File size: 6,582 Bytes
108ccb4
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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

import torch
import torch.nn as nn
import torch.nn.functional as F
import math

class CNNPrenet(torch.nn.Module):
    def __init__(self):
        super(CNNPrenet, self).__init__()

        # Define the layers using Sequential container
        self.conv_layers = nn.Sequential(
            nn.Conv1d(in_channels=1, out_channels=512, kernel_size=3, padding=1),
            nn.BatchNorm1d(512),
            nn.ReLU(),
            nn.Dropout(0.1),

            nn.Conv1d(in_channels=512, out_channels=512, kernel_size=3, padding=1),
            nn.BatchNorm1d(512),
            nn.ReLU(),
            nn.Dropout(0.1),

            nn.Conv1d(in_channels=512, out_channels=512, kernel_size=3, padding=1),
            nn.BatchNorm1d(512),
            nn.ReLU(),
            nn.Dropout(0.1)
        )

    def forward(self, x):

        # Add a new dimension for the channel
        x = x.unsqueeze(1)

        # Pass input through convolutional layers
        x = self.conv_layers(x)

        # Remove the channel dimension
        x = x.squeeze(1)

        # Scale the output to the range [-1, 1]
        x = torch.tanh(x)

        return x



class CNNDecoderPrenet(nn.Module):
    def __init__(self, input_dim=80, hidden_dim=256, output_dim=256, final_dim=512, dropout_rate=0.5):
        super(CNNDecoderPrenet, self).__init__()
        self.layer1 = nn.Linear(input_dim, hidden_dim)
        self.layer2 = nn.Linear(hidden_dim, output_dim)
        self.linear_projection = nn.Linear(output_dim, final_dim) # Added linear projection
        self.dropout = nn.Dropout(dropout_rate)

    def forward(self, x):

      # Transpose the input tensor to have the feature dimension as the last dimension
      x = x.transpose(1, 2)
      # Apply the linear layers
      x = F.relu(self.layer1(x))
      x = self.dropout(x)
      x = F.relu(self.layer2(x))
      x = self.dropout(x)
      # Apply the linear projection
      x = self.linear_projection(x)
      x = x.transpose(1, 2)

      return x




class CNNPostNet(torch.nn.Module):
    """
    Conv Postnet
    Arguments
    ---------
    n_mel_channels: int
       input feature dimension for convolution layers
    postnet_embedding_dim: int
       output feature dimension for convolution layers
    postnet_kernel_size: int
       postnet convolution kernal size
    postnet_n_convolutions: int
       number of convolution layers
    postnet_dropout: float
        dropout probability fot postnet
    """

    def __init__(
        self,
        n_mel_channels=80,
        postnet_embedding_dim=512,
        postnet_kernel_size=5,
        postnet_n_convolutions=5,
        postnet_dropout=0.1,
    ):
        super(CNNPostNet, self).__init__()

        self.conv_pre = nn.Conv1d(
            in_channels=n_mel_channels,
            out_channels=postnet_embedding_dim,
            kernel_size=postnet_kernel_size,
            padding="same",
        )

        self.convs_intermedite = nn.ModuleList()
        for i in range(1, postnet_n_convolutions - 1):
            self.convs_intermedite.append(
                nn.Conv1d(
                    in_channels=postnet_embedding_dim,
                    out_channels=postnet_embedding_dim,
                    kernel_size=postnet_kernel_size,
                    padding="same",
                ),
            )

        self.conv_post = nn.Conv1d(
            in_channels=postnet_embedding_dim,
            out_channels=n_mel_channels,
            kernel_size=postnet_kernel_size,
            padding="same",
        )

        self.tanh = nn.Tanh()
        self.ln1 = nn.LayerNorm(postnet_embedding_dim)
        self.ln2 = nn.LayerNorm(postnet_embedding_dim)
        self.ln3 = nn.LayerNorm(n_mel_channels)
        self.dropout1 = nn.Dropout(postnet_dropout)
        self.dropout2 = nn.Dropout(postnet_dropout)
        self.dropout3 = nn.Dropout(postnet_dropout)


    def forward(self, x):
        """Computes the forward pass
        Arguments
        ---------
        x: torch.Tensor
            a (batch, time_steps, features) input tensor
        Returns
        -------
        output: torch.Tensor (the spectrogram predicted)
        """
        x = self.conv_pre(x)
        x = self.ln1(x.permute(0, 2, 1)).permute(0, 2, 1)  # Transpose to [batch_size, feature_dim, sequence_length]
        x = self.tanh(x)
        x = self.dropout1(x)

        for i in range(len(self.convs_intermedite)):
            x = self.convs_intermedite[i](x)
        x = self.ln2(x.permute(0, 2, 1)).permute(0, 2, 1)  # Transpose to [batch_size, feature_dim, sequence_length]
        x = self.tanh(x)
        x = self.dropout2(x)

        x = self.conv_post(x)
        x = self.ln3(x.permute(0, 2, 1)).permute(0, 2, 1)  # Transpose to [batch_size, feature_dim, sequence_length]
        x = self.dropout3(x)

        return x


class ScaledPositionalEncoding(nn.Module):
    """
    This class implements the absolute sinusoidal positional encoding function
    with an adaptive weight parameter alpha.

    PE(pos, 2i)   = sin(pos/(10000^(2i/dmodel)))
    PE(pos, 2i+1) = cos(pos/(10000^(2i/dmodel)))

    Arguments
    ---------
    input_size: int
        Embedding dimension.
    max_len : int, optional
        Max length of the input sequences (default 2500).
    Example
    -------
    >>> a = torch.rand((8, 120, 512))
    >>> enc = PositionalEncoding(input_size=a.shape[-1])
    >>> b = enc(a)
    >>> b.shape
    torch.Size([1, 120, 512])
    """

    def __init__(self, input_size, max_len=2500):
        super().__init__()
        if input_size % 2 != 0:
            raise ValueError(
                f"Cannot use sin/cos positional encoding with odd channels (got channels={input_size})"
            )
        self.max_len = max_len
        self.alpha = nn.Parameter(torch.ones(1))  # Define alpha as a trainable parameter
        pe = torch.zeros(self.max_len, input_size, requires_grad=False)
        positions = torch.arange(0, self.max_len).unsqueeze(1).float()
        denominator = torch.exp(
            torch.arange(0, input_size, 2).float()
            * -(math.log(10000.0) / input_size)
        )

        pe[:, 0::2] = torch.sin(positions * denominator)
        pe[:, 1::2] = torch.cos(positions * denominator)
        pe = pe.unsqueeze(0)
        self.register_buffer("pe", pe)

    def forward(self, x):
        """
        Arguments
        ---------
        x : tensor
            Input feature shape (batch, time, fea)
        """
        pe_scaled = self.pe[:, :x.size(1)].clone().detach() * self.alpha  # Scale positional encoding by alpha
        return pe_scaled