Exemplo n.º 1
0
def watershed_hierarchy_by_dynamics(graph, edge_weights, canonize_tree=True):
    """
    Watershed hierarchy by dynamics.

    The definition of hierarchical watershed follows the one given in:

        J. Cousty, L. Najman.
        `Incremental algorithm for hierarchical minimum spanning forests and saliency of watershed cuts <https://hal-upec-upem.archives-ouvertes.fr/hal-00622505/document>`_.
        ISMM 2011: 272-283.

    The algorithm used is described in:

        Laurent Najman, Jean Cousty, Benjamin Perret.
        `Playing with Kruskal: Algorithms for Morphological Trees in Edge-Weighted Graphs <https://hal.archives-ouvertes.fr/file/index/docid/798621/filename/ismm2013-algo.pdf>`_.
        ISMM 2013: 135-146.

    :param graph: input graph
    :param edge_weights: input graph edge weights
    :param canonize_tree: if ``True`` (default), the resulting hierarchy is canonized (see function :func:`~higra.canonize_hierarchy`),
           otherwise the returned hierarchy is a binary tree
    :return: a tree (Concept :class:`~higra.CptHierarchy` is ``True`` and :class:`~higra.CptBinaryHierarchy` otherwise)
             and its node altitudes
    """
    return watershed_hierarchy_by_attribute(
        graph, edge_weights, lambda tree, altitudes: hg.attribute_dynamics(
            tree, altitudes, "increasing"), canonize_tree)
Exemplo n.º 2
0
    def test_attribute_dynamics2(self):
        t = hg.Tree((11, 11, 9, 9, 8, 8, 13, 13, 10, 10, 12, 12, 14, 14, 14))
        altitudes = np.asarray((0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 1, 4, 8, 10.))
        ref = np.asarray((3, 3, 0, 0, 10, 10, 2, 2, 10, 0, 10, 3, 10, 2, 10))

        res = hg.attribute_dynamics(t, altitudes)
        self.assertTrue(np.all(res == ref))