RasterSource

class RasterSource

Bases: ABC

A source of raster data.

This should be subclassed when adding a new source of raster data such as a set of files, an API, a TMS URI schema, etc.

Attributes

crs_transformer	Associated CRSTransformer.
dtype	numpy.dtype of the chips read from this source.
extent	Extent of the RasterSource.
num_channels	Number of channels in the chips read from this source.
shape	Shape of the raster as a (height, width, num_channels) tuple.

__init__(channel_order: Optional[List[int]], num_channels_raw: int, raster_transformers: List[RasterTransformer] = [], extent: Optional[Box] = None)

Constructor.

Parameters

• channel_order (Optional[List[int]]) – list of channel indices to use when extracting chip from raw imagery.

• num_channels_raw (int) – Number of channels in the raw imagery before applying channel_order.

• raster_transformers (List[RasterTransformer]) – RasterTransformers for transforming chips whenever they are retrieved. Defaults to [].

• extent (Optional[Box]) – Use-specified extent. If None, the full extent of the raster source is used.

Methods

__init__(channel_order, num_channels_raw[, ...])	Constructor.
get_chip(window)	Return the transformed chip in the window.
get_image_array()	Return entire transformed image array.
get_raw_chip(window)	Return raw chip without applying channel_order or transforms.
get_raw_image_array()	Return raw image for the full extent.

__init__(channel_order: Optional[List[int]], num_channels_raw: int, raster_transformers: List[RasterTransformer] = [], extent: Optional[Box] = None)

Constructor.

Parameters

• channel_order (Optional[List[int]]) – list of channel indices to use when extracting chip from raw imagery.

• num_channels_raw (int) – Number of channels in the raw imagery before applying channel_order.

• raster_transformers (List[RasterTransformer]) – RasterTransformers for transforming chips whenever they are retrieved. Defaults to [].

• extent (Optional[Box]) – Use-specified extent. If None, the full extent of the raster source is used.

get_chip(window: Box) → np.ndarray

Return the transformed chip in the window.

Get a raw chip, extract subset of channels using channel_order, and then apply transformations.

Parameters

window (Box) – The window for which to get the chip.

Returns

Array of shape (height, width, channels).

Return type

np.ndarray

get_image_array() → np.ndarray

Return entire transformed image array.

Warning

Not safe to call on very large RasterSources.

Returns

Array of shape (height, width, channels).

Return type

np.ndarray

get_raw_chip(window: Box) → np.ndarray

Return raw chip without applying channel_order or transforms.

Parameters

window (Box) – The window for which to get the chip.

Returns

Array of shape (height, width, channels).

Return type

np.ndarray

get_raw_image_array() → np.ndarray

Return raw image for the full extent.

Warning

Not safe to call on very large RasterSources.

Returns

Array of shape (height, width, channels).

Return type

np.ndarray

abstract property crs_transformer: CRSTransformer

Associated CRSTransformer.

abstract property dtype: np.dtype

numpy.dtype of the chips read from this source.

property extent: Box

Extent of the RasterSource.

property num_channels: int

Number of channels in the chips read from this source.

property shape: Tuple[int, int, int]

Shape of the raster as a (height, width, num_channels) tuple.