def get_slic_points_labels(segm, img=None, slic_size=20, slic_regul=0.1):
""" run SLIC on image or supepixels and return superpixels, their centers
and also lebels (label from segmentation in position of superpixel centre)
:param ndarray segm:
:param ndarray img:
:param int slic_size: superpixel size
:param float slic_regul: regularisation in range (0, 1)
:return:
"""
if img is None:
img = segm / float(segm.max())
slic = seg_spx.segment_slic_img2d(img, sp_size=slic_size,
rltv_compact=slic_regul)
slic_centers = np.array(seg_spx.superpixel_centers(slic)).astype(int)
labels = segm[slic_centers[:, 0], slic_centers[:, 1]]
return slic, slic_centers, labels
def insert_gc_debug_images(dict_debug_imgs, segments, graph_labels, unary_cost,
edges, edge_weights):
""" wrapper for placing intermediate variable to a dictionary """
if dict_debug_imgs is None:
return
dict_debug_imgs['segments'] = segments
dict_debug_imgs['edges'] = edges
dict_debug_imgs['edge_weights'] = edge_weights
dict_debug_imgs['imgs_unary_cost'] = \
tl_visu.draw_graphcut_unary_cost_segments(segments, unary_cost)
img = dict_debug_imgs.get('slic_mean', None)
list_centres = seg_spx.superpixel_centers(segments)
dict_debug_imgs['img_graph_edges'] = \
tl_visu.draw_graphcut_weighted_edges(segments, list_centres, edges,
edge_weights, img_bg=img)
dict_debug_imgs['img_graph_segm'] = \
tl_visu.draw_color_labeling(segments, graph_labels)
def estim_points_compute_features(name, img, segm, params):
""" determine points (center candidates) using slic
and for each compute feature vector with their names
:param str name:
:param ndarray img:
:param ndarray segm:
:param {str: any} params:
:return str, np.array, [(int, int)], [[float]], [str]:
"""
# superpixels on image
assert img.shape[:2] == segm.shape[:2], \
'shapes: %s : %s' % (repr(img.shape), repr(segm.shape))
slic = seg_spx.segment_slic_img2d(img, params['slic_size'],
params['slic_regul'])
slic_centers = seg_spx.superpixel_centers(slic)
# slic_edges = seg_spx.make_graph_segm_connect2d_conn4(slic)
features, feature_names = compute_points_features(segm, slic_centers,
params)
return name, slic, slic_centers, features, feature_names
def filter_boundary_points(segm, slic):
slic_centers = np.array(seg_spx.superpixel_centers(slic)).astype(int)
labels = segm[slic_centers[:, 0], slic_centers[:, 1]]
vertices, edges = seg_spx.make_graph_segm_connect2d_conn4(slic)
nb_labels = labels.max() + 1
neighbour_labels = np.zeros((len(vertices), nb_labels))
for e1, e2 in edges:
# print e1, labels[e2], e2, labels[e1]
neighbour_labels[e1, labels[e2]] += 1
neighbour_labels[e2, labels[e1]] += 1
neighbour_labels = neighbour_labels \
/ np.tile(np.sum(neighbour_labels, axis=1),
(nb_labels, 1)).T
# border point nex to foreground
filter_bg = np.logical_and(labels == 0, neighbour_labels[:, 0] < 1)
# fulucul cels next to backround
filter_fc = np.logical_and(labels == 1, neighbour_labels[:, 0] > 0)
points = slic_centers[np.logical_or(filter_bg, filter_fc)]
return points
def compute_edge_weights(segments,
image=None,
features=None,
proba=None,
edge_type=''):
"""
pp 32, http://www.coe.utah.edu/~cs7640/readings/graph_cuts_intro.pdf
exp(- norm value diff) * (geom dist vertex)**-1
:param ndarry segments: superpixels
:param ndarry image: input image
:param ndarry features: features for each segment (superpixel)
:param ndarry proba: probability of each superpixel and class
:param str edge_type: contains edge type, if 'model', after '_' you can
specify the metric, eg. 'model_l2'
:return [[int, int]], [float]:
>>> segments = np.array([[0] * 3 + [1] * 5 + [2] * 4,
... [4] * 4 + [5] * 5 + [6] * 3])
>>> np.random.seed(0)
>>> img = np.random.random(segments.shape + (3,)) * 255
>>> features = np.random.random((segments.max() + 1, 15)) * 10
>>> proba = np.random.random((segments.max() + 1, 2))
>>> edges, weights = compute_edge_weights(segments)
>>> edges.tolist()
[[0, 1], [1, 2], [0, 4], [1, 4], [1, 5], [2, 5], [4, 5], [2, 6], [5, 6]]
>>> np.round(weights, 2).tolist()
[1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0]
>>> edges, weights = compute_edge_weights(segments, image=img,
... edge_type='spatial')
>>> np.round(weights, 3).tolist()
[0.776, 0.69, 2.776, 0.853, 2.194, 0.853, 0.69, 2.776, 0.776]
>>> edges, weights = compute_edge_weights(segments, image=img,
... edge_type='color')
>>> np.round(weights, 3).tolist()
[0.06, 0.002, 0.0, 0.0, 0.0, 0.009, 0.0, 0.019, 0.044]
>>> edges, weights = compute_edge_weights(segments, features=features,
... edge_type='features')
>>> np.round(weights, 3).tolist()
[0.031, 0.005, 0.051, 0.032, 0.096, 0.013, 0.018, 0.033, 0.013]
>>> edges, weights = compute_edge_weights(segments, proba=proba,
... edge_type='model')
>>> np.round(weights, 3).tolist()
[0.0, 0.028, 1.122, 0.038, 0.117, 0.688, 0.487, 1.152, 0.282]
"""
logging.debug('extraction segment connectivity...')
_, edges = get_vertexes_edges(segments)
# convert variables
edges = np.array(edges, dtype=np.int32)
logging.debug('graph edges %s', repr(edges.shape))
if edge_type.startswith('model'):
assert proba is not None
metric = edge_type.split('_')[-1] if '_' in edge_type else 'lT'
edge_weights = compute_edge_model(edges, proba, metric)
elif edge_type == 'color':
assert image is not None
# {'color': ['mean', 'median']}
image_float = np.array(image, dtype=float)
if np.max(image) > 1:
image_float /= 255.
color, _ = seg_fts.compute_selected_features_img2d(
image_float, segments, {'color': ['mean']})
vertex_1 = color[edges[:, 0]]
vertex_2 = color[edges[:, 1]]
dist = metrics.pairwise.paired_manhattan_distances(vertex_1, vertex_2)
weights = dist.astype(float) / (2 * np.std(dist)**2)
edge_weights = np.exp(-weights)
elif edge_type == 'features':
assert features is not None
features_norm = preprocessing.StandardScaler().fit_transform(features)
vertex_1 = features_norm[edges[:, 0]]
vertex_2 = features_norm[edges[:, 1]]
dist = metrics.pairwise.paired_euclidean_distances(vertex_1, vertex_2)
weights = dist.astype(float) / (2 * np.std(dist)**2)
edge_weights = np.exp(-weights)
else:
edge_weights = np.ones(len(edges))
edge_weights = np.array(edge_weights, dtype=float)
if edge_type in ['model', 'features', 'color', 'spatial']:
centres = seg_spx.superpixel_centers(segments)
spatial = compute_spatial_dist(centres, edges, relative=True)
edge_weights /= spatial
return edges, edge_weights