io.tile

Grid commons module

gridr.io.tile.read_tile_edges(ds, ds_band, tile_shape, merge=False, window=None, check=True)[source]

Extracts the row and column edges of tiles within a specified window of a raster dataset.

This function identifies the boundary rows and columns of tiles (as defined by tile_shape) within a given window of a raster and reads the corresponding pixel values along those edges.

Parameters:

  • ds (rasterio.io.DatasetReader) – The open raster dataset to read from.

  • ds_band (int) – The band index (1-based) to read from the dataset.

  • tile_shape (Tuple[int, int]) – The shape of the tiles as (number of rows, number of columns) used to determine tile boundaries.

  • merge (bool, optional) – If True, tiles that are smaller than tile_shape at the edge are merged with the adjacent tile along the corresponding dimension. Defaults to False.

  • window (Optional[Window], optional) – A rasterio Window defining the region of the dataset to consider. The top-left corner of this window serves as the origin for tile alignment. If None, the full extent of the dataset is used. Defaults to None.

  • check (bool, optional) – If True, checks the consistency of the provided window against the dataset shape. Raises ValueError if the check fails. Defaults to True.

Return type:

Tuple[ndarray, ndarray, ndarray, ndarray]

Returns:

  • edge_row_indices (np.ndarray) – 1D array of global row indices corresponding to the horizontal edges of the tiles.

  • edge_col_indices (np.ndarray) – 1D array of global column indices corresponding to the vertical edges of the tiles.

  • edge_rows (np.ndarray) – 2D array containing the pixel values along each horizontal tile edge. Each row corresponds to a horizontal edge line.

  • edge_cols (np.ndarray) – 2D array containing the pixel values along each vertical tile edge. Each row corresponds to a vertical edge line.

Raises:

ValueError – If check is True and the provided window is not valid relative to the dataset.

Notes

  • The edge_rows array has shape (number of tile row edges, width of the window).

  • The edge_cols array has shape (number of tile column edges, height of the window).

  • The output arrays are allocated with order=’C’ for compatibility with downstream processing.