image() to
load a particular preview into memory.
gexiv2_metadata_get_supports_exif
Query whether the currently loaded image supports writing of EXIF metadata.
gexiv2_metadata_get_supports_iptc
Query whether the currently loaded image supports writing of IPTC metadata.
gexiv2_metadata_get_supports_xmp
Query whether the currently loaded image supports writing of XMP metadata.
gexiv2_metadata_get_tag_interpreted_string
An interpreted string is one fit for user display. It may display units or use formatting appropriate to the type of data the tag holds.
unstable since: 0.16.0
gexiv2_metadata_get_tag_long
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_get_tag_multiple
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_get_tag_raw
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_get_tag_string
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_get_xmp_packet
Get the currently encoded XMP packet (after having called gexiv2_metadata_try_get_xmp_packet()).
unstable since: 0.16.0
gexiv2_metadata_save_external
Saves the metadata to the specified using an XMP sidecar file.
since: 0.10.6
gexiv2_metadata_save_file
Saves the metadata to the specified file by reading the file into memory, copying this object’s metadata into the image, then writing the image back out.
gexiv2_metadata_set_comment
This is a composite setter that will set a number of fields to the supplied value. See
gexiv2_metadata_get_comment() for more information.
unstable since: 0.16.0
gexiv2_metadata_set_exif_tag_rational
Set EXIF tag represented by a fraction, with nom being the numerator,
den the denominator of the fraction.
unstable since: 0.16.0
gexiv2_metadata_set_exif_thumbnail_from_buffer
Sets or replaces the EXIF thumbnail with the data in buffer.
unstable since: 0.16.0
gexiv2_metadata_set_exif_thumbnail_from_file
Sets or replaces the EXIF thumbnail with the image in the file.
gexiv2_metadata_set_gps_info
Convenience function to create a new set of simple GPS data. Warning: Will remove any other
GPS information that is currently set. See gexiv2_metadata_update_gps_info() for
just modifying the GPS data.
unstable since: 0.16.0
gexiv2_metadata_set_metadata_pixel_height
Update the image’s metadata with height.
unstable since: 0.16.0
gexiv2_metadata_set_metadata_pixel_width
Composite setter to update the image’s metadata with width.
unstable since: 0.16.0
gexiv2_metadata_set_orientation
The orientation must be valid and cannot be GEXIV2_ORIENTATION_UNSPECIFIED.
unstable since: 0.16.0
gexiv2_metadata_set_tag_long
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_set_tag_multiple
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
gexiv2_metadata_set_tag_string
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_set_xmp_tag_struct
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
unstable since: 0.16.0
gexiv2_metadata_tag_supports_multiple_values
Check whether a tag supports multiple values.
unstable since: 0.16.0
gexiv2_metadata_try_clear_tag
Removes the Exiv2 tag from the metadata object.
deprecated: 0.14.0 since: 0.14.0
gexiv2_metadata_try_delete_gps_info
Removes all GPS metadata from the loaded image.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_erase_exif_thumbnail
Removes the EXIF thumbnail from the loaded image.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_generate_xmp_packet
Encode the XMP packet as a NULL-terminated string.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_comment
A composite accessor that uses the first available metadata field from a list of well-known locations to find the photo’s comment (or description).
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_exif_tag_rational
Fetch EXIF tag represented by a fraction. nom will contain the numerator,
den the denominator of the fraction on successful return.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_exposure_time
Returns the exposure time in seconds (shutter speed, not date-time of exposure) as a rational. See https://en.wikipedia.org/wiki/Shutter_speed for more information.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_fnumber
See https://en.wikipedia.org/wiki/F-number for more information. If Exif.Photo.FNumber does not exist, it will fall back to calculating the FNumber from Exif.Photo.ApertureValue (if available);.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_focal_length
See https://en.wikipedia.org/wiki/Flange_focal_distance for more information.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_gps_altitude
Convenience function to query the altitude stored in the GPS tags of the image.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_gps_info
Convenience function to query all available GPS information at once.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_gps_latitude
Query the latitude stored in the GPS tags of self.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_gps_longitude
Query the longitude stored in the GPS tags of self.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_iso_speed
See https://en.wikipedia.org/wiki/Iso_speed for more information.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_metadata_pixel_height
Composite accessor to query the pixel with stored in the metadata. This
might differ from the height of image that is available through
gexiv2_metadata_get_pixel_height().
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_metadata_pixel_width
Composite accessor to query the pixel with stored in the metadata. This
might differ from the width of image that is available through
gexiv2_metadata_get_pixel_width().
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_preview_image
Get a preview image from the metadata.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_get_tag_interpreted_string
An interpreted string is one fit for user display. It may display units or use formatting appropriate to the type of data the tag holds.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_tag_long
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.12.2 since: 0.12.2
gexiv2_metadata_try_get_tag_multiple
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_tag_raw
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_tag_string
Get a string representationf a tag.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_get_xmp_packet
Get the currently encoded XMP packet (after having called gexiv2_metadata_try_generate_xmp_packet()).
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_has_tag
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_comment
This is a composite setter that will set a number of fields to the supplied value. See
gexiv2_metadata_get_comment() for more information.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_exif_tag_rational
Set EXIF tag represented by a fraction, with nom being the numerator,
den the denominator of the fraction.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_set_exif_thumbnail_from_buffer
Sets or replaces the EXIF thumbnail with the data in buffer.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_gps_info
Convenience function to create a new set of simple GPS data. Warning: Will remove any other
GPS information that is currently set. See gexiv2_metadata_update_gps_info() for
just modifying the GPS data.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_set_metadata_pixel_height
Update the image’s metadata with height.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_metadata_pixel_width
Composite setter to update the image’s metadata with width.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_orientation
The orientation must be valid and cannot be [enum@GExiv2.Orientation.UNSPECIFIED.
deprecated: 0.16.0 since: 0.14.0
gexiv2_metadata_try_set_tag_long
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_set_tag_multiple
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_set_tag_string
Set the value of a tag using a string.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_set_xmp_tag_struct
The Exiv2 Tag Reference can be found at http://exiv2.org/metadata.html.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_try_tag_supports_multiple_values
Check whether a tag supports multiple values.
deprecated: 0.16.0. since: 0.14.0
gexiv2_metadata_try_update_gps_info
Convenience function to update longitude, latitude and altitude at once.
deprecated: 0.16.0 since: 0.12.2
gexiv2_metadata_update_gps_info
Convenience function to update longitude, latitude and altitude at once.
unstable since: 0.16.0
Signals
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.