Annotation¶

tiatoolbox . annotation . storage . Annotation

class Annotation(geometry=None, properties=None, wkb=None)[source]¶

An annotation: a geometry and associated properties.

geometry¶

The geometry of the annotation as a Shapely object.

Type:: Geometry

properties¶

The properties of the annotation.

Type:: dict

wkb¶

The WKB representation of the geometry.

Type:: bytes

Create a new annotation.

Must be initialized with either a Shapely geometry object or WKB bytes.

Parameters:

geometry (Geometry) – The geometry of the annotation.
properties (dict) – The properties of the annotation. Optional, defaults to {}.
wkb (bytes) – The WKB representation of a geometry. Optional.

Methods

`decode_wkb`	Decode WKB to a NumPy array of flat (alternating x, y) coordinates.
`to_feature`	Return a feature representation of this annotation.
`to_geojson`	Return a GeoJSON string representation of this annotation.
`to_wkb`	Returns the geometry as Well-Known Binary (WKB).
`to_wkt`	Returns the geometry as Well-Know Text (WKT).

Attributes

`properties`
`coords`	The annotation geometry as a flat array of 2D coordinates.
`geometry`	Return the shapely geometry of the annotation.
`geometry_type`	Return the geometry type of the annotation.
`wkb`	Return the WKB representation of the annotation.

property coords: ndarray | list[ndarray] | list[list[ndarray]]¶

The annotation geometry as a flat array of 2D coordinates.

Returns a numpy array of coordinates for point and line string. For polygons, returns a list of numpy arrays, one for each ring. For multi-geometries, returns a list with one element for each geometry.

Returns:: The coordinates of the annotation geometry.
Return type:: np.array or list

static decode_wkb(wkb, geom_type)[source]¶

Decode WKB to a NumPy array of flat (alternating x, y) coordinates.

Polygons return a list of NumPy arrays (one array per ring) and multi-part geometries return a list with one element per child geometry e.g. a list of arrays for Multi-Line and a list of lists of arrays for multi-polyon.

Parameters:

wkb (bytes) – The WKB representation of a geometry.
geom_type (int) – The type of geometry to decode. Where 1 = point, 2 = line, 3 = polygon, 4 = multi-point, 5 = multi-line, 6 = multi-polygon.

Return type:

ndarray | list[ndarray] | list[list[ndarray]]

Examples

>>> from tiatoolbox.annotation.storage import AnnotationStore
>>> # Point(1, 2).wkb
>>> wkb = (
...     b"\x01\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00"
...     b"\xf0?\x00\x00\x00\x00\x00\x00\x00@"
... )
>>> AnnotationStore.decode_wkb(wkb, 1)
array([0., 0.])

>>> from tiatoolbox.annotation.storage import AnnotationStore
>>> # Polygon([[0, 0], [1, 1], [1, 0]]).wkb
>>> wkb = (
...     b"\x01\x03\x00\x00\x00\x01\x00\x00\x00\x04\x00\x00\x00"
...     b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
...     b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf0?\x00\x00\x00"
...     b"\x00\x00\x00\xf0?\x00\x00\x00\x00\x00\x00\xf0?\x00"
...     b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
...     b"\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
... )
>>> AnnotationStore.decode_wkb(wkb, 3)
array([[0., 0.],
    [1., 1.],
    [1., 0.],
    [0., 0.]])

Raises:

ValueError – If the geometry type is not supported.

Returns:

An array of coordinates, a list of coordinates, or a list of lists of coordinates.

Return type:

np.ndarray or list

Parameters:

wkb (bytes)
geom_type (int)

property geometry: Point | LineString | Polygon¶: Return the shapely geometry of the annotation.

property geometry_type: GeometryType¶: Return the geometry type of the annotation.

to_feature()[source]¶

Return a feature representation of this annotation.

A feature representation is a Python dictionary with the same schema as a geoJSON feature.

Returns:: A feature representation of this annotation.
Return type:: dict
Parameters:: self (Annotation)

to_geojson()[source]¶

Return a GeoJSON string representation of this annotation.

Returns:: A GeoJSON representation of this annotation.
Return type:: str
Parameters:: self (Annotation)

to_wkb()[source]¶

Returns the geometry as Well-Known Binary (WKB).

Returns:: The annotation as a WKB geometry.
Return type:: Annotation
Parameters:: self (Annotation)

to_wkt()[source]¶

Returns the geometry as Well-Know Text (WKT).

Returns:: The annotation as a WKT geometry.
Return type:: Annotation
Parameters:: self (Annotation)

property wkb: bytes¶: Return the WKB representation of the annotation.