goathead777/Zero_Shot_Inference
0
1import math2import numpy as np3import torch4from torch import nn5from torch.nn import functional as F6 7from torch.nn import Conv1d8from torch.nn.utils import weight_norm, remove_weight_norm9 10from module import commons11from module.commons import init_weights, get_padding12from module.transforms import piecewise_rational_quadratic_transform13import torch.distributions as D14 15 16LRELU_SLOPE = 0.117 18 19class LayerNorm(nn.Module):20 def __init__(self, channels, eps=1e-5):21 super().__init__()22 self.channels = channels23 self.eps = eps24 25 self.gamma = nn.Parameter(torch.ones(channels))26 self.beta = nn.Parameter(torch.zeros(channels))27 28 def forward(self, x):29 x = x.transpose(1, -1)30 x = F.layer_norm(x, (self.channels,), self.gamma, self.beta, self.eps)31 return x.transpose(1, -1)32 33 34class ConvReluNorm(nn.Module):35 def __init__(36 self,37 in_channels,38 hidden_channels,39 out_channels,40 kernel_size,41 n_layers,42 p_dropout,43 ):44 super().__init__()45 self.in_channels = in_channels46 self.hidden_channels = hidden_channels47 self.out_channels = out_channels48 self.kernel_size = kernel_size49 self.n_layers = n_layers50 self.p_dropout = p_dropout51 assert n_layers > 1, "Number of layers should be larger than 0."52 53 self.conv_layers = nn.ModuleList()54 self.norm_layers = nn.ModuleList()55 self.conv_layers.append(56 nn.Conv1d(57 in_channels, hidden_channels, kernel_size, padding=kernel_size // 258 )59 )60 self.norm_layers.append(LayerNorm(hidden_channels))61 self.relu_drop = nn.Sequential(nn.ReLU(), nn.Dropout(p_dropout))62 for _ in range(n_layers - 1):63 self.conv_layers.append(64 nn.Conv1d(65 hidden_channels,66 hidden_channels,67 kernel_size,68 padding=kernel_size // 2,69 )70 )71 self.norm_layers.append(LayerNorm(hidden_channels))72 self.proj = nn.Conv1d(hidden_channels, out_channels, 1)73 self.proj.weight.data.zero_()74 self.proj.bias.data.zero_()75 76 def forward(self, x, x_mask):77 x_org = x78 for i in range(self.n_layers):79 x = self.conv_layers[i](x * x_mask)80 x = self.norm_layers[i](x)81 x = self.relu_drop(x)82 x = x_org + self.proj(x)83 return x * x_mask84 85 86class DDSConv(nn.Module):87 """88 Dialted and Depth-Separable Convolution89 """90 91 def __init__(self, channels, kernel_size, n_layers, p_dropout=0.0):92 super().__init__()93 self.channels = channels94 self.kernel_size = kernel_size95 self.n_layers = n_layers96 self.p_dropout = p_dropout97 98 self.drop = nn.Dropout(p_dropout)99 self.convs_sep = nn.ModuleList()100 self.convs_1x1 = nn.ModuleList()101 self.norms_1 = nn.ModuleList()102 self.norms_2 = nn.ModuleList()103 for i in range(n_layers):104 dilation = kernel_size**i105 padding = (kernel_size * dilation - dilation) // 2106 self.convs_sep.append(107 nn.Conv1d(108 channels,109 channels,110 kernel_size,111 groups=channels,112 dilation=dilation,113 padding=padding,114 )115 )116 self.convs_1x1.append(nn.Conv1d(channels, channels, 1))117 self.norms_1.append(LayerNorm(channels))118 self.norms_2.append(LayerNorm(channels))119 120 def forward(self, x, x_mask, g=None):121 if g is not None:122 x = x + g123 for i in range(self.n_layers):124 y = self.convs_sep[i](x * x_mask)125 y = self.norms_1[i](y)126 y = F.gelu(y)127 y = self.convs_1x1[i](y)128 y = self.norms_2[i](y)129 y = F.gelu(y)130 y = self.drop(y)131 x = x + y132 return x * x_mask133 134 135class WN(torch.nn.Module):136 def __init__(137 self,138 hidden_channels,139 kernel_size,140 dilation_rate,141 n_layers,142 gin_channels=0,143 p_dropout=0,144 ):145 super(WN, self).__init__()146 assert kernel_size % 2 == 1147 self.hidden_channels = hidden_channels148 self.kernel_size = (kernel_size,)149 self.dilation_rate = dilation_rate150 self.n_layers = n_layers151 self.gin_channels = gin_channels152 self.p_dropout = p_dropout153 154 self.in_layers = torch.nn.ModuleList()155 self.res_skip_layers = torch.nn.ModuleList()156 self.drop = nn.Dropout(p_dropout)157 158 if gin_channels != 0:159 cond_layer = torch.nn.Conv1d(160 gin_channels, 2 * hidden_channels * n_layers, 1161 )162 self.cond_layer = torch.nn.utils.weight_norm(cond_layer, name="weight")163 164 for i in range(n_layers):165 dilation = dilation_rate**i166 padding = int((kernel_size * dilation - dilation) / 2)167 in_layer = torch.nn.Conv1d(168 hidden_channels,169 2 * hidden_channels,170 kernel_size,171 dilation=dilation,172 padding=padding,173 )174 in_layer = torch.nn.utils.weight_norm(in_layer, name="weight")175 self.in_layers.append(in_layer)176 177 # last one is not necessary178 if i < n_layers - 1:179 res_skip_channels = 2 * hidden_channels180 else:181 res_skip_channels = hidden_channels182 183 res_skip_layer = torch.nn.Conv1d(hidden_channels, res_skip_channels, 1)184 res_skip_layer = torch.nn.utils.weight_norm(res_skip_layer, name="weight")185 self.res_skip_layers.append(res_skip_layer)186 187 def forward(self, x, x_mask, g=None, **kwargs):188 output = torch.zeros_like(x)189 n_channels_tensor = torch.IntTensor([self.hidden_channels])190 191 if g is not None:192 g = self.cond_layer(g)193 194 for i in range(self.n_layers):195 x_in = self.in_layers[i](x)196 if g is not None:197 cond_offset = i * 2 * self.hidden_channels198 g_l = g[:, cond_offset : cond_offset + 2 * self.hidden_channels, :]199 else:200 g_l = torch.zeros_like(x_in)201 202 acts = commons.fused_add_tanh_sigmoid_multiply(x_in, g_l, n_channels_tensor)203 acts = self.drop(acts)204 205 res_skip_acts = self.res_skip_layers[i](acts)206 if i < self.n_layers - 1:207 res_acts = res_skip_acts[:, : self.hidden_channels, :]208 x = (x + res_acts) * x_mask209 output = output + res_skip_acts[:, self.hidden_channels :, :]210 else:211 output = output + res_skip_acts212 return output * x_mask213 214 def remove_weight_norm(self):215 if self.gin_channels != 0:216 torch.nn.utils.remove_weight_norm(self.cond_layer)217 for l in self.in_layers:218 torch.nn.utils.remove_weight_norm(l)219 for l in self.res_skip_layers:220 torch.nn.utils.remove_weight_norm(l)221 222 223class ResBlock1(torch.nn.Module):224 def __init__(self, channels, kernel_size=3, dilation=(1, 3, 5)):225 super(ResBlock1, self).__init__()226 self.convs1 = nn.ModuleList(227 [228 weight_norm(229 Conv1d(230 channels,231 channels,232 kernel_size,233 1,234 dilation=dilation[0],235 padding=get_padding(kernel_size, dilation[0]),236 )237 ),238 weight_norm(239 Conv1d(240 channels,241 channels,242 kernel_size,243 1,244 dilation=dilation[1],245 padding=get_padding(kernel_size, dilation[1]),246 )247 ),248 weight_norm(249 Conv1d(250 channels,251 channels,252 kernel_size,253 1,254 dilation=dilation[2],255 padding=get_padding(kernel_size, dilation[2]),256 )257 ),258 ]259 )260 self.convs1.apply(init_weights)261 262 self.convs2 = nn.ModuleList(263 [264 weight_norm(265 Conv1d(266 channels,267 channels,268 kernel_size,269 1,270 dilation=1,271 padding=get_padding(kernel_size, 1),272 )273 ),274 weight_norm(275 Conv1d(276 channels,277 channels,278 kernel_size,279 1,280 dilation=1,281 padding=get_padding(kernel_size, 1),282 )283 ),284 weight_norm(285 Conv1d(286 channels,287 channels,288 kernel_size,289 1,290 dilation=1,291 padding=get_padding(kernel_size, 1),292 )293 ),294 ]295 )296 self.convs2.apply(init_weights)297 298 def forward(self, x, x_mask=None):299 for c1, c2 in zip(self.convs1, self.convs2):300 xt = F.leaky_relu(x, LRELU_SLOPE)301 if x_mask is not None:302 xt = xt * x_mask303 xt = c1(xt)304 xt = F.leaky_relu(xt, LRELU_SLOPE)305 if x_mask is not None:306 xt = xt * x_mask307 xt = c2(xt)308 x = xt + x309 if x_mask is not None:310 x = x * x_mask311 return x312 313 def remove_weight_norm(self):314 for l in self.convs1:315 remove_weight_norm(l)316 for l in self.convs2:317 remove_weight_norm(l)318 319 320class ResBlock2(torch.nn.Module):321 def __init__(self, channels, kernel_size=3, dilation=(1, 3)):322 super(ResBlock2, self).__init__()323 self.convs = nn.ModuleList(324 [325 weight_norm(326 Conv1d(327 channels,328 channels,329 kernel_size,330 1,331 dilation=dilation[0],332 padding=get_padding(kernel_size, dilation[0]),333 )334 ),335 weight_norm(336 Conv1d(337 channels,338 channels,339 kernel_size,340 1,341 dilation=dilation[1],342 padding=get_padding(kernel_size, dilation[1]),343 )344 ),345 ]346 )347 self.convs.apply(init_weights)348 349 def forward(self, x, x_mask=None):350 for c in self.convs:351 xt = F.leaky_relu(x, LRELU_SLOPE)352 if x_mask is not None:353 xt = xt * x_mask354 xt = c(xt)355 x = xt + x356 if x_mask is not None:357 x = x * x_mask358 return x359 360 def remove_weight_norm(self):361 for l in self.convs:362 remove_weight_norm(l)363 364 365class Log(nn.Module):366 def forward(self, x, x_mask, reverse=False, **kwargs):367 if not reverse:368 y = torch.log(torch.clamp_min(x, 1e-5)) * x_mask369 logdet = torch.sum(-y, [1, 2])370 return y, logdet371 else:372 x = torch.exp(x) * x_mask373 return x374 375 376class Flip(nn.Module):377 def forward(self, x, *args, reverse=False, **kwargs):378 x = torch.flip(x, [1])379 if not reverse:380 logdet = torch.zeros(x.size(0)).to(dtype=x.dtype, device=x.device)381 return x, logdet382 else:383 return x384 385 386class ElementwiseAffine(nn.Module):387 def __init__(self, channels):388 super().__init__()389 self.channels = channels390 self.m = nn.Parameter(torch.zeros(channels, 1))391 self.logs = nn.Parameter(torch.zeros(channels, 1))392 393 def forward(self, x, x_mask, reverse=False, **kwargs):394 if not reverse:395 y = self.m + torch.exp(self.logs) * x396 y = y * x_mask397 logdet = torch.sum(self.logs * x_mask, [1, 2])398 return y, logdet399 else:400 x = (x - self.m) * torch.exp(-self.logs) * x_mask401 return x402 403 404class ResidualCouplingLayer(nn.Module):405 def __init__(406 self,407 channels,408 hidden_channels,409 kernel_size,410 dilation_rate,411 n_layers,412 p_dropout=0,413 gin_channels=0,414 mean_only=False,415 ):416 assert channels % 2 == 0, "channels should be divisible by 2"417 super().__init__()418 self.channels = channels419 self.hidden_channels = hidden_channels420 self.kernel_size = kernel_size421 self.dilation_rate = dilation_rate422 self.n_layers = n_layers423 self.half_channels = channels // 2424 self.mean_only = mean_only425 426 self.pre = nn.Conv1d(self.half_channels, hidden_channels, 1)427 self.enc = WN(428 hidden_channels,429 kernel_size,430 dilation_rate,431 n_layers,432 p_dropout=p_dropout,433 gin_channels=gin_channels,434 )435 self.post = nn.Conv1d(hidden_channels, self.half_channels * (2 - mean_only), 1)436 self.post.weight.data.zero_()437 self.post.bias.data.zero_()438 439 def forward(self, x, x_mask, g=None, reverse=False):440 x0, x1 = torch.split(x, [self.half_channels] * 2, 1)441 h = self.pre(x0) * x_mask442 h = self.enc(h, x_mask, g=g)443 stats = self.post(h) * x_mask444 if not self.mean_only:445 m, logs = torch.split(stats, [self.half_channels] * 2, 1)446 else:447 m = stats448 logs = torch.zeros_like(m)449 450 if not reverse:451 x1 = m + x1 * torch.exp(logs) * x_mask452 x = torch.cat([x0, x1], 1)453 logdet = torch.sum(logs, [1, 2])454 return x, logdet455 else:456 x1 = (x1 - m) * torch.exp(-logs) * x_mask457 x = torch.cat([x0, x1], 1)458 return x459 460 461class ConvFlow(nn.Module):462 def __init__(463 self,464 in_channels,465 filter_channels,466 kernel_size,467 n_layers,468 num_bins=10,469 tail_bound=5.0,470 ):471 super().__init__()472 self.in_channels = in_channels473 self.filter_channels = filter_channels474 self.kernel_size = kernel_size475 self.n_layers = n_layers476 self.num_bins = num_bins477 self.tail_bound = tail_bound478 self.half_channels = in_channels // 2479 480 self.pre = nn.Conv1d(self.half_channels, filter_channels, 1)481 self.convs = DDSConv(filter_channels, kernel_size, n_layers, p_dropout=0.0)482 self.proj = nn.Conv1d(483 filter_channels, self.half_channels * (num_bins * 3 - 1), 1484 )485 self.proj.weight.data.zero_()486 self.proj.bias.data.zero_()487 488 def forward(self, x, x_mask, g=None, reverse=False):489 x0, x1 = torch.split(x, [self.half_channels] * 2, 1)490 h = self.pre(x0)491 h = self.convs(h, x_mask, g=g)492 h = self.proj(h) * x_mask493 494 b, c, t = x0.shape495 h = h.reshape(b, c, -1, t).permute(0, 1, 3, 2) # [b, cx?, t] -> [b, c, t, ?]496 497 unnormalized_widths = h[..., : self.num_bins] / math.sqrt(self.filter_channels)498 unnormalized_heights = h[..., self.num_bins : 2 * self.num_bins] / math.sqrt(499 self.filter_channels500 )501 unnormalized_derivatives = h[..., 2 * self.num_bins :]502 503 x1, logabsdet = piecewise_rational_quadratic_transform(504 x1,505 unnormalized_widths,506 unnormalized_heights,507 unnormalized_derivatives,508 inverse=reverse,509 tails="linear",510 tail_bound=self.tail_bound,511 )512 513 x = torch.cat([x0, x1], 1) * x_mask514 logdet = torch.sum(logabsdet * x_mask, [1, 2])515 if not reverse:516 return x, logdet517 else:518 return x519 520 521class LinearNorm(nn.Module):522 def __init__(523 self,524 in_channels,525 out_channels,526 bias=True,527 spectral_norm=False,528 ):529 super(LinearNorm, self).__init__()530 self.fc = nn.Linear(in_channels, out_channels, bias)531 532 if spectral_norm:533 self.fc = nn.utils.spectral_norm(self.fc)534 535 def forward(self, input):536 out = self.fc(input)537 return out538 539 540class Mish(nn.Module):541 def __init__(self):542 super(Mish, self).__init__()543 544 def forward(self, x):545 return x * torch.tanh(F.softplus(x))546 547 548class Conv1dGLU(nn.Module):549 """550 Conv1d + GLU(Gated Linear Unit) with residual connection.551 For GLU refer to https://arxiv.org/abs/1612.08083 paper.552 """553 554 def __init__(self, in_channels, out_channels, kernel_size, dropout):555 super(Conv1dGLU, self).__init__()556 self.out_channels = out_channels557 self.conv1 = ConvNorm(in_channels, 2 * out_channels, kernel_size=kernel_size)558 self.dropout = nn.Dropout(dropout)559 560 def forward(self, x):561 residual = x562 x = self.conv1(x)563 x1, x2 = torch.split(x, split_size_or_sections=self.out_channels, dim=1)564 x = x1 * torch.sigmoid(x2)565 x = residual + self.dropout(x)566 return x567 568 569class ConvNorm(nn.Module):570 def __init__(571 self,572 in_channels,573 out_channels,574 kernel_size=1,575 stride=1,576 padding=None,577 dilation=1,578 bias=True,579 spectral_norm=False,580 ):581 super(ConvNorm, self).__init__()582 583 if padding is None:584 assert kernel_size % 2 == 1585 padding = int(dilation * (kernel_size - 1) / 2)586 587 self.conv = torch.nn.Conv1d(588 in_channels,589 out_channels,590 kernel_size=kernel_size,591 stride=stride,592 padding=padding,593 dilation=dilation,594 bias=bias,595 )596 597 if spectral_norm:598 self.conv = nn.utils.spectral_norm(self.conv)599 600 def forward(self, input):601 out = self.conv(input)602 return out603 604 605class MultiHeadAttention(nn.Module):606 """Multi-Head Attention module"""607 608 def __init__(self, n_head, d_model, d_k, d_v, dropout=0.0, spectral_norm=False):609 super().__init__()610 611 self.n_head = n_head612 self.d_k = d_k613 self.d_v = d_v614 615 self.w_qs = nn.Linear(d_model, n_head * d_k)616 self.w_ks = nn.Linear(d_model, n_head * d_k)617 self.w_vs = nn.Linear(d_model, n_head * d_v)618 619 self.attention = ScaledDotProductAttention(620 temperature=np.power(d_model, 0.5), dropout=dropout621 )622 623 self.fc = nn.Linear(n_head * d_v, d_model)624 self.dropout = nn.Dropout(dropout)625 626 if spectral_norm:627 self.w_qs = nn.utils.spectral_norm(self.w_qs)628 self.w_ks = nn.utils.spectral_norm(self.w_ks)629 self.w_vs = nn.utils.spectral_norm(self.w_vs)630 self.fc = nn.utils.spectral_norm(self.fc)631 632 def forward(self, x, mask=None):633 d_k, d_v, n_head = self.d_k, self.d_v, self.n_head634 sz_b, len_x, _ = x.size()635 636 residual = x637 638 q = self.w_qs(x).view(sz_b, len_x, n_head, d_k)639 k = self.w_ks(x).view(sz_b, len_x, n_head, d_k)640 v = self.w_vs(x).view(sz_b, len_x, n_head, d_v)641 q = q.permute(2, 0, 1, 3).contiguous().view(-1, len_x, d_k) # (n*b) x lq x dk642 k = k.permute(2, 0, 1, 3).contiguous().view(-1, len_x, d_k) # (n*b) x lk x dk643 v = v.permute(2, 0, 1, 3).contiguous().view(-1, len_x, d_v) # (n*b) x lv x dv644 645 if mask is not None:646 slf_mask = mask.repeat(n_head, 1, 1) # (n*b) x .. x ..647 else:648 slf_mask = None649 output, attn = self.attention(q, k, v, mask=slf_mask)650 651 output = output.view(n_head, sz_b, len_x, d_v)652 output = (653 output.permute(1, 2, 0, 3).contiguous().view(sz_b, len_x, -1)654 ) # b x lq x (n*dv)655 656 output = self.fc(output)657 658 output = self.dropout(output) + residual659 return output, attn660 661 662class ScaledDotProductAttention(nn.Module):663 """Scaled Dot-Product Attention"""664 665 def __init__(self, temperature, dropout):666 super().__init__()667 self.temperature = temperature668 self.softmax = nn.Softmax(dim=2)669 self.dropout = nn.Dropout(dropout)670 671 def forward(self, q, k, v, mask=None):672 attn = torch.bmm(q, k.transpose(1, 2))673 attn = attn / self.temperature674 675 if mask is not None:676 attn = attn.masked_fill(mask, -np.inf)677 678 attn = self.softmax(attn)679 p_attn = self.dropout(attn)680 681 output = torch.bmm(p_attn, v)682 return output, attn683 684 685class MelStyleEncoder(nn.Module):686 """MelStyleEncoder"""687 688 def __init__(689 self,690 n_mel_channels=80,691 style_hidden=128,692 style_vector_dim=256,693 style_kernel_size=5,694 style_head=2,695 dropout=0.1,696 ):697 super(MelStyleEncoder, self).__init__()698 self.in_dim = n_mel_channels699 self.hidden_dim = style_hidden700 self.out_dim = style_vector_dim701 self.kernel_size = style_kernel_size702 self.n_head = style_head703 self.dropout = dropout704 705 self.spectral = nn.Sequential(706 LinearNorm(self.in_dim, self.hidden_dim),707 Mish(),708 nn.Dropout(self.dropout),709 LinearNorm(self.hidden_dim, self.hidden_dim),710 Mish(),711 nn.Dropout(self.dropout),712 )713 714 self.temporal = nn.Sequential(715 Conv1dGLU(self.hidden_dim, self.hidden_dim, self.kernel_size, self.dropout),716 Conv1dGLU(self.hidden_dim, self.hidden_dim, self.kernel_size, self.dropout),717 )718 719 self.slf_attn = MultiHeadAttention(720 self.n_head,721 self.hidden_dim,722 self.hidden_dim // self.n_head,723 self.hidden_dim // self.n_head,724 self.dropout,725 )726 727 self.fc = LinearNorm(self.hidden_dim, self.out_dim)728 729 def temporal_avg_pool(self, x, mask=None):730 if mask is None:731 out = torch.mean(x, dim=1)732 else:733 len_ = (~mask).sum(dim=1).unsqueeze(1)734 x = x.masked_fill(mask.unsqueeze(-1), 0)735 x = x.sum(dim=1)736 out = torch.div(x, len_)737 return out738 739 def forward(self, x, mask=None):740 x = x.transpose(1, 2)741 if mask is not None:742 mask = (mask.int() == 0).squeeze(1)743 max_len = x.shape[1]744 slf_attn_mask = (745 mask.unsqueeze(1).expand(-1, max_len, -1) if mask is not None else None746 )747 748 # spectral749 x = self.spectral(x)750 # temporal751 x = x.transpose(1, 2)752 x = self.temporal(x)753 x = x.transpose(1, 2)754 # self-attention755 if mask is not None:756 x = x.masked_fill(mask.unsqueeze(-1), 0)757 x, _ = self.slf_attn(x, mask=slf_attn_mask)758 # fc759 x = self.fc(x)760 # temoral average pooling761 w = self.temporal_avg_pool(x, mask=mask)762 763 return w.unsqueeze(-1)764 765 766class MelStyleEncoderVAE(nn.Module):767 def __init__(self, spec_channels, z_latent_dim, emb_dim):768 super().__init__()769 self.ref_encoder = MelStyleEncoder(spec_channels, style_vector_dim=emb_dim)770 self.fc1 = nn.Linear(emb_dim, z_latent_dim)771 self.fc2 = nn.Linear(emb_dim, z_latent_dim)772 self.fc3 = nn.Linear(z_latent_dim, emb_dim)773 self.z_latent_dim = z_latent_dim774 775 def reparameterize(self, mu, logvar):776 if self.training:777 std = torch.exp(0.5 * logvar)778 eps = torch.randn_like(std)779 return eps.mul(std).add_(mu)780 else:781 return mu782 783 def forward(self, inputs, mask=None):784 enc_out = self.ref_encoder(inputs.squeeze(-1), mask).squeeze(-1)785 mu = self.fc1(enc_out)786 logvar = self.fc2(enc_out)787 posterior = D.Normal(mu, torch.exp(logvar))788 kl_divergence = D.kl_divergence(789 posterior, D.Normal(torch.zeros_like(mu), torch.ones_like(logvar))790 )791 loss_kl = kl_divergence.mean()792 793 z = posterior.rsample()794 style_embed = self.fc3(z)795 796 return style_embed.unsqueeze(-1), loss_kl797 798 def infer(self, inputs=None, random_sample=False, manual_latent=None):799 if manual_latent is None:800 if random_sample:801 dev = next(self.parameters()).device802 posterior = D.Normal(803 torch.zeros(1, self.z_latent_dim, device=dev),804 torch.ones(1, self.z_latent_dim, device=dev),805 )806 z = posterior.rsample()807 else:808 enc_out = self.ref_encoder(inputs.transpose(1, 2))809 mu = self.fc1(enc_out)810 z = mu811 else:812 z = manual_latent813 style_embed = self.fc3(z)814 return style_embed.unsqueeze(-1), z815 816 817class ActNorm(nn.Module):818 def __init__(self, channels, ddi=False, **kwargs):819 super().__init__()820 self.channels = channels821 self.initialized = not ddi822 823 self.logs = nn.Parameter(torch.zeros(1, channels, 1))824 self.bias = nn.Parameter(torch.zeros(1, channels, 1))825 826 def forward(self, x, x_mask=None, g=None, reverse=False, **kwargs):827 if x_mask is None:828 x_mask = torch.ones(x.size(0), 1, x.size(2)).to(829 device=x.device, dtype=x.dtype830 )831 x_len = torch.sum(x_mask, [1, 2])832 if not self.initialized:833 self.initialize(x, x_mask)834 self.initialized = True835 836 if reverse:837 z = (x - self.bias) * torch.exp(-self.logs) * x_mask838 logdet = None839 return z840 else:841 z = (self.bias + torch.exp(self.logs) * x) * x_mask842 logdet = torch.sum(self.logs) * x_len # [b]843 return z, logdet844 845 def store_inverse(self):846 pass847 848 def set_ddi(self, ddi):849 self.initialized = not ddi850 851 def initialize(self, x, x_mask):852 with torch.no_grad():853 denom = torch.sum(x_mask, [0, 2])854 m = torch.sum(x * x_mask, [0, 2]) / denom855 m_sq = torch.sum(x * x * x_mask, [0, 2]) / denom856 v = m_sq - (m**2)857 logs = 0.5 * torch.log(torch.clamp_min(v, 1e-6))858 859 bias_init = (860 (-m * torch.exp(-logs)).view(*self.bias.shape).to(dtype=self.bias.dtype)861 )862 logs_init = (-logs).view(*self.logs.shape).to(dtype=self.logs.dtype)863 864 self.bias.data.copy_(bias_init)865 self.logs.data.copy_(logs_init)866 867 868class InvConvNear(nn.Module):869 def __init__(self, channels, n_split=4, no_jacobian=False, **kwargs):870 super().__init__()871 assert n_split % 2 == 0872 self.channels = channels873 self.n_split = n_split874 self.no_jacobian = no_jacobian875 876 w_init = torch.linalg.qr(877 torch.FloatTensor(self.n_split, self.n_split).normal_()878 )[0]879 if torch.det(w_init) < 0:880 w_init[:, 0] = -1 * w_init[:, 0]881 self.weight = nn.Parameter(w_init)882 883 def forward(self, x, x_mask=None, g=None, reverse=False, **kwargs):884 b, c, t = x.size()885 assert c % self.n_split == 0886 if x_mask is None:887 x_mask = 1888 x_len = torch.ones((b,), dtype=x.dtype, device=x.device) * t889 else:890 x_len = torch.sum(x_mask, [1, 2])891 892 x = x.view(b, 2, c // self.n_split, self.n_split // 2, t)893 x = (894 x.permute(0, 1, 3, 2, 4)895 .contiguous()896 .view(b, self.n_split, c // self.n_split, t)897 )898 899 if reverse:900 if hasattr(self, "weight_inv"):901 weight = self.weight_inv902 else:903 weight = torch.inverse(self.weight.float()).to(dtype=self.weight.dtype)904 logdet = None905 else:906 weight = self.weight907 if self.no_jacobian:908 logdet = 0909 else:910 logdet = torch.logdet(self.weight) * (c / self.n_split) * x_len # [b]911 912 weight = weight.view(self.n_split, self.n_split, 1, 1)913 z = F.conv2d(x, weight)914 915 z = z.view(b, 2, self.n_split // 2, c // self.n_split, t)916 z = z.permute(0, 1, 3, 2, 4).contiguous().view(b, c, t) * x_mask917 if reverse:918 return z919 else:920 return z, logdet921 922 def store_inverse(self):923 self.weight_inv = torch.inverse(self.weight.float()).to(dtype=self.weight.dtype)924 