Я не могу понять, что такое атрибут "count" в графе смежности регионов, вычисляемый следующей функцией: skimage.future.graph.rag_boundary().
Объясняется атрибут «вес», но не «счет».
Даже читая исходный код, я не понимал, что это такое. Кто-нибудь может мне помочь ? Спасибо
Вот источник:
def rag_boundary(labels, edge_map, connectivity=2):
""" Comouter RAG based on region boundaries
Given an image's initial segmentation and its edge map this method
constructs the corresponding Region Adjacency Graph (RAG). Each node in the
RAG represents a set of pixels within the image with the same label in
`labels`. The weight between two adjacent regions is the average value
in `edge_map` along their boundary.
labels : ndarray
The labelled image.
edge_map : ndarray
This should have the same shape as that of `labels`. For all pixels
along the boundary between 2 adjacent regions, the average value of the
corresponding pixels in `edge_map` is the edge weight between them.
connectivity : int, optional
Pixels with a squared distance less than `connectivity` from each other
are considered adjacent. It can range from 1 to `labels.ndim`. Its
behavior is the same as `connectivity` parameter in
`scipy.ndimage.filters.generate_binary_structure`.
Examples
--------
>>> from skimage import data, segmentation, filters, color
>>> from skimage.future import graph
>>> img = data.chelsea()
>>> labels = segmentation.slic(img)
>>> edge_map = filters.sobel(color.rgb2gray(img))
>>> rag = graph.rag_boundary(labels, edge_map)
"""
conn = ndi.generate_binary_structure(labels.ndim, connectivity)
eroded = ndi.grey_erosion(labels, footprint=conn)
dilated = ndi.grey_dilation(labels, footprint=conn)
boundaries0 = (eroded != labels)
boundaries1 = (dilated != labels)
labels_small = np.concatenate((eroded[boundaries0], labels[boundaries1]))
labels_large = np.concatenate((labels[boundaries0], dilated[boundaries1]))
n = np.max(labels_large) + 1
# use a dummy broadcast array as data for RAG
ones = as_strided(np.ones((1,), dtype=np.float), shape=labels_small.shape,
strides=(0,))
count_matrix = sparse.coo_matrix((ones, (labels_small, labels_large)),
dtype=np.int_, shape=(n, n)).tocsr()
data = np.concatenate((edge_map[boundaries0], edge_map[boundaries1]))
data_coo = sparse.coo_matrix((data, (labels_small, labels_large)))
graph_matrix = data_coo.tocsr()
graph_matrix.data /= count_matrix.data
rag = RAG()
rag.add_weighted_edges_from(_edge_generator_from_csr(graph_matrix),
weight='weight')
rag.add_weighted_edges_from(_edge_generator_from_csr(count_matrix),
weight='count')
for n in rag.nodes():
rag.node[n].update({'labels': [n]})
return rag