Module « scipy.ndimage »

Fonction distance_transform_bf - module scipy.ndimage

Signature de la fonction distance_transform_bf

def distance_transform_bf(input, metric='euclidean', sampling=None, return_distances=True, return_indices=False, distances=None, indices=None) 

Description

distance_transform_bf.__doc__

    Distance transform function by a brute force algorithm.

    This function calculates the distance transform of the `input`, by
    replacing each foreground (non-zero) element, with its
    shortest distance to the background (any zero-valued element).

    In addition to the distance transform, the feature transform can
    be calculated. In this case the index of the closest background
    element to each foreground element is returned in a separate array.

    Parameters
    ----------
    input : array_like
        Input
    metric : {'euclidean', 'taxicab', 'chessboard'}, optional
        'cityblock' and 'manhattan' are also valid, and map to 'taxicab'.
        The default is 'euclidean'.
    sampling : float, or sequence of float, optional
        This parameter is only used when `metric` is 'euclidean'.
        Spacing of elements along each dimension. If a sequence, must be of
        length equal to the input rank; if a single number, this is used for
        all axes. If not specified, a grid spacing of unity is implied.
    return_distances : bool, optional
        Whether to calculate the distance transform.
        Default is True.
    return_indices : bool, optional
        Whether to calculate the feature transform.
        Default is False.
    distances : ndarray, optional
        An output array to store the calculated distance transform, instead of
        returning it.
        `return_distances` must be True.
        It must be the same shape as `input`, and of type float64 if `metric`
        is 'euclidean', uint32 otherwise.
    indices : int32 ndarray, optional
        An output array to store the calculated feature transform, instead of
        returning it.
        `return_indicies` must be True.
        Its shape must be `(input.ndim,) + input.shape`.

    Returns
    -------
    distances : ndarray, optional
        The calculated distance transform. Returned only when
        `return_distances` is True and `distances` is not supplied.
        It will have the same shape as the input array.
    indices : int32 ndarray, optional
        The calculated feature transform. It has an input-shaped array for each
        dimension of the input. See distance_transform_edt documentation for an
        example.
        Returned only when `return_indices` is True and `indices` is not
        supplied.

    Notes
    -----
    This function employs a slow brute force algorithm, see also the
    function distance_transform_cdt for more efficient taxicab and
    chessboard algorithms.