| | |
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| | | |
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| | | class DefaultFrontend(AbsFrontend): |
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| | | """Conventional frontend structure for ASR. |
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| | | |
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| | | Stft -> WPE -> MVDR-Beamformer -> Power-spec -> Mel-Fbank -> CMVN |
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| | | """ |
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| | | |
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| | |
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| | | if input_stft.dim() == 4: |
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| | | # h: (B, T, C, F) -> h: (B, T, F) |
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| | | if self.training: |
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| | | if self.use_channel == None: |
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| | | input_stft = input_stft[:, :, 0, :] |
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| | | if self.use_channel is not None: |
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| | | input_stft = input_stft[:, :, self.use_channel, :] |
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| | | else: |
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| | | # Select 1ch randomly |
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| | | ch = np.random.randint(input_stft.size(2)) |
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| | |
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| | | |
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| | | class MultiChannelFrontend(AbsFrontend): |
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| | | """Conventional frontend structure for ASR. |
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| | | |
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| | | Stft -> WPE -> MVDR-Beamformer -> Power-spec -> Mel-Fbank -> CMVN |
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| | | """ |
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| | | |
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