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# Copyright (c) 2022 SpeechBrain Authors. All Rights Reserved.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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"""
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This script contains basic functions used for speaker diarization.
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This script has an optional dependency on open source sklearn library.
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A few sklearn functions are modified in this script as per requirement.
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"""
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import argparse
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import warnings
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import numpy as np
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import scipy
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import sklearn
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from distutils.util import strtobool
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from scipy import sparse
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from scipy.sparse.csgraph import connected_components
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from scipy.sparse.csgraph import laplacian as csgraph_laplacian
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from scipy.sparse.linalg import eigsh
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from sklearn.cluster import SpectralClustering
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from sklearn.cluster._kmeans import k_means
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from sklearn.neighbors import kneighbors_graph
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def _graph_connected_component(graph, node_id):
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"""
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Find the largest graph connected components that contains one
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given node.
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Arguments
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---------
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graph : array-like, shape: (n_samples, n_samples)
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Adjacency matrix of the graph, non-zero weight means an edge
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between the nodes.
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node_id : int
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The index of the query node of the graph.
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Returns
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-------
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connected_components_matrix : array-like
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shape - (n_samples,).
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An array of bool value indicating the indexes of the nodes belonging
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to the largest connected components of the given query node.
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"""
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n_node = graph.shape[0]
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if sparse.issparse(graph):
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# speed up row-wise access to boolean connection mask
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graph = graph.tocsr()
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connected_nodes = np.zeros(n_node, dtype=bool)
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nodes_to_explore = np.zeros(n_node, dtype=bool)
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nodes_to_explore[node_id] = True
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for _ in range(n_node):
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last_num_component = connected_nodes.sum()
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np.logical_or(connected_nodes, nodes_to_explore, out=connected_nodes)
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if last_num_component >= connected_nodes.sum():
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break
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indices = np.where(nodes_to_explore)[0]
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nodes_to_explore.fill(False)
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for i in indices:
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if sparse.issparse(graph):
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neighbors = graph[i].toarray().ravel()
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else:
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neighbors = graph[i]
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np.logical_or(nodes_to_explore, neighbors, out=nodes_to_explore)
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return connected_nodes
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def _graph_is_connected(graph):
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"""
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Return whether the graph is connected (True) or Not (False)
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Arguments
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---------
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graph : array-like or sparse matrix, shape: (n_samples, n_samples)
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Adjacency matrix of the graph, non-zero weight means an edge between the nodes.
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Returns
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-------
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is_connected : bool
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True means the graph is fully connected and False means not.
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"""
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if sparse.isspmatrix(graph):
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# sparse graph, find all the connected components
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n_connected_components, _ = connected_components(graph)
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return n_connected_components == 1
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else:
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# dense graph, find all connected components start from node 0
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return _graph_connected_component(graph, 0).sum() == graph.shape[0]
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def _set_diag(laplacian, value, norm_laplacian):
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"""
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Set the diagonal of the laplacian matrix and convert it to a sparse
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format well suited for eigenvalue decomposition.
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Arguments
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---------
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laplacian : array or sparse matrix
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The graph laplacian.
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value : float
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The value of the diagonal.
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norm_laplacian : bool
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Whether the value of the diagonal should be changed or not.
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Returns
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-------
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laplacian : array or sparse matrix
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An array of matrix in a form that is well suited to fast eigenvalue
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decomposition, depending on the bandwidth of the matrix.
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"""
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n_nodes = laplacian.shape[0]
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# We need all entries in the diagonal to values
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if not sparse.isspmatrix(laplacian):
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if norm_laplacian:
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laplacian.flat[::n_nodes + 1] = value
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else:
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laplacian = laplacian.tocoo()
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if norm_laplacian:
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diag_idx = laplacian.row == laplacian.col
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laplacian.data[diag_idx] = value
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# If the matrix has a small number of diagonals (as in the
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# case of structured matrices coming from images), the
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# dia format might be best suited for matvec products:
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n_diags = np.unique(laplacian.row - laplacian.col).size
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if n_diags <= 7:
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# 3 or less outer diagonals on each side
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laplacian = laplacian.todia()
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else:
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# csr has the fastest matvec and is thus best suited to
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# arpack
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laplacian = laplacian.tocsr()
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return laplacian
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def _deterministic_vector_sign_flip(u):
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"""
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Modify the sign of vectors for reproducibility. Flips the sign of
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elements of all the vectors (rows of u) such that the absolute
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maximum element of each vector is positive.
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Arguments
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---------
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u : ndarray
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Array with vectors as its rows.
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Returns
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-------
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u_flipped : ndarray
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Array with the sign flipped vectors as its rows. The same shape as `u`.
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"""
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max_abs_rows = np.argmax(np.abs(u), axis=1)
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signs = np.sign(u[range(u.shape[0]), max_abs_rows])
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u *= signs[:, np.newaxis]
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return u
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def _check_random_state(seed):
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"""
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Turn seed into a np.random.RandomState instance.
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Arguments
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---------
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seed : None | int | instance of RandomState
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If seed is None, return the RandomState singleton used by np.random.
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If seed is an int, return a new RandomState instance seeded with seed.
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If seed is already a RandomState instance, return it.
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Otherwise raise ValueError.
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"""
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if seed is None or seed is np.random:
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return np.random.mtrand._rand
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if isinstance(seed, numbers.Integral):
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return np.random.RandomState(seed)
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if isinstance(seed, np.random.RandomState):
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return seed
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raise ValueError("%r cannot be used to seed a np.random.RandomState"
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" instance" % seed)
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def spectral_embedding(
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adjacency,
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n_components=8,
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norm_laplacian=True,
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drop_first=True, ):
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"""
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Returns spectral embeddings.
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Arguments
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---------
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adjacency : array-like or sparse graph
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shape - (n_samples, n_samples)
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The adjacency matrix of the graph to embed.
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n_components : int
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The dimension of the projection subspace.
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norm_laplacian : bool
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If True, then compute normalized Laplacian.
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drop_first : bool
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Whether to drop the first eigenvector.
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Returns
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-------
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embedding : array
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Spectral embeddings for each sample.
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Example
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-------
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>>> import numpy as np
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>>> import diarization as diar
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>>> affinity = np.array([[1, 1, 1, 0.5, 0, 0, 0, 0, 0, 0.5],
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... [1, 1, 1, 0, 0, 0, 0, 0, 0, 0],
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... [1, 1, 1, 0, 0, 0, 0, 0, 0, 0],
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... [0.5, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0.5, 0, 0, 0, 0, 0, 1, 1, 1, 1]])
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>>> embs = diar.spectral_embedding(affinity, 3)
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>>> # Notice similar embeddings
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>>> print(np.around(embs , decimals=3))
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[[ 0.075 0.244 0.285]
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[ 0.083 0.356 -0.203]
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[ 0.083 0.356 -0.203]
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[ 0.26 -0.149 0.154]
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[ 0.29 -0.218 -0.11 ]
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[ 0.29 -0.218 -0.11 ]
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[-0.198 -0.084 -0.122]
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[-0.198 -0.084 -0.122]
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[-0.198 -0.084 -0.122]
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[-0.167 -0.044 0.316]]
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"""
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# Whether to drop the first eigenvector
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if drop_first:
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n_components = n_components + 1
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if not _graph_is_connected(adjacency):
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warnings.warn("Graph is not fully connected, spectral embedding"
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" may not work as expected.")
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laplacian, dd = csgraph_laplacian(
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adjacency, normed=norm_laplacian, return_diag=True)
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laplacian = _set_diag(laplacian, 1, norm_laplacian)
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laplacian *= -1
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vals, diffusion_map = eigsh(
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laplacian,
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k=n_components,
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sigma=1.0,
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which="LM", )
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embedding = diffusion_map.T[n_components::-1]
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if norm_laplacian:
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embedding = embedding / dd
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embedding = _deterministic_vector_sign_flip(embedding)
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if drop_first:
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return embedding[1:n_components].T
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else:
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return embedding[:n_components].T
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def spectral_clustering(
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affinity,
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n_clusters=8,
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n_components=None,
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random_state=None,
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n_init=10, ):
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"""
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Performs spectral clustering.
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Arguments
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---------
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affinity : matrix
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Affinity matrix.
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n_clusters : int
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Number of clusters for kmeans.
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n_components : int
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Number of components to retain while estimating spectral embeddings.
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random_state : int
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A pseudo random number generator used by kmeans.
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n_init : int
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Number of time the k-means algorithm will be run with different centroid seeds.
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Returns
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-------
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labels : array
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Cluster label for each sample.
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Example
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-------
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>>> import numpy as np
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>>> diarization as diar
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>>> affinity = np.array([[1, 1, 1, 0.5, 0, 0, 0, 0, 0, 0.5],
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... [1, 1, 1, 0, 0, 0, 0, 0, 0, 0],
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... [1, 1, 1, 0, 0, 0, 0, 0, 0, 0],
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... [0.5, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 1, 1, 1, 0, 0, 0, 0],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0, 0, 0, 0, 0, 0, 1, 1, 1, 1],
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... [0.5, 0, 0, 0, 0, 0, 1, 1, 1, 1]])
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>>> labs = diar.spectral_clustering(affinity, 3)
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>>> # print (labs) # [2 2 2 1 1 1 0 0 0 0]
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"""
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random_state = _check_random_state(random_state)
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n_components = n_clusters if n_components is None else n_components
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maps = spectral_embedding(
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affinity,
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n_components=n_components,
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drop_first=False, )
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_, labels, _ = k_means(
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maps, n_clusters, random_state=random_state, n_init=n_init)
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return labels
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class EmbeddingMeta:
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"""
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A utility class to pack deep embeddings and meta-information in one object.
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Arguments
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---------
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segset : list
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List of session IDs as an array of strings.
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stats : tensor
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An ndarray of float64. Each line contains embedding
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from the corresponding session.
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"""
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def __init__(
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self,
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segset=None,
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stats=None, ):
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if segset is None:
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self.segset = numpy.empty(0, dtype="|O")
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self.stats = numpy.array([], dtype=np.float64)
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else:
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self.segset = segset
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self.stats = stats
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def norm_stats(self):
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"""
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Divide all first-order statistics by their Euclidean norm.
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"""
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vect_norm = np.clip(np.linalg.norm(self.stats, axis=1), 1e-08, np.inf)
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self.stats = (self.stats.transpose() / vect_norm).transpose()
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class SpecClustUnorm:
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"""
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This class implements the spectral clustering with unnormalized affinity matrix.
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Useful when affinity matrix is based on cosine similarities.
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Reference
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---------
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Von Luxburg, U. A tutorial on spectral clustering. Stat Comput 17, 395–416 (2007).
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https://doi.org/10.1007/s11222-007-9033-z
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Example
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-------
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>>> import diarization as diar
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>>> clust = diar.SpecClustUnorm(min_num_spkrs=2, max_num_spkrs=10)
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>>> emb = [[ 2.1, 3.1, 4.1, 4.2, 3.1],
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... [ 2.2, 3.1, 4.2, 4.2, 3.2],
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... [ 2.0, 3.0, 4.0, 4.1, 3.0],
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... [ 8.0, 7.0, 7.0, 8.1, 9.0],
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... [ 8.1, 7.1, 7.2, 8.1, 9.2],
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... [ 8.3, 7.4, 7.0, 8.4, 9.0],
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... [ 0.3, 0.4, 0.4, 0.5, 0.8],
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... [ 0.4, 0.3, 0.6, 0.7, 0.8],
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... [ 0.2, 0.3, 0.2, 0.3, 0.7],
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... [ 0.3, 0.4, 0.4, 0.4, 0.7],]
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>>> # Estimating similarity matrix
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>>> sim_mat = clust.get_sim_mat(emb)
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>>> print (np.around(sim_mat[5:,5:], decimals=3))
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[[1. 0.957 0.961 0.904 0.966]
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[0.957 1. 0.977 0.982 0.997]
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[0.961 0.977 1. 0.928 0.972]
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[0.904 0.982 0.928 1. 0.976]
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[0.966 0.997 0.972 0.976 1. ]]
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>>> # Prunning
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>>> prunned_sim_mat = clust.p_pruning(sim_mat, 0.3)
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>>> print (np.around(prunned_sim_mat[5:,5:], decimals=3))
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[[1. 0. 0. 0. 0. ]
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[0. 1. 0. 0.982 0.997]
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[0. 0.977 1. 0. 0.972]
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[0. 0.982 0. 1. 0.976]
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[0. 0.997 0. 0.976 1. ]]
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>>> # Symmetrization
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>>> sym_prund_sim_mat = 0.5 * (prunned_sim_mat + prunned_sim_mat.T)
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>>> print (np.around(sym_prund_sim_mat[5:,5:], decimals=3))
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[[1. 0. 0. 0. 0. ]
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[0. 1. 0.489 0.982 0.997]
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[0. 0.489 1. 0. 0.486]
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[0. 0.982 0. 1. 0.976]
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[0. 0.997 0.486 0.976 1. ]]
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>>> # Laplacian
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>>> laplacian = clust.get_laplacian(sym_prund_sim_mat)
|
|
|
>>> print (np.around(laplacian[5:,5:], decimals=3))
|
|
|
[[ 1.999 0. 0. 0. 0. ]
|
|
|
[ 0. 2.468 -0.489 -0.982 -0.997]
|
|
|
[ 0. -0.489 0.975 0. -0.486]
|
|
|
[ 0. -0.982 0. 1.958 -0.976]
|
|
|
[ 0. -0.997 -0.486 -0.976 2.458]]
|
|
|
>>> # Spectral Embeddings
|
|
|
>>> spec_emb, num_of_spk = clust.get_spec_embs(laplacian, 3)
|
|
|
>>> print(num_of_spk)
|
|
|
3
|
|
|
>>> # Clustering
|
|
|
>>> clust.cluster_embs(spec_emb, num_of_spk)
|
|
|
>>> # print (clust.labels_) # [0 0 0 2 2 2 1 1 1 1]
|
|
|
>>> # Complete spectral clustering
|
|
|
>>> clust.do_spec_clust(emb, k_oracle=3, p_val=0.3)
|
|
|
>>> # print(clust.labels_) # [0 0 0 2 2 2 1 1 1 1]
|
|
|
"""
|
|
|
|
|
|
def __init__(self, min_num_spkrs=2, max_num_spkrs=10):
|
|
|
|
|
|
self.min_num_spkrs = min_num_spkrs
|
|
|
self.max_num_spkrs = max_num_spkrs
|
|
|
|
|
|
def do_spec_clust(self, X, k_oracle, p_val):
|
|
|
"""
|
|
|
Function for spectral clustering.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
X : array
|
|
|
(n_samples, n_features).
|
|
|
Embeddings extracted from the model.
|
|
|
k_oracle : int
|
|
|
Number of speakers (when oracle number of speakers).
|
|
|
p_val : float
|
|
|
p percent value to prune the affinity matrix.
|
|
|
"""
|
|
|
|
|
|
# Similarity matrix computation
|
|
|
sim_mat = self.get_sim_mat(X)
|
|
|
|
|
|
# Refining similarity matrix with p_val
|
|
|
prunned_sim_mat = self.p_pruning(sim_mat, p_val)
|
|
|
|
|
|
# Symmetrization
|
|
|
sym_prund_sim_mat = 0.5 * (prunned_sim_mat + prunned_sim_mat.T)
|
|
|
|
|
|
# Laplacian calculation
|
|
|
laplacian = self.get_laplacian(sym_prund_sim_mat)
|
|
|
|
|
|
# Get Spectral Embeddings
|
|
|
emb, num_of_spk = self.get_spec_embs(laplacian, k_oracle)
|
|
|
|
|
|
# Perform clustering
|
|
|
self.cluster_embs(emb, num_of_spk)
|
|
|
|
|
|
def get_sim_mat(self, X):
|
|
|
"""
|
|
|
Returns the similarity matrix based on cosine similarities.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
X : array
|
|
|
(n_samples, n_features).
|
|
|
Embeddings extracted from the model.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
M : array
|
|
|
(n_samples, n_samples).
|
|
|
Similarity matrix with cosine similarities between each pair of embedding.
|
|
|
"""
|
|
|
|
|
|
# Cosine similarities
|
|
|
M = sklearn.metrics.pairwise.cosine_similarity(X, X)
|
|
|
return M
|
|
|
|
|
|
def p_pruning(self, A, pval):
|
|
|
"""
|
|
|
Refine the affinity matrix by zeroing less similar values.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
A : array
|
|
|
(n_samples, n_samples).
|
|
|
Affinity matrix.
|
|
|
pval : float
|
|
|
p-value to be retained in each row of the affinity matrix.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
A : array
|
|
|
(n_samples, n_samples).
|
|
|
Prunned affinity matrix based on p_val.
|
|
|
"""
|
|
|
|
|
|
n_elems = int((1 - pval) * A.shape[0])
|
|
|
|
|
|
# For each row in a affinity matrix
|
|
|
for i in range(A.shape[0]):
|
|
|
low_indexes = np.argsort(A[i, :])
|
|
|
low_indexes = low_indexes[0:n_elems]
|
|
|
|
|
|
# Replace smaller similarity values by 0s
|
|
|
A[i, low_indexes] = 0
|
|
|
|
|
|
return A
|
|
|
|
|
|
def get_laplacian(self, M):
|
|
|
"""
|
|
|
Returns the un-normalized laplacian for the given affinity matrix.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
M : array
|
|
|
(n_samples, n_samples)
|
|
|
Affinity matrix.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
L : array
|
|
|
(n_samples, n_samples)
|
|
|
Laplacian matrix.
|
|
|
"""
|
|
|
|
|
|
M[np.diag_indices(M.shape[0])] = 0
|
|
|
D = np.sum(np.abs(M), axis=1)
|
|
|
D = np.diag(D)
|
|
|
L = D - M
|
|
|
return L
|
|
|
|
|
|
def get_spec_embs(self, L, k_oracle=4):
|
|
|
"""
|
|
|
Returns spectral embeddings and estimates the number of speakers
|
|
|
using maximum Eigen gap.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
L : array (n_samples, n_samples)
|
|
|
Laplacian matrix.
|
|
|
k_oracle : int
|
|
|
Number of speakers when the condition is oracle number of speakers,
|
|
|
else None.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
emb : array (n_samples, n_components)
|
|
|
Spectral embedding for each sample with n Eigen components.
|
|
|
num_of_spk : int
|
|
|
Estimated number of speakers. If the condition is set to the oracle
|
|
|
number of speakers then returns k_oracle.
|
|
|
"""
|
|
|
|
|
|
lambdas, eig_vecs = scipy.linalg.eigh(L)
|
|
|
|
|
|
# if params["oracle_n_spkrs"] is True:
|
|
|
if k_oracle is not None:
|
|
|
num_of_spk = k_oracle
|
|
|
else:
|
|
|
lambda_gap_list = self.get_eigen_gaps(lambdas[1:self.max_num_spkrs])
|
|
|
|
|
|
num_of_spk = (np.argmax(
|
|
|
lambda_gap_list[:min(self.max_num_spkrs, len(lambda_gap_list))])
|
|
|
+ 2)
|
|
|
|
|
|
if num_of_spk < self.min_num_spkrs:
|
|
|
num_of_spk = self.min_num_spkrs
|
|
|
|
|
|
emb = eig_vecs[:, 0:num_of_spk]
|
|
|
|
|
|
return emb, num_of_spk
|
|
|
|
|
|
def cluster_embs(self, emb, k):
|
|
|
"""
|
|
|
Clusters the embeddings using kmeans.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
emb : array (n_samples, n_components)
|
|
|
Spectral embedding for each sample with n Eigen components.
|
|
|
k : int
|
|
|
Number of clusters to kmeans.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
self.labels_ : self
|
|
|
Labels for each sample embedding.
|
|
|
"""
|
|
|
_, self.labels_, _ = k_means(emb, k)
|
|
|
|
|
|
def get_eigen_gaps(self, eig_vals):
|
|
|
"""
|
|
|
Returns the difference (gaps) between the Eigen values.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
eig_vals : list
|
|
|
List of eigen values
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
eig_vals_gap_list : list
|
|
|
List of differences (gaps) between adjacent Eigen values.
|
|
|
"""
|
|
|
|
|
|
eig_vals_gap_list = []
|
|
|
for i in range(len(eig_vals) - 1):
|
|
|
gap = float(eig_vals[i + 1]) - float(eig_vals[i])
|
|
|
eig_vals_gap_list.append(gap)
|
|
|
|
|
|
return eig_vals_gap_list
|
|
|
|
|
|
|
|
|
class SpecCluster(SpectralClustering):
|
|
|
def perform_sc(self, X, n_neighbors=10):
|
|
|
"""
|
|
|
Performs spectral clustering using sklearn on embeddings.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
X : array (n_samples, n_features)
|
|
|
Embeddings to be clustered.
|
|
|
n_neighbors : int
|
|
|
Number of neighbors in estimating affinity matrix.
|
|
|
"""
|
|
|
|
|
|
# Computation of affinity matrix
|
|
|
connectivity = kneighbors_graph(
|
|
|
X,
|
|
|
n_neighbors=n_neighbors,
|
|
|
include_self=True, )
|
|
|
self.affinity_matrix_ = 0.5 * (connectivity + connectivity.T)
|
|
|
|
|
|
# Perform spectral clustering on affinity matrix
|
|
|
self.labels_ = spectral_clustering(
|
|
|
self.affinity_matrix_,
|
|
|
n_clusters=self.n_clusters, )
|
|
|
return self
|
|
|
|
|
|
|
|
|
def is_overlapped(end1, start2):
|
|
|
"""
|
|
|
Returns True if segments are overlapping.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
end1 : float
|
|
|
End time of the first segment.
|
|
|
start2 : float
|
|
|
Start time of the second segment.
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
overlapped : bool
|
|
|
True of segments overlapped else False.
|
|
|
|
|
|
Example
|
|
|
-------
|
|
|
>>> import diarization as diar
|
|
|
>>> diar.is_overlapped(5.5, 3.4)
|
|
|
True
|
|
|
>>> diar.is_overlapped(5.5, 6.4)
|
|
|
False
|
|
|
"""
|
|
|
|
|
|
if start2 > end1:
|
|
|
return False
|
|
|
else:
|
|
|
return True
|
|
|
|
|
|
|
|
|
def merge_ssegs_same_speaker(lol):
|
|
|
"""
|
|
|
Merge adjacent sub-segs from the same speaker.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
lol : list of list
|
|
|
Each list contains [rec_id, seg_start, seg_end, spkr_id].
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
new_lol : list of list
|
|
|
new_lol contains adjacent segments merged from the same speaker ID.
|
|
|
|
|
|
Example
|
|
|
-------
|
|
|
>>> import diarization as diar
|
|
|
>>> lol=[['r1', 5.5, 7.0, 's1'],
|
|
|
... ['r1', 6.5, 9.0, 's1'],
|
|
|
... ['r1', 8.0, 11.0, 's1'],
|
|
|
... ['r1', 11.5, 13.0, 's2'],
|
|
|
... ['r1', 14.0, 15.0, 's2'],
|
|
|
... ['r1', 14.5, 15.0, 's1']]
|
|
|
>>> diar.merge_ssegs_same_speaker(lol)
|
|
|
[['r1', 5.5, 11.0, 's1'], ['r1', 11.5, 13.0, 's2'], ['r1', 14.0, 15.0, 's2'], ['r1', 14.5, 15.0, 's1']]
|
|
|
"""
|
|
|
|
|
|
new_lol = []
|
|
|
|
|
|
# Start from the first sub-seg
|
|
|
sseg = lol[0]
|
|
|
flag = False
|
|
|
for i in range(1, len(lol)):
|
|
|
next_sseg = lol[i]
|
|
|
|
|
|
# IF sub-segments overlap AND has same speaker THEN merge
|
|
|
if is_overlapped(sseg[2], next_sseg[1]) and sseg[3] == next_sseg[3]:
|
|
|
sseg[2] = next_sseg[2] # just update the end time
|
|
|
# This is important. For the last sseg, if it is the same speaker the merge
|
|
|
# Make sure we don't append the last segment once more. Hence, set FLAG=True
|
|
|
if i == len(lol) - 1:
|
|
|
flag = True
|
|
|
new_lol.append(sseg)
|
|
|
else:
|
|
|
new_lol.append(sseg)
|
|
|
sseg = next_sseg
|
|
|
|
|
|
# Add last segment only when it was skipped earlier.
|
|
|
if flag is False:
|
|
|
new_lol.append(lol[-1])
|
|
|
|
|
|
return new_lol
|
|
|
|
|
|
|
|
|
def distribute_overlap(lol):
|
|
|
"""
|
|
|
Distributes the overlapped speech equally among the adjacent segments
|
|
|
with different speakers.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
lol : list of list
|
|
|
It has each list structure as [rec_id, seg_start, seg_end, spkr_id].
|
|
|
|
|
|
Returns
|
|
|
-------
|
|
|
new_lol : list of list
|
|
|
It contains the overlapped part equally divided among the adjacent
|
|
|
segments with different speaker IDs.
|
|
|
|
|
|
Example
|
|
|
-------
|
|
|
>>> import diarization as diar
|
|
|
>>> lol = [['r1', 5.5, 9.0, 's1'],
|
|
|
... ['r1', 8.0, 11.0, 's2'],
|
|
|
... ['r1', 11.5, 13.0, 's2'],
|
|
|
... ['r1', 12.0, 15.0, 's1']]
|
|
|
>>> diar.distribute_overlap(lol)
|
|
|
[['r1', 5.5, 8.5, 's1'], ['r1', 8.5, 11.0, 's2'], ['r1', 11.5, 12.5, 's2'], ['r1', 12.5, 15.0, 's1']]
|
|
|
"""
|
|
|
|
|
|
new_lol = []
|
|
|
sseg = lol[0]
|
|
|
|
|
|
# Add first sub-segment here to avoid error at: "if new_lol[-1] != sseg:" when new_lol is empty
|
|
|
# new_lol.append(sseg)
|
|
|
|
|
|
for i in range(1, len(lol)):
|
|
|
next_sseg = lol[i]
|
|
|
# No need to check if they are different speakers.
|
|
|
# Because if segments are overlapped then they always have different speakers.
|
|
|
# This is because similar speaker's adjacent sub-segments are already merged by "merge_ssegs_same_speaker()"
|
|
|
|
|
|
if is_overlapped(sseg[2], next_sseg[1]):
|
|
|
|
|
|
# Get overlap duration.
|
|
|
# Now this overlap will be divided equally between adjacent segments.
|
|
|
overlap = sseg[2] - next_sseg[1]
|
|
|
|
|
|
# Update end time of old seg
|
|
|
sseg[2] = sseg[2] - (overlap / 2.0)
|
|
|
|
|
|
# Update start time of next seg
|
|
|
next_sseg[1] = next_sseg[1] + (overlap / 2.0)
|
|
|
|
|
|
if len(new_lol) == 0:
|
|
|
# For first sub-segment entry
|
|
|
new_lol.append(sseg)
|
|
|
else:
|
|
|
# To avoid duplicate entries
|
|
|
if new_lol[-1] != sseg:
|
|
|
new_lol.append(sseg)
|
|
|
|
|
|
# Current sub-segment is next sub-segment
|
|
|
sseg = next_sseg
|
|
|
|
|
|
else:
|
|
|
# For the first sseg
|
|
|
if len(new_lol) == 0:
|
|
|
new_lol.append(sseg)
|
|
|
else:
|
|
|
# To avoid duplicate entries
|
|
|
if new_lol[-1] != sseg:
|
|
|
new_lol.append(sseg)
|
|
|
|
|
|
# Update the current sub-segment
|
|
|
sseg = next_sseg
|
|
|
|
|
|
# Add the remaining last sub-segment
|
|
|
new_lol.append(next_sseg)
|
|
|
|
|
|
return new_lol
|
|
|
|
|
|
|
|
|
def write_rttm(segs_list, out_rttm_file):
|
|
|
"""
|
|
|
Writes the segment list in RTTM format (A standard NIST format).
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
segs_list : list of list
|
|
|
Each list contains [rec_id, seg_start, seg_end, spkr_id].
|
|
|
out_rttm_file : str
|
|
|
Path of the output RTTM file.
|
|
|
"""
|
|
|
|
|
|
rttm = []
|
|
|
rec_id = segs_list[0][0]
|
|
|
|
|
|
for seg in segs_list:
|
|
|
new_row = [
|
|
|
"SPEAKER",
|
|
|
rec_id,
|
|
|
"0",
|
|
|
str(round(seg[1], 4)),
|
|
|
str(round(seg[2] - seg[1], 4)),
|
|
|
"<NA>",
|
|
|
"<NA>",
|
|
|
seg[3],
|
|
|
"<NA>",
|
|
|
"<NA>",
|
|
|
]
|
|
|
rttm.append(new_row)
|
|
|
|
|
|
with open(out_rttm_file, "w") as f:
|
|
|
for row in rttm:
|
|
|
line_str = " ".join(row)
|
|
|
f.write("%s\n" % line_str)
|
|
|
|
|
|
|
|
|
def do_AHC(diary_obj, out_rttm_file, rec_id, k_oracle=4, p_val=0.3):
|
|
|
"""
|
|
|
Performs Agglomerative Hierarchical Clustering on embeddings.
|
|
|
|
|
|
Arguments
|
|
|
---------
|
|
|
diary_obj : EmbeddingMeta type
|
|
|
Contains embeddings in diary_obj.stats and segment IDs in diary_obj.segset.
|
|
|
out_rttm_file : str
|
|
|
Path of the output RTTM file.
|
|
|
rec_id : str
|
|
|
Recording ID for the recording under processing.
|
|
|
k : int
|
|
|
Number of speaker (None, if it has to be estimated).
|
|
|
pval : float
|
|
|
`pval` for prunning affinity matrix. Used only when number of speakers
|
|
|
are unknown. Note that this is just for experiment. Prefer Spectral clustering
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for better clustering results.
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"""
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from sklearn.cluster import AgglomerativeClustering
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# p_val is the threshold_val (for AHC)
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diary_obj.norm_stats()
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# processing
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if k_oracle is not None:
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num_of_spk = k_oracle
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clustering = AgglomerativeClustering(
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n_clusters=num_of_spk,
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affinity="cosine",
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linkage="average", ).fit(diary_obj.stats)
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labels = clustering.labels_
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else:
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# Estimate num of using max eigen gap with `cos` affinity matrix.
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# This is just for experimentation.
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clustering = AgglomerativeClustering(
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n_clusters=None,
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affinity="cosine",
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linkage="average",
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distance_threshold=p_val, ).fit(diary_obj.stats)
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labels = clustering.labels_
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# Convert labels to speaker boundaries
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subseg_ids = diary_obj.segset
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lol = []
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for i in range(labels.shape[0]):
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spkr_id = rec_id + "_" + str(labels[i])
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sub_seg = subseg_ids[i]
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splitted = sub_seg.rsplit("_", 2)
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rec_id = str(splitted[0])
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sseg_start = float(splitted[1])
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sseg_end = float(splitted[2])
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a = [rec_id, sseg_start, sseg_end, spkr_id]
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lol.append(a)
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# Sorting based on start time of sub-segment
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lol.sort(key=lambda x: float(x[1]))
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# Merge and split in 2 simple steps: (i) Merge sseg of same speakers then (ii) split different speakers
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# Step 1: Merge adjacent sub-segments that belong to same speaker (or cluster)
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lol = merge_ssegs_same_speaker(lol)
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# Step 2: Distribute duration of adjacent overlapping sub-segments belonging to different speakers (or cluster)
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# Taking mid-point as the splitting time location.
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lol = distribute_overlap(lol)
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# logger.info("Completed diarizing " + rec_id)
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write_rttm(lol, out_rttm_file)
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def do_spec_clustering(diary_obj, out_rttm_file, rec_id, k, pval, affinity_type,
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n_neighbors):
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"""
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Performs spectral clustering on embeddings. This function calls specific
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clustering algorithms as per affinity.
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Arguments
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---------
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diary_obj : EmbeddingMeta type
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Contains embeddings in diary_obj.stats and segment IDs in diary_obj.segset.
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out_rttm_file : str
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Path of the output RTTM file.
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rec_id : str
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Recording ID for the recording under processing.
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k : int
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Number of speaker (None, if it has to be estimated).
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pval : float
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`pval` for prunning affinity matrix.
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affinity_type : str
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Type of similarity to be used to get affinity matrix (cos or nn).
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"""
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if affinity_type == "cos":
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clust_obj = SpecClustUnorm(min_num_spkrs=2, max_num_spkrs=10)
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k_oracle = k # use it only when oracle num of speakers
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clust_obj.do_spec_clust(diary_obj.stats, k_oracle, pval)
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labels = clust_obj.labels_
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else:
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clust_obj = SpecCluster(
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n_clusters=k,
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assign_labels="kmeans",
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random_state=1234,
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affinity="nearest_neighbors", )
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clust_obj.perform_sc(diary_obj.stats, n_neighbors)
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labels = clust_obj.labels_
|
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|
|
# Convert labels to speaker boundaries
|
|
|
subseg_ids = diary_obj.segset
|
|
|
lol = []
|
|
|
|
|
|
for i in range(labels.shape[0]):
|
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|
spkr_id = rec_id + "_" + str(labels[i])
|
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|
|
sub_seg = subseg_ids[i]
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|
|
splitted = sub_seg.rsplit("_", 2)
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|
|
rec_id = str(splitted[0])
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|
|
sseg_start = float(splitted[1])
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|
|
sseg_end = float(splitted[2])
|
|
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|
|
|
a = [rec_id, sseg_start, sseg_end, spkr_id]
|
|
|
lol.append(a)
|
|
|
|
|
|
# Sorting based on start time of sub-segment
|
|
|
lol.sort(key=lambda x: float(x[1]))
|
|
|
|
|
|
# Merge and split in 2 simple steps: (i) Merge sseg of same speakers then (ii) split different speakers
|
|
|
# Step 1: Merge adjacent sub-segments that belong to same speaker (or cluster)
|
|
|
lol = merge_ssegs_same_speaker(lol)
|
|
|
|
|
|
# Step 2: Distribute duration of adjacent overlapping sub-segments belonging to different speakers (or cluster)
|
|
|
# Taking mid-point as the splitting time location.
|
|
|
lol = distribute_overlap(lol)
|
|
|
|
|
|
# logger.info("Completed diarizing " + rec_id)
|
|
|
write_rttm(lol, out_rttm_file)
|
|
|
|
|
|
|
|
|
if __name__ == '__main__':
|
|
|
|
|
|
parser = argparse.ArgumentParser(
|
|
|
prog='python diarization.py --backend AHC', description='diarizing')
|
|
|
parser.add_argument(
|
|
|
'--sys_rttm_dir',
|
|
|
required=False,
|
|
|
help='Directory to store system RTTM files')
|
|
|
parser.add_argument(
|
|
|
'--ref_rttm_dir',
|
|
|
required=False,
|
|
|
help='Directory to store reference RTTM files')
|
|
|
parser.add_argument(
|
|
|
'--backend', default="AHC", help='type of backend, AHC or SC or kmeans')
|
|
|
parser.add_argument(
|
|
|
'--oracle_n_spkrs',
|
|
|
default=True,
|
|
|
type=strtobool,
|
|
|
help='Oracle num of speakers')
|
|
|
parser.add_argument(
|
|
|
'--mic_type',
|
|
|
default="Mix-Headset",
|
|
|
help='Type of microphone to be used')
|
|
|
parser.add_argument(
|
|
|
'--affinity', default="cos", help='affinity matrix, cos or nn')
|
|
|
parser.add_argument(
|
|
|
'--max_subseg_dur',
|
|
|
default=3.0,
|
|
|
type=float,
|
|
|
help='Duration in seconds of a subsegments to be prepared from larger segments'
|
|
|
)
|
|
|
parser.add_argument(
|
|
|
'--overlap',
|
|
|
default=1.5,
|
|
|
type=float,
|
|
|
help='Overlap duration in seconds between adjacent subsegments')
|
|
|
|
|
|
args = parser.parse_args()
|
|
|
|
|
|
pval = 0.3
|
|
|
rec_id = "utt0001"
|
|
|
n_neighbors = 10
|
|
|
out_rttm_file = "./out.rttm"
|
|
|
|
|
|
embeddings = np.empty(shape=[0, 32], dtype=np.float64)
|
|
|
segset = []
|
|
|
|
|
|
for i in range(10):
|
|
|
seg = [rec_id + "_" + str(i) + "_" + str(i + 1)]
|
|
|
segset = segset + seg
|
|
|
emb = np.random.rand(1, 32)
|
|
|
embeddings = np.concatenate((embeddings, emb), axis=0)
|
|
|
|
|
|
segset = np.array(segset, dtype="|O")
|
|
|
stat_obj = EmbeddingMeta(segset, embeddings)
|
|
|
if args.oracle_n_spkrs is True:
|
|
|
num_spkrs = 2
|
|
|
|
|
|
if args.backend == "SC":
|
|
|
print("begin SC ")
|
|
|
do_spec_clustering(
|
|
|
stat_obj,
|
|
|
out_rttm_file,
|
|
|
rec_id,
|
|
|
num_spkrs,
|
|
|
pval,
|
|
|
args.affinity,
|
|
|
n_neighbors, )
|
|
|
if args.backend == "AHC":
|
|
|
print("begin AHC ")
|
|
|
do_AHC(stat_obj, out_rttm_file, rec_id, num_spkrs, pval)
|
