Interface

GeglMetadata

Description

interface Gegl.Metadata : GObject.Object

No description available.

Prerequisite

In order to implement Metadata, your type must inherit fromGObject.

Implementations

Instance methods

gegl_metadata_get_resolution

Retrieve resolution from the application image metadata. Intended for use by the image file writer. If resolution is not supported by the application or if the operation fails FALSE is returned and the resolution values are not updated.

gegl_metadata_iter_get_value

Retrieve image file metadata from the application. Intended for use by the image file writer. If the operation fails it returns FALSE and value is not updated.

gegl_metadata_iter_init

Initialise an iterator to find all supported metadata keys.

gegl_metadata_iter_lookup

Look up the specified key and initialise an iterator to reference the associated metadata. The iterator is used in conjunction with gegl_metadata_set_value() and gegl_metadata_get_value(). Note that this iterator is not valid for gegl_metadata_iter_next().

gegl_metadata_iter_next

Move the iterator to the next metadata item.

gegl_metadata_iter_set_value

Set application data retrieved from image file’s metadata. Intended for use by the image file reader. If the operation fails it returns FALSE and value is ignored.

gegl_metadata_register_map

Set the name of the file module and pass an array of mappings from file-format specific metadata names to those used by Gegl. A GValue transformation function may be supplied, e.g. to parse or format timestamps.

gegl_metadata_set_resolution

Set resolution retrieved from image file’s metadata. Intended for use by the image file reader. If resolution is not supported by the application or if the operation fails FALSE is returned and the values are ignored.

gegl_metadata_unregister_map

Unregister the file module mappings and any further mappings added or modified by the application. This should be called after the file module completes operations.

Interface structure

struct GeglMetadataInterface {
  void (* register_map) (
    GeglMetadata* metadata,
    const gchar* file_module,
    guint flags,
    const GeglMetadataMap* map,
    gsize n_map
  );
  gboolean (* set_resolution) (
    GeglMetadata* metadata,
    GeglResolutionUnit unit,
    gfloat x,
    gfloat y
  );
  gboolean (* get_resolution) (
    GeglMetadata* metadata,
    GeglResolutionUnit* unit,
    gfloat* x,
    gfloat* y
  );
  gboolean (* iter_lookup) (
    GeglMetadata* metadata,
    GeglMetadataIter* iter,
    const gchar* key
  );
  void (* iter_init) (
    GeglMetadata* metadata,
    GeglMetadataIter* iter
  );
  const gchar* (* iter_next) (
    GeglMetadata* metadata,
    GeglMetadataIter* iter
  );
  gboolean (* iter_set_value) (
    GeglMetadata* metadata,
    GeglMetadataIter* iter,
    const GValue* value
  );
  gboolean (* iter_get_value) (
    GeglMetadata* metadata,
    GeglMetadataIter* iter,
    GValue* value
  );
  
}

The GeglMetadata interface structure.

Interface members

`register_map`	`void (* register_map) ( GeglMetadata* metadata, const gchar* file_module, guint flags, const GeglMetadataMap* map, gsize n_map )`
	No description available.
`set_resolution`	`gboolean (* set_resolution) ( GeglMetadata* metadata, GeglResolutionUnit unit, gfloat x, gfloat y )`
	No description available.
`get_resolution`	`gboolean (* get_resolution) ( GeglMetadata* metadata, GeglResolutionUnit* unit, gfloat* x, gfloat* y )`
	No description available.
`iter_lookup`	`gboolean (* iter_lookup) ( GeglMetadata* metadata, GeglMetadataIter* iter, const gchar* key )`
	No description available.
`iter_init`	`void (* iter_init) ( GeglMetadata* metadata, GeglMetadataIter* iter )`
	No description available.
`iter_next`	`const gchar* (* iter_next) ( GeglMetadata* metadata, GeglMetadataIter* iter )`
	No description available.
`iter_set_value`	`gboolean (* iter_set_value) ( GeglMetadata* metadata, GeglMetadataIter* iter, const GValue* value )`
	No description available.
`iter_get_value`	`gboolean (* iter_get_value) ( GeglMetadata* metadata, GeglMetadataIter* iter, GValue* value )`
	No description available.

Virtual methods

Gegl.Metadata.get_resolution