# Copyright (c) 2022 NVIDIA CORPORATION. # Licensed under the MIT license. # Adapted from https://github.com/jik876/hifi-gan under the MIT license. # LICENSE is in incl_licenses directory. import torch import torch.nn as nn from torch.nn import Conv1d, ConvTranspose1d from torch.nn.utils.parametrizations import weight_norm from torch.nn.utils.parametrize import remove_parametrizations from mmaudio.ext.bigvgan import activations from mmaudio.ext.bigvgan.alias_free_torch import * from mmaudio.ext.bigvgan.utils import get_padding, init_weights LRELU_SLOPE = 0.1 class AMPBlock1(torch.nn.Module): def __init__(self, h, channels, kernel_size=3, dilation=(1, 3, 5), activation=None): super(AMPBlock1, self).__init__() self.h = h self.convs1 = nn.ModuleList([ weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=dilation[0], padding=get_padding(kernel_size, dilation[0]))), weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=dilation[1], padding=get_padding(kernel_size, dilation[1]))), weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=dilation[2], padding=get_padding(kernel_size, dilation[2]))) ]) self.convs1.apply(init_weights) self.convs2 = nn.ModuleList([ weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=1, padding=get_padding(kernel_size, 1))), weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=1, padding=get_padding(kernel_size, 1))), weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=1, padding=get_padding(kernel_size, 1))) ]) self.convs2.apply(init_weights) self.num_layers = len(self.convs1) + len(self.convs2) # total number of conv layers if activation == 'snake': # periodic nonlinearity with snake function and anti-aliasing self.activations = nn.ModuleList([ Activation1d( activation=activations.Snake(channels, alpha_logscale=h.snake_logscale)) for _ in range(self.num_layers) ]) elif activation == 'snakebeta': # periodic nonlinearity with snakebeta function and anti-aliasing self.activations = nn.ModuleList([ Activation1d( activation=activations.SnakeBeta(channels, alpha_logscale=h.snake_logscale)) for _ in range(self.num_layers) ]) else: raise NotImplementedError( "activation incorrectly specified. check the config file and look for 'activation'." ) def forward(self, x): acts1, acts2 = self.activations[::2], self.activations[1::2] for c1, c2, a1, a2 in zip(self.convs1, self.convs2, acts1, acts2): xt = a1(x) xt = c1(xt) xt = a2(xt) xt = c2(xt) x = xt + x return x def remove_weight_norm(self): for l in self.convs1: remove_parametrizations(l, 'weight') for l in self.convs2: remove_parametrizations(l, 'weight') class AMPBlock2(torch.nn.Module): def __init__(self, h, channels, kernel_size=3, dilation=(1, 3), activation=None): super(AMPBlock2, self).__init__() self.h = h self.convs = nn.ModuleList([ weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=dilation[0], padding=get_padding(kernel_size, dilation[0]))), weight_norm( Conv1d(channels, channels, kernel_size, 1, dilation=dilation[1], padding=get_padding(kernel_size, dilation[1]))) ]) self.convs.apply(init_weights) self.num_layers = len(self.convs) # total number of conv layers if activation == 'snake': # periodic nonlinearity with snake function and anti-aliasing self.activations = nn.ModuleList([ Activation1d( activation=activations.Snake(channels, alpha_logscale=h.snake_logscale)) for _ in range(self.num_layers) ]) elif activation == 'snakebeta': # periodic nonlinearity with snakebeta function and anti-aliasing self.activations = nn.ModuleList([ Activation1d( activation=activations.SnakeBeta(channels, alpha_logscale=h.snake_logscale)) for _ in range(self.num_layers) ]) else: raise NotImplementedError( "activation incorrectly specified. check the config file and look for 'activation'." ) def forward(self, x): for c, a in zip(self.convs, self.activations): xt = a(x) xt = c(xt) x = xt + x return x def remove_weight_norm(self): for l in self.convs: remove_parametrizations(l, 'weight') class BigVGANVocoder(torch.nn.Module): # this is our main BigVGAN model. Applies anti-aliased periodic activation for resblocks. def __init__(self, h): super().__init__() self.h = h self.num_kernels = len(h.resblock_kernel_sizes) self.num_upsamples = len(h.upsample_rates) # pre conv self.conv_pre = weight_norm(Conv1d(h.num_mels, h.upsample_initial_channel, 7, 1, padding=3)) # define which AMPBlock to use. BigVGAN uses AMPBlock1 as default resblock = AMPBlock1 if h.resblock == '1' else AMPBlock2 # transposed conv-based upsamplers. does not apply anti-aliasing self.ups = nn.ModuleList() for i, (u, k) in enumerate(zip(h.upsample_rates, h.upsample_kernel_sizes)): self.ups.append( nn.ModuleList([ weight_norm( ConvTranspose1d(h.upsample_initial_channel // (2**i), h.upsample_initial_channel // (2**(i + 1)), k, u, padding=(k - u) // 2)) ])) # residual blocks using anti-aliased multi-periodicity composition modules (AMP) self.resblocks = nn.ModuleList() for i in range(len(self.ups)): ch = h.upsample_initial_channel // (2**(i + 1)) for j, (k, d) in enumerate(zip(h.resblock_kernel_sizes, h.resblock_dilation_sizes)): self.resblocks.append(resblock(h, ch, k, d, activation=h.activation)) # post conv if h.activation == "snake": # periodic nonlinearity with snake function and anti-aliasing activation_post = activations.Snake(ch, alpha_logscale=h.snake_logscale) self.activation_post = Activation1d(activation=activation_post) elif h.activation == "snakebeta": # periodic nonlinearity with snakebeta function and anti-aliasing activation_post = activations.SnakeBeta(ch, alpha_logscale=h.snake_logscale) self.activation_post = Activation1d(activation=activation_post) else: raise NotImplementedError( "activation incorrectly specified. check the config file and look for 'activation'." ) self.conv_post = weight_norm(Conv1d(ch, 1, 7, 1, padding=3)) # weight initialization for i in range(len(self.ups)): self.ups[i].apply(init_weights) self.conv_post.apply(init_weights) def forward(self, x): # pre conv x = self.conv_pre(x) for i in range(self.num_upsamples): # upsampling for i_up in range(len(self.ups[i])): x = self.ups[i][i_up](x) # AMP blocks xs = None for j in range(self.num_kernels): if xs is None: xs = self.resblocks[i * self.num_kernels + j](x) else: xs += self.resblocks[i * self.num_kernels + j](x) x = xs / self.num_kernels # post conv x = self.activation_post(x) x = self.conv_post(x) x = torch.tanh(x) return x def remove_weight_norm(self): print('Removing weight norm...') for l in self.ups: for l_i in l: remove_parametrizations(l_i, 'weight') for l in self.resblocks: l.remove_weight_norm() remove_parametrizations(self.conv_pre, 'weight') remove_parametrizations(self.conv_post, 'weight')