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fbfc98f1d3
* Add streaming Emformer stateless RNN-T. * Update results for streaming Emformer. * Minor fixes.
53 lines
1.8 KiB
Python
53 lines
1.8 KiB
Python
# Copyright 2021 Xiaomi Corp. (authors: Fangjun Kuang)
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#
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# See ../../../../LICENSE for clarification regarding multiple authors
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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import torch
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import torch.nn as nn
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import torch.nn.functional as F
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class Joiner(nn.Module):
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def __init__(self, input_dim: int, inner_dim: int, output_dim: int):
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super().__init__()
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self.inner_linear = nn.Linear(input_dim, inner_dim)
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self.output_linear = nn.Linear(inner_dim, output_dim)
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def forward(
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self, encoder_out: torch.Tensor, decoder_out: torch.Tensor
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) -> torch.Tensor:
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"""
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Args:
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encoder_out:
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Output from the encoder. Its shape is (N, T, s_range, C) during
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training or (N, C) in case of streaming decoding.
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decoder_out:
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Output from the decoder. Its shape is (N, T, s_range, C) during
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training or (N, C) in case of streaming decoding.
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Return a tensor of shape (N, T, s_range, C).
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"""
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assert encoder_out.ndim == decoder_out.ndim
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assert encoder_out.ndim in (2, 4)
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assert encoder_out.shape == decoder_out.shape
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logit = encoder_out + decoder_out
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logit = self.inner_linear(torch.tanh(logit))
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output = self.output_linear(F.relu(logit))
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return output
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