File size: 9,349 Bytes
89a1ae3
 
 
04455e3
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
89a1ae3
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
import torch
from speechbrain.inference.interfaces import Pretrained

class AttentionMLP(torch.nn.Module):
    def __init__(self, input_dim, hidden_dim):
        super(AttentionMLP, self).__init__()
        self.layers = torch.nn.Sequential(
            torch.nn.Linear(input_dim, hidden_dim),
            torch.nn.ReLU(),
            torch.nn.Linear(hidden_dim, 1, bias=False),
        )

    def forward(self, x):
        x = self.layers(x)
        att_w = torch.nn.functional.softmax(x, dim=2)
        return att_w


class Discrete_EmbeddingLayer(torch.nn.Module):
    """This class handles embedding layers  for discrete tokens.

    Arguments
    ---------
    num_codebooks: int ,
        number of codebooks of the tokenizer.
    vocab_size : int,
        size of the dictionary of embeddings
    emb_dim: int ,
        the size of each embedding vector
    pad_index: int (default: 0),
        If specified, the entries at padding_idx do not contribute to the gradient.
    init: boolean (default: False):
        If set to True, init the embedding with the tokenizer embedding otherwise init randomly.
    freeze: boolean (default: False)
       If True, the embedding is frozen. If False, the model will be trained
        alongside with the rest of the pipeline.

    Example
    -------
    >>> from speechbrain.lobes.models.huggingface_transformers.encodec import Encodec
    >>> model_hub = "facebook/encodec_24khz"
    >>> save_path = "savedir"
    >>> model = Encodec(model_hub, save_path)
    >>> audio = torch.randn(4, 1000)
    >>> length = torch.tensor([1.0, .5, .75, 1.0])
    >>> tokens, emb = model.encode(audio, length)
    >>> print(tokens.shape)
    torch.Size([4, 4, 2])
    >>> emb= Discrete_EmbeddingLayer(2, 1024, 1024)
    >>> in_emb = emb(tokens)
    >>> print(in_emb.shape)
    torch.Size([4, 4, 2, 1024])
    """

    def __init__(
        self,
        num_codebooks,
        vocab_size,
        emb_dim,
        pad_index=0,
        init=False,
        freeze=False,
    ):
        super(Discrete_EmbeddingLayer, self).__init__()
        self.vocab_size = vocab_size
        self.num_codebooks = num_codebooks
        self.freeze = freeze
        self.embedding = torch.nn.Embedding(
            num_codebooks * vocab_size, emb_dim
        ).requires_grad_(not self.freeze)
        self.init = init

    def init_embedding(self, weights):
        with torch.no_grad():
            self.embedding.weight = torch.nn.Parameter(weights)

    def forward(self, in_tokens):
        """Computes the embedding for discrete tokens.
        a sample.

        Arguments
        ---------
        in_tokens : torch.Tensor
            A (Batch x Time x num_codebooks)
            audio sample
        Returns
        -------
        in_embs : torch.Tensor
        """
        with torch.set_grad_enabled(not self.freeze):
            #  Add unique token IDs across diffrent codebooks by adding num_codebooks * vocab_size
            in_tokens += torch.arange(
                0,
                self.num_codebooks * self.vocab_size,
                self.vocab_size,
                device=in_tokens.device,
            )
            # Forward Pass to embedding and
            in_embs = self.embedding(in_tokens)
            return in_embs

class CustomEncoderClassifier(Pretrained):
    """A ready-to-use class for utterance-level classification (e.g, speaker-id,
    language-id, emotion recognition, keyword spotting, etc).
    The class assumes that an self-supervised encoder like wav2vec2/hubert and a classifier model
    are defined in the yaml file. If you want to
    convert the predicted index into a corresponding text label, please
    provide the path of the label_encoder in a variable called 'lab_encoder_file'
    within the yaml.
    The class can be used either to run only the encoder (encode_batch()) to
    extract embeddings or to run a classification step (classify_batch()).
    ```
    Example
    -------
    >>> import torchaudio
    >>> from speechbrain.pretrained import EncoderClassifier
    >>> # Model is downloaded from the speechbrain HuggingFace repo
    >>> tmpdir = getfixture("tmpdir")
    >>> classifier = EncoderClassifier.from_hparams(
    ...     source="speechbrain/spkrec-ecapa-voxceleb",
    ...     savedir=tmpdir,
    ... )
    >>> # Compute embeddings
    >>> signal, fs = torchaudio.load("samples/audio_samples/example1.wav")
    >>> embeddings =  classifier.encode_batch(signal)
    >>> # Classification
    >>> prediction =  classifier .classify_batch(signal)
    """

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.similarity = torch.nn.CosineSimilarity(dim=-1, eps=1e-6)

    def encode_batch(self, wavs, wav_lens=None, normalize=False):
        """Encodes the input audio into a single vector embedding.
        The waveforms should already be in the model's desired format.
        You can call:
        ``normalized = <this>.normalizer(signal, sample_rate)``
        to get a correctly converted signal in most cases.
        Arguments
        ---------
        wavs : torch.tensor
            Batch of waveforms [batch, time, channels] or [batch, time]
            depending on the model. Make sure the sample rate is fs=16000 Hz.
        wav_lens : torch.tensor
            Lengths of the waveforms relative to the longest one in the
            batch, tensor of shape [batch]. The longest one should have
            relative length 1.0 and others len(waveform) / max_length.
            Used for ignoring padding.
        normalize : bool
            If True, it normalizes the embeddings with the statistics
            contained in mean_var_norm_emb.
        Returns
        -------
        torch.tensor
            The encoded batch
        """
        # Manage single waveforms in input
        if len(wavs.shape) == 1:
            wavs = wavs.unsqueeze(0)

        # Assign full length if wav_lens is not assigned
        if wav_lens is None:
            wav_lens = torch.ones(wavs.shape[0], device=self.device)

        # Storing waveform in the specified device
        wavs, wav_lens = wavs.to(self.device), wav_lens.to(self.device)
        wavs = wavs.float()

        with torch.no_grad():
            self.hparams.codec.to(self.device).eval()
            tokens, _, _ = self.hparams.codec(
                wavs, wav_lens, **self.hparams.tokenizer_config
            )
            embeddings = self.mods.discrete_embedding_layer(tokens)
            att_w = self.mods.attention_mlp(embeddings)
            feats = torch.matmul(att_w.transpose(2, -1), embeddings).squeeze(-2)
            embeddings = self.mods.embedding_model(feats, wav_lens)
        return embeddings.squeeze(1)


    def verify_batch(
        self, wavs1, wavs2, wav1_lens=None, wav2_lens=None, threshold=0.25
    ):
        """Performs speaker verification with cosine distance.

        It returns the score and the decision (0 different speakers,
        1 same speakers).

        Arguments
        ---------
        wavs1 : Torch.Tensor
            torch.Tensor containing the speech waveform1 (batch, time).
            Make sure the sample rate is fs=16000 Hz.
        wavs2 : Torch.Tensor
            torch.Tensor containing the speech waveform2 (batch, time).
            Make sure the sample rate is fs=16000 Hz.
        wav1_lens : Torch.Tensor
            torch.Tensor containing the relative length for each sentence
            in the length (e.g., [0.8 0.6 1.0])
        wav2_lens : Torch.Tensor
            torch.Tensor containing the relative length for each sentence
            in the length (e.g., [0.8 0.6 1.0])
        threshold : Float
            Threshold applied to the cosine distance to decide if the
            speaker is different (0) or the same (1).

        Returns
        -------
        score
            The score associated to the binary verification output
            (cosine distance).
        prediction
            The prediction is 1 if the two signals in input are from the same
            speaker and 0 otherwise.
        """
        emb1 = self.encode_batch(wavs1, wav1_lens, normalize=False)
        emb2 = self.encode_batch(wavs2, wav2_lens, normalize=False)
        score = self.similarity(emb1, emb2)
        return score, score > threshold

    def verify_files(self, path_x, path_y, **kwargs):
        """Speaker verification with cosine distance

        Returns the score and the decision (0 different speakers,
        1 same speakers).

        Arguments
        ---------
        path_x : str
            Path to file x
        path_y : str
            Path to file y
        **kwargs : dict
            Arguments to ``load_audio``

        Returns
        -------
        score
            The score associated to the binary verification output
            (cosine distance).
        prediction
            The prediction is 1 if the two signals in input are from the same
            speaker and 0 otherwise.
        """
        waveform_x = self.load_audio(path_x, **kwargs)
        waveform_y = self.load_audio(path_y, **kwargs)
        # Fake batches:
        batch_x = waveform_x.unsqueeze(0)
        batch_y = waveform_y.unsqueeze(0)
        # Verify:
        score, decision = self.verify_batch(batch_x, batch_y)
        # Squeeze:
        return score[0], decision[0]