File size: 11,368 Bytes
38f004a
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275

import numpy as np
import torch
from torch import nn
import math
from typing import Any, Callable, Optional, Tuple, Union
from torch.cuda.amp import autocast, GradScaler

from .vits_config import VitsConfig,VitsPreTrainedModel
from .flow import VitsResidualCouplingBlock
from .duration_predictor import VitsDurationPredictor, VitsStochasticDurationPredictor
from .encoder import VitsTextEncoder
from .decoder import VitsHifiGan
from .posterior_encoder import VitsPosteriorEncoder
from .discriminator import VitsDiscriminator
from .vits_output import VitsModelOutput, VitsTrainingOutput


class Vits_models_only_decoder(VitsPreTrainedModel):

    def __init__(self, config: VitsConfig):
        super().__init__(config)

        self.config = config
        self.text_encoder = VitsTextEncoder(config)
        self.flow = VitsResidualCouplingBlock(config)
        self.decoder = VitsHifiGan(config)



        if config.use_stochastic_duration_prediction:
            self.duration_predictor = VitsStochasticDurationPredictor(config)
        else:
            self.duration_predictor = VitsDurationPredictor(config)

        if config.num_speakers > 1:
            self.embed_speaker = nn.Embedding(config.num_speakers, config.speaker_embedding_size)

        # This is used only for training.
        self.posterior_encoder = VitsPosteriorEncoder(config)
        self.discriminator = VitsDiscriminator(config)

        # These parameters control the synthesised speech properties
        self.speaking_rate = config.speaking_rate
        self.noise_scale = config.noise_scale
        self.noise_scale_duration = config.noise_scale_duration
        self.segment_size = self.config.segment_size // self.config.hop_length

        # Initialize weights and apply final processing
        self.post_init()


    #....................................

    def monotonic_align_max_path(self,log_likelihoods, mask):
        # used for training - awfully slow
        # an alternative is proposed in examples/pytorch/text-to-speech/run_vits_finetuning.py
        path = torch.zeros_like(log_likelihoods)

        text_length_maxs = mask.sum(1)[:, 0]
        latent_length_maxs = mask.sum(2)[:, 0]

        indexes = latent_length_maxs - 1

        max_neg_val = -1e9

        for batch_id in range(len(path)):
            index = int(indexes[batch_id].item())
            text_length_max = int(text_length_maxs[batch_id].item())
            latent_length_max = int(latent_length_maxs[batch_id].item())

            for y in range(text_length_max):
                for x in range(max(0, latent_length_max + y - text_length_max), min(latent_length_max, y + 1)):
                    if x == y:
                        v_cur = max_neg_val
                    else:
                        v_cur = log_likelihoods[batch_id, y - 1, x]
                    if x == 0:
                        if y == 0:
                            v_prev = 0.0
                        else:
                            v_prev = max_neg_val
                    else:
                        v_prev = log_likelihoods[batch_id, y - 1, x - 1]
                    log_likelihoods[batch_id, y, x] += max(v_prev, v_cur)

            for y in range(text_length_max - 1, -1, -1):
                path[batch_id, y, index] = 1
                if index != 0 and (
                    index == y or log_likelihoods[batch_id, y - 1, index] < log_likelihoods[batch_id, y - 1, index - 1]
                ):
                    index = index - 1
        return path

    #....................................

    def slice_segments(self,hidden_states, ids_str, segment_size=4):

        batch_size, channels, _ = hidden_states.shape
        # 1d tensor containing the indices to keep
        indices = torch.arange(segment_size).to(ids_str.device)
        # extend the indices to match the shape of hidden_states
        indices = indices.view(1, 1, -1).expand(batch_size, channels, -1)
        # offset indices with ids_str
        indices = indices + ids_str.view(-1, 1, 1)
        # gather indices
        output = torch.gather(hidden_states, dim=2, index=indices)

        return output


    #....................................


    def rand_slice_segments(self,hidden_states, sample_lengths=None, segment_size=4):

        batch_size, _, seq_len = hidden_states.size()
        if sample_lengths is None:
            sample_lengths = seq_len
        ids_str_max = sample_lengths - segment_size + 1
        ids_str = (torch.rand([batch_size]).to(device=hidden_states.device) * ids_str_max).to(dtype=torch.long)
        ret = self.slice_segments(hidden_states, ids_str, segment_size)

        return ret, ids_str

    #....................................

    def resize_speaker_embeddings(

        self,

        new_num_speakers: int,

        speaker_embedding_size: Optional[int] = None,

        pad_to_multiple_of: Optional[int] = 2,

    ):
        if pad_to_multiple_of is not None:
            new_num_speakers = ((new_num_speakers + pad_to_multiple_of - 1) // pad_to_multiple_of) * pad_to_multiple_of

        # first, take care of embed_speaker
        if self.config.num_speakers <= 1:
            if speaker_embedding_size is None:
                raise ValueError(
                    "The current model had no previous speaker embedding, but `speaker_embedding_size` is not specified. Pass `speaker_embedding_size` to this method."
                )
            # create new embedding layer
            new_embeddings = nn.Embedding(
                new_num_speakers,
                speaker_embedding_size,
                device=self.device,
            )
            # initialize all new embeddings
            self._init_weights(new_embeddings)
        else:
            new_embeddings = self._get_resized_embeddings(self.embed_speaker, new_num_speakers)

        self.embed_speaker = new_embeddings

        # then take care of sub-models
        self.flow.resize_speaker_embeddings(speaker_embedding_size)
        for flow in self.flow.flows:
            self._init_weights(flow.wavenet.cond_layer)

        self.decoder.resize_speaker_embedding(speaker_embedding_size)
        self._init_weights(self.decoder.cond)

        self.duration_predictor.resize_speaker_embeddings(speaker_embedding_size)
        self._init_weights(self.duration_predictor.cond)

        self.posterior_encoder.resize_speaker_embeddings(speaker_embedding_size)
        self._init_weights(self.posterior_encoder.wavenet.cond_layer)

        self.config.num_speakers = new_num_speakers
        self.config.speaker_embedding_size = speaker_embedding_size

    #....................................

    def get_input_embeddings(self):
        return self.text_encoder.get_input_embeddings()

    #....................................

    def set_input_embeddings(self, value):
        self.text_encoder.set_input_embeddings(value)

    #....................................

    def apply_weight_norm(self):
        self.decoder.apply_weight_norm()
        self.flow.apply_weight_norm()
        self.posterior_encoder.apply_weight_norm()

    #....................................

    def remove_weight_norm(self):
        self.decoder.remove_weight_norm()
        self.flow.remove_weight_norm()
        self.posterior_encoder.remove_weight_norm()

    #....................................

    def discriminate(self, hidden_states):
        return self.discriminator(hidden_states)

    #....................................

    def get_encoder(self):
        return self.text_encoder

    #....................................

    def _inference_forward(

        self,

        input_ids: Optional[torch.Tensor] = None,

        attention_mask: Optional[torch.Tensor] = None,

        speaker_embeddings: Optional[torch.Tensor] = None,

        output_attentions: Optional[bool] = None,

        output_hidden_states: Optional[bool] = None,

        return_dict: Optional[bool] = None,

        padding_mask: Optional[torch.Tensor] = None,

    ):
        text_encoder_output = self.text_encoder(
            input_ids=input_ids,
            padding_mask=padding_mask,
            attention_mask=attention_mask,
            output_attentions=output_attentions,
            output_hidden_states=output_hidden_states,
            return_dict=return_dict,
        )
        hidden_states = text_encoder_output[0] if not return_dict else text_encoder_output.last_hidden_state
        hidden_states = hidden_states.transpose(1, 2)
        input_padding_mask = padding_mask.transpose(1, 2)

        prior_means = text_encoder_output[1] if not return_dict else text_encoder_output.prior_means
        prior_log_variances = text_encoder_output[2] if not return_dict else text_encoder_output.prior_log_variances

        if self.config.use_stochastic_duration_prediction:
            log_duration = self.duration_predictor(
                hidden_states,
                input_padding_mask,
                speaker_embeddings,
                reverse=True,
                noise_scale=self.noise_scale_duration,
            )
        else:
            log_duration = self.duration_predictor(hidden_states, input_padding_mask, speaker_embeddings)

        length_scale = 1.0 / self.speaking_rate
        duration = torch.ceil(torch.exp(log_duration) * input_padding_mask * length_scale)
        predicted_lengths = torch.clamp_min(torch.sum(duration, [1, 2]), 1).long()


        # Create a padding mask for the output lengths of shape (batch, 1, max_output_length)
        indices = torch.arange(predicted_lengths.max(), dtype=predicted_lengths.dtype, device=predicted_lengths.device)
        output_padding_mask = indices.unsqueeze(0) < predicted_lengths.unsqueeze(1)
        output_padding_mask = output_padding_mask.unsqueeze(1).to(input_padding_mask.dtype)

        # Reconstruct an attention tensor of shape (batch, 1, out_length, in_length)
        attn_mask = torch.unsqueeze(input_padding_mask, 2) * torch.unsqueeze(output_padding_mask, -1)
        batch_size, _, output_length, input_length = attn_mask.shape
        cum_duration = torch.cumsum(duration, -1).view(batch_size * input_length, 1)
        indices = torch.arange(output_length, dtype=duration.dtype, device=duration.device)
        valid_indices = indices.unsqueeze(0) < cum_duration
        valid_indices = valid_indices.to(attn_mask.dtype).view(batch_size, input_length, output_length)
        padded_indices = valid_indices - nn.functional.pad(valid_indices, [0, 0, 1, 0, 0, 0])[:, :-1]
        attn = padded_indices.unsqueeze(1).transpose(2, 3) * attn_mask

        # Expand prior distribution
        prior_means = torch.matmul(attn.squeeze(1), prior_means).transpose(1, 2)
        prior_log_variances = torch.matmul(attn.squeeze(1), prior_log_variances).transpose(1, 2)

        prior_latents = prior_means + torch.randn_like(prior_means) * torch.exp(prior_log_variances) * self.noise_scale
        latents = self.flow(prior_latents, output_padding_mask, speaker_embeddings, reverse=True)

        spectrogram = latents * output_padding_mask
        return spectrogram