import math import torch from torch.nn import functional as F def init_weights(m, mean=0.0, std=0.01): classname = m.__class__.__name__ if classname.find("Conv") != -1: m.weight.data.normal_(mean, std) def get_padding(kernel_size, dilation=1): return int((kernel_size * dilation - dilation) / 2) def convert_pad_shape(pad_shape): layer = pad_shape[::-1] pad_shape = [item for sublist in layer for item in sublist] return pad_shape def intersperse(lst, item): result = [item] * (len(lst) * 2 + 1) result[1::2] = lst return result def kl_divergence(m_p, logs_p, m_q, logs_q): """KL(P||Q)""" kl = (logs_q - logs_p) - 0.5 kl += ( 0.5 * (torch.exp(2.0 * logs_p) + ((m_p - m_q) ** 2)) * torch.exp(-2.0 * logs_q) ) return kl def rand_gumbel(shape): """Sample from the Gumbel distribution, protect from overflows.""" uniform_samples = torch.rand(shape) * 0.99998 + 0.00001 return -torch.log(-torch.log(uniform_samples)) def rand_gumbel_like(x): g = rand_gumbel(x.size()).to(dtype=x.dtype, device=x.device) return g def slice_segments(x, ids_str, segment_size=4): ret = torch.zeros_like(x[:, :, :segment_size]) for i in range(x.size(0)): idx_str = ids_str[i] idx_end = idx_str + segment_size ret[i] = x[i, :, idx_str:idx_end] return ret def rand_slice_segments(x, x_lengths=None, segment_size=4): b, d, t = x.size() if x_lengths is None: x_lengths = t ids_str_max = x_lengths - segment_size + 1 ids_str = (torch.rand([b]).to(device=x.device) * ids_str_max).to(dtype=torch.long) ret = slice_segments(x, ids_str, segment_size) return ret, ids_str def get_timing_signal_1d(length, channels, min_timescale=1.0, max_timescale=1.0e4): position = torch.arange(length, dtype=torch.float) num_timescales = channels // 2 log_timescale_increment = math.log(float(max_timescale) / float(min_timescale)) / ( num_timescales - 1 ) inv_timescales = min_timescale * torch.exp( torch.arange(num_timescales, dtype=torch.float) * -log_timescale_increment ) scaled_time = position.unsqueeze(0) * inv_timescales.unsqueeze(1) signal = torch.cat([torch.sin(scaled_time), torch.cos(scaled_time)], 0) signal = F.pad(signal, [0, 0, 0, channels % 2]) signal = signal.view(1, channels, length) return signal def add_timing_signal_1d(x, min_timescale=1.0, max_timescale=1.0e4): b, channels, length = x.size() signal = get_timing_signal_1d(length, channels, min_timescale, max_timescale) return x + signal.to(dtype=x.dtype, device=x.device) def cat_timing_signal_1d(x, min_timescale=1.0, max_timescale=1.0e4, axis=1): b, channels, length = x.size() signal = get_timing_signal_1d(length, channels, min_timescale, max_timescale) return torch.cat([x, signal.to(dtype=x.dtype, device=x.device)], axis) def subsequent_mask(length): mask = torch.tril(torch.ones(length, length)).unsqueeze(0).unsqueeze(0) return mask @torch.jit.script def fused_add_tanh_sigmoid_multiply(input_a, input_b, n_channels): n_channels_int = n_channels[0] in_act = input_a + input_b t_act = torch.tanh(in_act[:, :n_channels_int, :]) s_act = torch.sigmoid(in_act[:, n_channels_int:, :]) acts = t_act * s_act return acts def convert_pad_shape(pad_shape): layer = pad_shape[::-1] pad_shape = [item for sublist in layer for item in sublist] return pad_shape def shift_1d(x): x = F.pad(x, convert_pad_shape([[0, 0], [0, 0], [1, 0]]))[:, :, :-1] return x def sequence_mask(length, max_length=None): if max_length is None: max_length = length.max() x = torch.arange(max_length, dtype=length.dtype, device=length.device) return x.unsqueeze(0) < length.unsqueeze(1) def generate_path(duration, mask): """ duration: [b, 1, t_x] mask: [b, 1, t_y, t_x] """ b, _, t_y, t_x = mask.shape cum_duration = torch.cumsum(duration, -1) cum_duration_flat = cum_duration.view(b * t_x) path = sequence_mask(cum_duration_flat, t_y).to(mask.dtype) path = path.view(b, t_x, t_y) path = path - F.pad(path, convert_pad_shape([[0, 0], [1, 0], [0, 0]]))[:, :-1] path = path.unsqueeze(1).transpose(2, 3) * mask return path def clip_grad_value_(parameters, clip_value, norm_type=2): if isinstance(parameters, torch.Tensor): parameters = [parameters] parameters = list(filter(lambda p: p.grad is not None, parameters)) norm_type = float(norm_type) if clip_value is not None: clip_value = float(clip_value) total_norm = 0 for p in parameters: if clip_value is not None: p.grad.data.clamp_(min=-clip_value, max=clip_value) param_norm = p.grad.data.norm(norm_type) total_norm += param_norm.item() ** norm_type total_norm = total_norm ** (1.0 / norm_type) return total_norm