| | |
| | | from typing import Tuple |
| | | from typing import Union |
| | | from funasr.modules.nets_utils import make_non_pad_mask |
| | | from torch.nn import functional as F |
| | | import math |
| | | |
| | | VAR2STD_EPSILON = 1e-12 |
| | | |
| | | class StatisticPooling(torch.nn.Module): |
| | | def __init__(self, pooling_dim: Union[int, Tuple] = 2, eps=1e-12): |
| | |
| | | stat_pooling = torch.cat([mean, stddev], dim=1) |
| | | |
| | | return stat_pooling |
| | | |
| | | def convert_tf2torch(self, var_dict_tf, var_dict_torch): |
| | | return {} |
| | | |
| | | |
| | | def statistic_pooling( |
| | | xs_pad: torch.Tensor, |
| | | ilens: torch.Tensor = None, |
| | | pooling_dim: Tuple = (2, 3) |
| | | ) -> torch.Tensor: |
| | | # xs_pad in (Batch, Channel, Time, Frequency) |
| | | |
| | | if ilens is None: |
| | | seq_mask = torch.ones_like(xs_pad).to(xs_pad) |
| | | else: |
| | | seq_mask = make_non_pad_mask(ilens, xs_pad, length_dim=2).to(xs_pad) |
| | | mean = (torch.sum(xs_pad, dim=pooling_dim, keepdim=True) / |
| | | torch.sum(seq_mask, dim=pooling_dim, keepdim=True)) |
| | | squared_difference = torch.pow(xs_pad - mean, 2.0) |
| | | variance = (torch.sum(squared_difference, dim=pooling_dim, keepdim=True) / |
| | | torch.sum(seq_mask, dim=pooling_dim, keepdim=True)) |
| | | for i in reversed(pooling_dim): |
| | | mean, variance = torch.squeeze(mean, dim=i), torch.squeeze(variance, dim=i) |
| | | |
| | | value_mask = torch.less_equal(variance, VAR2STD_EPSILON).float() |
| | | variance = (1.0 - value_mask) * variance + value_mask * VAR2STD_EPSILON |
| | | stddev = torch.sqrt(variance) |
| | | |
| | | stat_pooling = torch.cat([mean, stddev], dim=1) |
| | | |
| | | return stat_pooling |
| | | |
| | | |
| | | def windowed_statistic_pooling( |
| | | xs_pad: torch.Tensor, |
| | | ilens: torch.Tensor = None, |
| | | pooling_dim: Tuple = (2, 3), |
| | | pooling_size: int = 20, |
| | | pooling_stride: int = 1 |
| | | ) -> Tuple[torch.Tensor, int]: |
| | | # xs_pad in (Batch, Channel, Time, Frequency) |
| | | |
| | | tt = xs_pad.shape[2] |
| | | num_chunk = int(math.ceil(tt / pooling_stride)) |
| | | pad = pooling_size // 2 |
| | | features = F.pad(xs_pad, (0, 0, pad, pad), "reflect") |
| | | stat_list = [] |
| | | |
| | | for i in range(num_chunk): |
| | | # B x C |
| | | st, ed = i*pooling_stride, i*pooling_stride+pooling_size |
| | | stat = statistic_pooling(features[:, :, st: ed, :], pooling_dim=pooling_dim) |
| | | stat_list.append(stat.unsqueeze(2)) |
| | | |
| | | # B x C x T |
| | | return torch.cat(stat_list, dim=2), ilens / pooling_stride |