decoders.py

# This script is modified from https://github.com/EricGuo5513/TM2T
# Licensed under: https://github.com/EricGuo5513/TM2T/blob/main/LICENSE

import torch.nn as nn


class VQDecoderV3(nn.Module):
    def __init__(self, args):
        super(VQDecoderV3, self).__init__()
        n_up = args.vae_layer
        channels = []
        for i in range(n_up - 1):
            channels.append(args.vae_length)
        channels.append(args.vae_length)
        channels.append(args.vae_test_dim)
        input_size = args.vae_length
        n_resblk = 2
        assert len(channels) == n_up + 1
        if input_size == channels[0]:
            layers = []
        else:
            layers = [nn.Conv1d(input_size, channels[0], kernel_size=3, stride=1, padding=1)]

        for i in range(n_resblk):
            layers += [ResBlock(channels[0])]
        # channels = channels
        for i in range(n_up):
            layers += [
                nn.Upsample(scale_factor=2, mode="nearest"),
                nn.Conv1d(channels[i], channels[i + 1], kernel_size=3, stride=1, padding=1),
                nn.LeakyReLU(0.2, inplace=True),
            ]
        layers += [nn.Conv1d(channels[-1], channels[-1], kernel_size=3, stride=1, padding=1)]
        self.main = nn.Sequential(*layers)
        # self.main.apply(init_weight)

    def forward(self, inputs):
        inputs = inputs.permute(0, 2, 1)
        outputs = self.main(inputs).permute(0, 2, 1)
        return outputs


class ResBlock(nn.Module):
    def __init__(self, channel):
        super(ResBlock, self).__init__()
        self.model = nn.Sequential(
            nn.Conv1d(channel, channel, kernel_size=3, stride=1, padding=1),
            nn.LeakyReLU(0.2, inplace=True),
            nn.Conv1d(channel, channel, kernel_size=3, stride=1, padding=1),
        )

    def forward(self, x):
        residual = x
        out = self.model(x)
        out += residual
        return out