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Overview

async_geotiff.Overview dataclass

Bases: ReadMixin, FetchTileMixin, TransformMixin

An overview level of a Cloud-Optimized GeoTIFF image.

crs property 

crs: CRS

The coordinate reference system of the overview.

height property 

height: int

The height of the overview in pixels.

nodata property 

nodata: int | float | None

The nodata value for the overview, if any.

tile_height property 

tile_height: int

The height in pixels per tile of the overview.

tile_width property 

tile_width: int

The width in pixels per tile of the overview.

transform property 

transform: Affine

The affine transform mapping pixel coordinates to geographic coordinates.

Returns:

  • Affine ( Affine ) –

    The affine transform.

width property 

width: int

The width of the overview in pixels.

fetch_tiles async 

fetch_tiles(xy: Sequence[tuple[int, int]]) -> list[Tile]

Fetch multiple tiles from this overview.

Parameters:

index 

index(
    x: float, y: float, op: Callable[[float], int] = floor
) -> tuple[int, int]

Get the (row, col) index of the pixel containing (x, y).

Parameters:

  • x (float) –

    x value in coordinate reference system.

  • y (float) –

    y value in coordinate reference system.

  • op (Callable[[float], int], default: floor ) –

    Function to convert fractional pixels to whole numbers (floor, ceiling, round). Defaults to math.floor.

Returns:

read async 

read(*, window: Window | None = None) -> Array

Read pixel data for a window region.

This method fetches all tiles that intersect the given window and stitches them together, returning only the pixels within the window.

Parameters:

  • window (Window | None, default: None ) –

    A Window object defining the pixel region to read. If None, the entire image is read.

Returns:

  • Array –

    An Array containing the pixel data for the requested window.

Raises:

  • WindowError –

    If the window extends outside the image bounds.

xy 

xy(
    row: int,
    col: int,
    offset: Literal["center", "ul", "ur", "ll", "lr"] = "center",
) -> tuple[float, float]

Get the coordinates (x, y) of a pixel at (row, col).

The pixel's center is returned by default, but a corner can be returned by setting offset to one of "ul", "ur", "ll", "lr".

Parameters:

  • row (int) –

    Pixel row.

  • col (int) –

    Pixel column.

  • offset (Literal['center', 'ul', 'ur', 'll', 'lr'], default: 'center' ) –

    Determines if the returned coordinates are for the center of the pixel or for a corner.

Returns: