1020 lines
36 KiB
Python
1020 lines
36 KiB
Python
# Copyright (c) Facebook, Inc. and its affiliates.
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#
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# This source code is licensed under the MIT license found in the
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# LICENSE file in the root directory of this source tree.
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import argparse
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import math
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from collections.abc import Iterable
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import torch
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import torch.nn as nn
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from examples.speech_recognition.data.data_utils import lengths_to_encoder_padding_mask
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from fairseq import utils
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from fairseq.models import (
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FairseqEncoder,
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FairseqEncoderDecoderModel,
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FairseqEncoderModel,
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FairseqIncrementalDecoder,
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register_model,
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register_model_architecture,
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)
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from fairseq.modules import (
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LinearizedConvolution,
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TransformerDecoderLayer,
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TransformerEncoderLayer,
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VGGBlock,
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)
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@register_model("asr_vggtransformer")
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class VGGTransformerModel(FairseqEncoderDecoderModel):
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"""
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Transformers with convolutional context for ASR
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https://arxiv.org/abs/1904.11660
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"""
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def __init__(self, encoder, decoder):
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super().__init__(encoder, decoder)
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@staticmethod
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def add_args(parser):
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"""Add model-specific arguments to the parser."""
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parser.add_argument(
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"--input-feat-per-channel",
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type=int,
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metavar="N",
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help="encoder input dimension per input channel",
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)
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parser.add_argument(
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"--vggblock-enc-config",
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type=str,
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metavar="EXPR",
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help="""
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an array of tuples each containing the configuration of one vggblock:
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[(out_channels,
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conv_kernel_size,
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pooling_kernel_size,
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num_conv_layers,
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use_layer_norm), ...])
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""",
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)
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parser.add_argument(
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"--transformer-enc-config",
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type=str,
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metavar="EXPR",
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help=""""
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a tuple containing the configuration of the encoder transformer layers
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configurations:
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[(input_dim,
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num_heads,
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ffn_dim,
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normalize_before,
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dropout,
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attention_dropout,
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relu_dropout), ...]')
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""",
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)
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parser.add_argument(
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"--enc-output-dim",
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type=int,
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metavar="N",
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help="""
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encoder output dimension, can be None. If specified, projecting the
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transformer output to the specified dimension""",
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)
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parser.add_argument(
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"--in-channels",
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type=int,
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metavar="N",
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help="number of encoder input channels",
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)
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parser.add_argument(
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"--tgt-embed-dim",
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type=int,
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metavar="N",
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help="embedding dimension of the decoder target tokens",
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)
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parser.add_argument(
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"--transformer-dec-config",
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type=str,
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metavar="EXPR",
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help="""
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a tuple containing the configuration of the decoder transformer layers
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configurations:
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[(input_dim,
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num_heads,
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ffn_dim,
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normalize_before,
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dropout,
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attention_dropout,
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relu_dropout), ...]
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""",
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)
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parser.add_argument(
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"--conv-dec-config",
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type=str,
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metavar="EXPR",
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help="""
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an array of tuples for the decoder 1-D convolution config
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[(out_channels, conv_kernel_size, use_layer_norm), ...]""",
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)
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@classmethod
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def build_encoder(cls, args, task):
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return VGGTransformerEncoder(
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input_feat_per_channel=args.input_feat_per_channel,
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vggblock_config=eval(args.vggblock_enc_config),
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transformer_config=eval(args.transformer_enc_config),
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encoder_output_dim=args.enc_output_dim,
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in_channels=args.in_channels,
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)
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@classmethod
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def build_decoder(cls, args, task):
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return TransformerDecoder(
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dictionary=task.target_dictionary,
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embed_dim=args.tgt_embed_dim,
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transformer_config=eval(args.transformer_dec_config),
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conv_config=eval(args.conv_dec_config),
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encoder_output_dim=args.enc_output_dim,
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)
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@classmethod
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def build_model(cls, args, task):
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"""Build a new model instance."""
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# make sure that all args are properly defaulted
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# (in case there are any new ones)
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base_architecture(args)
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encoder = cls.build_encoder(args, task)
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decoder = cls.build_decoder(args, task)
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return cls(encoder, decoder)
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def get_normalized_probs(self, net_output, log_probs, sample=None):
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# net_output['encoder_out'] is a (B, T, D) tensor
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lprobs = super().get_normalized_probs(net_output, log_probs, sample)
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lprobs.batch_first = True
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return lprobs
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DEFAULT_ENC_VGGBLOCK_CONFIG = ((32, 3, 2, 2, False),) * 2
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DEFAULT_ENC_TRANSFORMER_CONFIG = ((256, 4, 1024, True, 0.2, 0.2, 0.2),) * 2
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# 256: embedding dimension
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# 4: number of heads
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# 1024: FFN
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# True: apply layerNorm before (dropout + resiaul) instead of after
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# 0.2 (dropout): dropout after MultiheadAttention and second FC
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# 0.2 (attention_dropout): dropout in MultiheadAttention
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# 0.2 (relu_dropout): dropout after ReLu
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DEFAULT_DEC_TRANSFORMER_CONFIG = ((256, 2, 1024, True, 0.2, 0.2, 0.2),) * 2
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DEFAULT_DEC_CONV_CONFIG = ((256, 3, True),) * 2
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# TODO: repace transformer encoder config from one liner
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# to explicit args to get rid of this transformation
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def prepare_transformer_encoder_params(
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input_dim,
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num_heads,
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ffn_dim,
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normalize_before,
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dropout,
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attention_dropout,
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relu_dropout,
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):
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args = argparse.Namespace()
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args.encoder_embed_dim = input_dim
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args.encoder_attention_heads = num_heads
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args.attention_dropout = attention_dropout
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args.dropout = dropout
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args.activation_dropout = relu_dropout
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args.encoder_normalize_before = normalize_before
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args.encoder_ffn_embed_dim = ffn_dim
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return args
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def prepare_transformer_decoder_params(
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input_dim,
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num_heads,
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ffn_dim,
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normalize_before,
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dropout,
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attention_dropout,
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relu_dropout,
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):
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args = argparse.Namespace()
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args.decoder_embed_dim = input_dim
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args.decoder_attention_heads = num_heads
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args.attention_dropout = attention_dropout
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args.dropout = dropout
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args.activation_dropout = relu_dropout
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args.decoder_normalize_before = normalize_before
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args.decoder_ffn_embed_dim = ffn_dim
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return args
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class VGGTransformerEncoder(FairseqEncoder):
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"""VGG + Transformer encoder"""
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def __init__(
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self,
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input_feat_per_channel,
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vggblock_config=DEFAULT_ENC_VGGBLOCK_CONFIG,
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transformer_config=DEFAULT_ENC_TRANSFORMER_CONFIG,
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encoder_output_dim=512,
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in_channels=1,
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transformer_context=None,
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transformer_sampling=None,
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):
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"""constructor for VGGTransformerEncoder
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Args:
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- input_feat_per_channel: feature dim (not including stacked,
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just base feature)
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- in_channel: # input channels (e.g., if stack 8 feature vector
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together, this is 8)
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- vggblock_config: configuration of vggblock, see comments on
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DEFAULT_ENC_VGGBLOCK_CONFIG
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- transformer_config: configuration of transformer layer, see comments
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on DEFAULT_ENC_TRANSFORMER_CONFIG
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- encoder_output_dim: final transformer output embedding dimension
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- transformer_context: (left, right) if set, self-attention will be focused
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on (t-left, t+right)
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- transformer_sampling: an iterable of int, must match with
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len(transformer_config), transformer_sampling[i] indicates sampling
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factor for i-th transformer layer, after multihead att and feedfoward
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part
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"""
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super().__init__(None)
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self.num_vggblocks = 0
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if vggblock_config is not None:
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if not isinstance(vggblock_config, Iterable):
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raise ValueError("vggblock_config is not iterable")
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self.num_vggblocks = len(vggblock_config)
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self.conv_layers = nn.ModuleList()
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self.in_channels = in_channels
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self.input_dim = input_feat_per_channel
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self.pooling_kernel_sizes = []
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if vggblock_config is not None:
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for _, config in enumerate(vggblock_config):
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(
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out_channels,
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conv_kernel_size,
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pooling_kernel_size,
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num_conv_layers,
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layer_norm,
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) = config
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self.conv_layers.append(
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VGGBlock(
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in_channels,
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out_channels,
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conv_kernel_size,
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pooling_kernel_size,
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num_conv_layers,
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input_dim=input_feat_per_channel,
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layer_norm=layer_norm,
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)
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)
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self.pooling_kernel_sizes.append(pooling_kernel_size)
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in_channels = out_channels
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input_feat_per_channel = self.conv_layers[-1].output_dim
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transformer_input_dim = self.infer_conv_output_dim(
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self.in_channels, self.input_dim
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)
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# transformer_input_dim is the output dimension of VGG part
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self.validate_transformer_config(transformer_config)
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self.transformer_context = self.parse_transformer_context(transformer_context)
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self.transformer_sampling = self.parse_transformer_sampling(
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transformer_sampling, len(transformer_config)
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)
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self.transformer_layers = nn.ModuleList()
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if transformer_input_dim != transformer_config[0][0]:
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self.transformer_layers.append(
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Linear(transformer_input_dim, transformer_config[0][0])
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)
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self.transformer_layers.append(
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TransformerEncoderLayer(
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prepare_transformer_encoder_params(*transformer_config[0])
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)
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)
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for i in range(1, len(transformer_config)):
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if transformer_config[i - 1][0] != transformer_config[i][0]:
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self.transformer_layers.append(
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Linear(transformer_config[i - 1][0], transformer_config[i][0])
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)
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self.transformer_layers.append(
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TransformerEncoderLayer(
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prepare_transformer_encoder_params(*transformer_config[i])
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)
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)
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self.encoder_output_dim = encoder_output_dim
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self.transformer_layers.extend(
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[
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Linear(transformer_config[-1][0], encoder_output_dim),
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LayerNorm(encoder_output_dim),
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]
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)
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def forward(self, src_tokens, src_lengths, **kwargs):
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"""
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src_tokens: padded tensor (B, T, C * feat)
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src_lengths: tensor of original lengths of input utterances (B,)
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"""
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bsz, max_seq_len, _ = src_tokens.size()
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x = src_tokens.view(bsz, max_seq_len, self.in_channels, self.input_dim)
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x = x.transpose(1, 2).contiguous()
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# (B, C, T, feat)
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for layer_idx in range(len(self.conv_layers)):
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x = self.conv_layers[layer_idx](x)
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bsz, _, output_seq_len, _ = x.size()
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# (B, C, T, feat) -> (B, T, C, feat) -> (T, B, C, feat) -> (T, B, C * feat)
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x = x.transpose(1, 2).transpose(0, 1)
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x = x.contiguous().view(output_seq_len, bsz, -1)
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input_lengths = src_lengths.clone()
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for s in self.pooling_kernel_sizes:
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input_lengths = (input_lengths.float() / s).ceil().long()
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encoder_padding_mask, _ = lengths_to_encoder_padding_mask(
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input_lengths, batch_first=True
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)
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if not encoder_padding_mask.any():
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encoder_padding_mask = None
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subsampling_factor = int(max_seq_len * 1.0 / output_seq_len + 0.5)
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attn_mask = self.lengths_to_attn_mask(input_lengths, subsampling_factor)
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transformer_layer_idx = 0
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for layer_idx in range(len(self.transformer_layers)):
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if isinstance(self.transformer_layers[layer_idx], TransformerEncoderLayer):
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x = self.transformer_layers[layer_idx](
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x, encoder_padding_mask, attn_mask
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)
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if self.transformer_sampling[transformer_layer_idx] != 1:
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sampling_factor = self.transformer_sampling[transformer_layer_idx]
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x, encoder_padding_mask, attn_mask = self.slice(
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x, encoder_padding_mask, attn_mask, sampling_factor
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)
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transformer_layer_idx += 1
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else:
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x = self.transformer_layers[layer_idx](x)
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# encoder_padding_maks is a (T x B) tensor, its [t, b] elements indicate
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# whether encoder_output[t, b] is valid or not (valid=0, invalid=1)
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return {
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"encoder_out": x, # (T, B, C)
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"encoder_padding_mask": encoder_padding_mask.t()
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if encoder_padding_mask is not None
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else None,
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# (B, T) --> (T, B)
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}
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def infer_conv_output_dim(self, in_channels, input_dim):
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sample_seq_len = 200
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sample_bsz = 10
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x = torch.randn(sample_bsz, in_channels, sample_seq_len, input_dim)
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for i, _ in enumerate(self.conv_layers):
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x = self.conv_layers[i](x)
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x = x.transpose(1, 2)
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mb, seq = x.size()[:2]
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return x.contiguous().view(mb, seq, -1).size(-1)
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def validate_transformer_config(self, transformer_config):
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for config in transformer_config:
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input_dim, num_heads = config[:2]
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if input_dim % num_heads != 0:
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msg = (
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"ERROR in transformer config {}: ".format(config)
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+ "input dimension {} ".format(input_dim)
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+ "not dividable by number of heads {}".format(num_heads)
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)
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raise ValueError(msg)
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def parse_transformer_context(self, transformer_context):
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"""
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transformer_context can be the following:
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- None; indicates no context is used, i.e.,
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transformer can access full context
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- a tuple/list of two int; indicates left and right context,
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any number <0 indicates infinite context
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* e.g., (5, 6) indicates that for query at x_t, transformer can
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access [t-5, t+6] (inclusive)
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* e.g., (-1, 6) indicates that for query at x_t, transformer can
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access [0, t+6] (inclusive)
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"""
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if transformer_context is None:
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return None
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if not isinstance(transformer_context, Iterable):
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raise ValueError("transformer context must be Iterable if it is not None")
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if len(transformer_context) != 2:
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raise ValueError("transformer context must have length 2")
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left_context = transformer_context[0]
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if left_context < 0:
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left_context = None
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right_context = transformer_context[1]
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if right_context < 0:
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right_context = None
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if left_context is None and right_context is None:
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return None
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return (left_context, right_context)
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def parse_transformer_sampling(self, transformer_sampling, num_layers):
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"""
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parsing transformer sampling configuration
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Args:
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- transformer_sampling, accepted input:
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* None, indicating no sampling
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* an Iterable with int (>0) as element
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- num_layers, expected number of transformer layers, must match with
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the length of transformer_sampling if it is not None
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Returns:
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- A tuple with length num_layers
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"""
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if transformer_sampling is None:
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return (1,) * num_layers
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if not isinstance(transformer_sampling, Iterable):
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raise ValueError(
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"transformer_sampling must be an iterable if it is not None"
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)
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if len(transformer_sampling) != num_layers:
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raise ValueError(
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"transformer_sampling {} does not match with the number "
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"of layers {}".format(transformer_sampling, num_layers)
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)
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for layer, value in enumerate(transformer_sampling):
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if not isinstance(value, int):
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raise ValueError("Invalid value in transformer_sampling: ")
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if value < 1:
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raise ValueError(
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"{} layer's subsampling is {}.".format(layer, value)
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+ " This is not allowed! "
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)
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return transformer_sampling
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def slice(self, embedding, padding_mask, attn_mask, sampling_factor):
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"""
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embedding is a (T, B, D) tensor
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padding_mask is a (B, T) tensor or None
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attn_mask is a (T, T) tensor or None
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"""
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embedding = embedding[::sampling_factor, :, :]
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if padding_mask is not None:
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padding_mask = padding_mask[:, ::sampling_factor]
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if attn_mask is not None:
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attn_mask = attn_mask[::sampling_factor, ::sampling_factor]
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return embedding, padding_mask, attn_mask
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def lengths_to_attn_mask(self, input_lengths, subsampling_factor=1):
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"""
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create attention mask according to sequence lengths and transformer
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context
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Args:
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- input_lengths: (B, )-shape Int/Long tensor; input_lengths[b] is
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the length of b-th sequence
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- subsampling_factor: int
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* Note that the left_context and right_context is specified in
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the input frame-level while input to transformer may already
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go through subsampling (e.g., the use of striding in vggblock)
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we use subsampling_factor to scale the left/right context
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Return:
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- a (T, T) binary tensor or None, where T is max(input_lengths)
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* if self.transformer_context is None, None
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* if left_context is None,
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* attn_mask[t, t + right_context + 1:] = 1
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* others = 0
|
|
* if right_context is None,
|
|
* attn_mask[t, 0:t - left_context] = 1
|
|
* others = 0
|
|
* elsif
|
|
* attn_mask[t, t - left_context: t + right_context + 1] = 0
|
|
* others = 1
|
|
"""
|
|
if self.transformer_context is None:
|
|
return None
|
|
|
|
maxT = torch.max(input_lengths).item()
|
|
attn_mask = torch.zeros(maxT, maxT)
|
|
|
|
left_context = self.transformer_context[0]
|
|
right_context = self.transformer_context[1]
|
|
if left_context is not None:
|
|
left_context = math.ceil(self.transformer_context[0] / subsampling_factor)
|
|
if right_context is not None:
|
|
right_context = math.ceil(self.transformer_context[1] / subsampling_factor)
|
|
|
|
for t in range(maxT):
|
|
if left_context is not None:
|
|
st = 0
|
|
en = max(st, t - left_context)
|
|
attn_mask[t, st:en] = 1
|
|
if right_context is not None:
|
|
st = t + right_context + 1
|
|
st = min(st, maxT - 1)
|
|
attn_mask[t, st:] = 1
|
|
|
|
return attn_mask.to(input_lengths.device)
|
|
|
|
def reorder_encoder_out(self, encoder_out, new_order):
|
|
encoder_out["encoder_out"] = encoder_out["encoder_out"].index_select(
|
|
1, new_order
|
|
)
|
|
if encoder_out["encoder_padding_mask"] is not None:
|
|
encoder_out["encoder_padding_mask"] = encoder_out[
|
|
"encoder_padding_mask"
|
|
].index_select(1, new_order)
|
|
return encoder_out
|
|
|
|
|
|
class TransformerDecoder(FairseqIncrementalDecoder):
|
|
"""
|
|
Transformer decoder consisting of *args.decoder_layers* layers. Each layer
|
|
is a :class:`TransformerDecoderLayer`.
|
|
Args:
|
|
args (argparse.Namespace): parsed command-line arguments
|
|
dictionary (~fairseq.data.Dictionary): decoding dictionary
|
|
embed_tokens (torch.nn.Embedding): output embedding
|
|
no_encoder_attn (bool, optional): whether to attend to encoder outputs.
|
|
Default: ``False``
|
|
left_pad (bool, optional): whether the input is left-padded. Default:
|
|
``False``
|
|
"""
|
|
|
|
def __init__(
|
|
self,
|
|
dictionary,
|
|
embed_dim=512,
|
|
transformer_config=DEFAULT_ENC_TRANSFORMER_CONFIG,
|
|
conv_config=DEFAULT_DEC_CONV_CONFIG,
|
|
encoder_output_dim=512,
|
|
):
|
|
|
|
super().__init__(dictionary)
|
|
vocab_size = len(dictionary)
|
|
self.padding_idx = dictionary.pad()
|
|
self.embed_tokens = Embedding(vocab_size, embed_dim, self.padding_idx)
|
|
|
|
self.conv_layers = nn.ModuleList()
|
|
for i in range(len(conv_config)):
|
|
out_channels, kernel_size, layer_norm = conv_config[i]
|
|
if i == 0:
|
|
conv_layer = LinearizedConv1d(
|
|
embed_dim, out_channels, kernel_size, padding=kernel_size - 1
|
|
)
|
|
else:
|
|
conv_layer = LinearizedConv1d(
|
|
conv_config[i - 1][0],
|
|
out_channels,
|
|
kernel_size,
|
|
padding=kernel_size - 1,
|
|
)
|
|
self.conv_layers.append(conv_layer)
|
|
if layer_norm:
|
|
self.conv_layers.append(nn.LayerNorm(out_channels))
|
|
self.conv_layers.append(nn.ReLU())
|
|
|
|
self.layers = nn.ModuleList()
|
|
if conv_config[-1][0] != transformer_config[0][0]:
|
|
self.layers.append(Linear(conv_config[-1][0], transformer_config[0][0]))
|
|
self.layers.append(
|
|
TransformerDecoderLayer(
|
|
prepare_transformer_decoder_params(*transformer_config[0])
|
|
)
|
|
)
|
|
|
|
for i in range(1, len(transformer_config)):
|
|
if transformer_config[i - 1][0] != transformer_config[i][0]:
|
|
self.layers.append(
|
|
Linear(transformer_config[i - 1][0], transformer_config[i][0])
|
|
)
|
|
self.layers.append(
|
|
TransformerDecoderLayer(
|
|
prepare_transformer_decoder_params(*transformer_config[i])
|
|
)
|
|
)
|
|
self.fc_out = Linear(transformer_config[-1][0], vocab_size)
|
|
|
|
def forward(self, prev_output_tokens, encoder_out=None, incremental_state=None):
|
|
"""
|
|
Args:
|
|
prev_output_tokens (LongTensor): previous decoder outputs of shape
|
|
`(batch, tgt_len)`, for input feeding/teacher forcing
|
|
encoder_out (Tensor, optional): output from the encoder, used for
|
|
encoder-side attention
|
|
incremental_state (dict): dictionary used for storing state during
|
|
:ref:`Incremental decoding`
|
|
Returns:
|
|
tuple:
|
|
- the last decoder layer's output of shape `(batch, tgt_len,
|
|
vocab)`
|
|
- the last decoder layer's attention weights of shape `(batch,
|
|
tgt_len, src_len)`
|
|
"""
|
|
target_padding_mask = (
|
|
(prev_output_tokens == self.padding_idx).to(prev_output_tokens.device)
|
|
if incremental_state is None
|
|
else None
|
|
)
|
|
|
|
if incremental_state is not None:
|
|
prev_output_tokens = prev_output_tokens[:, -1:]
|
|
|
|
# embed tokens
|
|
x = self.embed_tokens(prev_output_tokens)
|
|
|
|
# B x T x C -> T x B x C
|
|
x = self._transpose_if_training(x, incremental_state)
|
|
|
|
for layer in self.conv_layers:
|
|
if isinstance(layer, LinearizedConvolution):
|
|
x = layer(x, incremental_state)
|
|
else:
|
|
x = layer(x)
|
|
|
|
# B x T x C -> T x B x C
|
|
x = self._transpose_if_inference(x, incremental_state)
|
|
|
|
# decoder layers
|
|
for layer in self.layers:
|
|
if isinstance(layer, TransformerDecoderLayer):
|
|
x, *_ = layer(
|
|
x,
|
|
(encoder_out["encoder_out"] if encoder_out is not None else None),
|
|
(
|
|
encoder_out["encoder_padding_mask"].t()
|
|
if encoder_out["encoder_padding_mask"] is not None
|
|
else None
|
|
),
|
|
incremental_state,
|
|
self_attn_mask=(
|
|
self.buffered_future_mask(x)
|
|
if incremental_state is None
|
|
else None
|
|
),
|
|
self_attn_padding_mask=(
|
|
target_padding_mask if incremental_state is None else None
|
|
),
|
|
)
|
|
else:
|
|
x = layer(x)
|
|
|
|
# T x B x C -> B x T x C
|
|
x = x.transpose(0, 1)
|
|
|
|
x = self.fc_out(x)
|
|
|
|
return x, None
|
|
|
|
def buffered_future_mask(self, tensor):
|
|
dim = tensor.size(0)
|
|
if (
|
|
not hasattr(self, "_future_mask")
|
|
or self._future_mask is None
|
|
or self._future_mask.device != tensor.device
|
|
):
|
|
self._future_mask = torch.triu(
|
|
utils.fill_with_neg_inf(tensor.new(dim, dim)), 1
|
|
)
|
|
if self._future_mask.size(0) < dim:
|
|
self._future_mask = torch.triu(
|
|
utils.fill_with_neg_inf(self._future_mask.resize_(dim, dim)), 1
|
|
)
|
|
return self._future_mask[:dim, :dim]
|
|
|
|
def _transpose_if_training(self, x, incremental_state):
|
|
if incremental_state is None:
|
|
x = x.transpose(0, 1)
|
|
return x
|
|
|
|
def _transpose_if_inference(self, x, incremental_state):
|
|
if incremental_state:
|
|
x = x.transpose(0, 1)
|
|
return x
|
|
|
|
|
|
@register_model("asr_vggtransformer_encoder")
|
|
class VGGTransformerEncoderModel(FairseqEncoderModel):
|
|
def __init__(self, encoder):
|
|
super().__init__(encoder)
|
|
|
|
@staticmethod
|
|
def add_args(parser):
|
|
"""Add model-specific arguments to the parser."""
|
|
parser.add_argument(
|
|
"--input-feat-per-channel",
|
|
type=int,
|
|
metavar="N",
|
|
help="encoder input dimension per input channel",
|
|
)
|
|
parser.add_argument(
|
|
"--vggblock-enc-config",
|
|
type=str,
|
|
metavar="EXPR",
|
|
help="""
|
|
an array of tuples each containing the configuration of one vggblock
|
|
[(out_channels, conv_kernel_size, pooling_kernel_size,num_conv_layers), ...]
|
|
""",
|
|
)
|
|
parser.add_argument(
|
|
"--transformer-enc-config",
|
|
type=str,
|
|
metavar="EXPR",
|
|
help="""
|
|
a tuple containing the configuration of the Transformer layers
|
|
configurations:
|
|
[(input_dim,
|
|
num_heads,
|
|
ffn_dim,
|
|
normalize_before,
|
|
dropout,
|
|
attention_dropout,
|
|
relu_dropout), ]""",
|
|
)
|
|
parser.add_argument(
|
|
"--enc-output-dim",
|
|
type=int,
|
|
metavar="N",
|
|
help="encoder output dimension, projecting the LSTM output",
|
|
)
|
|
parser.add_argument(
|
|
"--in-channels",
|
|
type=int,
|
|
metavar="N",
|
|
help="number of encoder input channels",
|
|
)
|
|
parser.add_argument(
|
|
"--transformer-context",
|
|
type=str,
|
|
metavar="EXPR",
|
|
help="""
|
|
either None or a tuple of two ints, indicating left/right context a
|
|
transformer can have access to""",
|
|
)
|
|
parser.add_argument(
|
|
"--transformer-sampling",
|
|
type=str,
|
|
metavar="EXPR",
|
|
help="""
|
|
either None or a tuple of ints, indicating sampling factor in each layer""",
|
|
)
|
|
|
|
@classmethod
|
|
def build_model(cls, args, task):
|
|
"""Build a new model instance."""
|
|
base_architecture_enconly(args)
|
|
encoder = VGGTransformerEncoderOnly(
|
|
vocab_size=len(task.target_dictionary),
|
|
input_feat_per_channel=args.input_feat_per_channel,
|
|
vggblock_config=eval(args.vggblock_enc_config),
|
|
transformer_config=eval(args.transformer_enc_config),
|
|
encoder_output_dim=args.enc_output_dim,
|
|
in_channels=args.in_channels,
|
|
transformer_context=eval(args.transformer_context),
|
|
transformer_sampling=eval(args.transformer_sampling),
|
|
)
|
|
return cls(encoder)
|
|
|
|
def get_normalized_probs(self, net_output, log_probs, sample=None):
|
|
# net_output['encoder_out'] is a (T, B, D) tensor
|
|
lprobs = super().get_normalized_probs(net_output, log_probs, sample)
|
|
# lprobs is a (T, B, D) tensor
|
|
# we need to transoose to get (B, T, D) tensor
|
|
lprobs = lprobs.transpose(0, 1).contiguous()
|
|
lprobs.batch_first = True
|
|
return lprobs
|
|
|
|
|
|
class VGGTransformerEncoderOnly(VGGTransformerEncoder):
|
|
def __init__(
|
|
self,
|
|
vocab_size,
|
|
input_feat_per_channel,
|
|
vggblock_config=DEFAULT_ENC_VGGBLOCK_CONFIG,
|
|
transformer_config=DEFAULT_ENC_TRANSFORMER_CONFIG,
|
|
encoder_output_dim=512,
|
|
in_channels=1,
|
|
transformer_context=None,
|
|
transformer_sampling=None,
|
|
):
|
|
super().__init__(
|
|
input_feat_per_channel=input_feat_per_channel,
|
|
vggblock_config=vggblock_config,
|
|
transformer_config=transformer_config,
|
|
encoder_output_dim=encoder_output_dim,
|
|
in_channels=in_channels,
|
|
transformer_context=transformer_context,
|
|
transformer_sampling=transformer_sampling,
|
|
)
|
|
self.fc_out = Linear(self.encoder_output_dim, vocab_size)
|
|
|
|
def forward(self, src_tokens, src_lengths, **kwargs):
|
|
"""
|
|
src_tokens: padded tensor (B, T, C * feat)
|
|
src_lengths: tensor of original lengths of input utterances (B,)
|
|
"""
|
|
|
|
enc_out = super().forward(src_tokens, src_lengths)
|
|
x = self.fc_out(enc_out["encoder_out"])
|
|
# x = F.log_softmax(x, dim=-1)
|
|
# Note: no need this line, because model.get_normalized_prob will call
|
|
# log_softmax
|
|
return {
|
|
"encoder_out": x, # (T, B, C)
|
|
"encoder_padding_mask": enc_out["encoder_padding_mask"], # (T, B)
|
|
}
|
|
|
|
def max_positions(self):
|
|
"""Maximum input length supported by the encoder."""
|
|
return (1e6, 1e6) # an arbitrary large number
|
|
|
|
|
|
def Embedding(num_embeddings, embedding_dim, padding_idx):
|
|
m = nn.Embedding(num_embeddings, embedding_dim, padding_idx=padding_idx)
|
|
# nn.init.uniform_(m.weight, -0.1, 0.1)
|
|
# nn.init.constant_(m.weight[padding_idx], 0)
|
|
return m
|
|
|
|
|
|
def Linear(in_features, out_features, bias=True, dropout=0):
|
|
"""Linear layer (input: N x T x C)"""
|
|
m = nn.Linear(in_features, out_features, bias=bias)
|
|
# m.weight.data.uniform_(-0.1, 0.1)
|
|
# if bias:
|
|
# m.bias.data.uniform_(-0.1, 0.1)
|
|
return m
|
|
|
|
|
|
def LinearizedConv1d(in_channels, out_channels, kernel_size, dropout=0, **kwargs):
|
|
"""Weight-normalized Conv1d layer optimized for decoding"""
|
|
m = LinearizedConvolution(in_channels, out_channels, kernel_size, **kwargs)
|
|
std = math.sqrt((4 * (1.0 - dropout)) / (m.kernel_size[0] * in_channels))
|
|
nn.init.normal_(m.weight, mean=0, std=std)
|
|
nn.init.constant_(m.bias, 0)
|
|
return nn.utils.weight_norm(m, dim=2)
|
|
|
|
|
|
def LayerNorm(embedding_dim):
|
|
m = nn.LayerNorm(embedding_dim)
|
|
return m
|
|
|
|
|
|
# seq2seq models
|
|
def base_architecture(args):
|
|
args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 40)
|
|
args.vggblock_enc_config = getattr(
|
|
args, "vggblock_enc_config", DEFAULT_ENC_VGGBLOCK_CONFIG
|
|
)
|
|
args.transformer_enc_config = getattr(
|
|
args, "transformer_enc_config", DEFAULT_ENC_TRANSFORMER_CONFIG
|
|
)
|
|
args.enc_output_dim = getattr(args, "enc_output_dim", 512)
|
|
args.in_channels = getattr(args, "in_channels", 1)
|
|
args.tgt_embed_dim = getattr(args, "tgt_embed_dim", 128)
|
|
args.transformer_dec_config = getattr(
|
|
args, "transformer_dec_config", DEFAULT_ENC_TRANSFORMER_CONFIG
|
|
)
|
|
args.conv_dec_config = getattr(args, "conv_dec_config", DEFAULT_DEC_CONV_CONFIG)
|
|
args.transformer_context = getattr(args, "transformer_context", "None")
|
|
|
|
|
|
@register_model_architecture("asr_vggtransformer", "vggtransformer_1")
|
|
def vggtransformer_1(args):
|
|
args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 80)
|
|
args.vggblock_enc_config = getattr(
|
|
args, "vggblock_enc_config", "[(64, 3, 2, 2, True), (128, 3, 2, 2, True)]"
|
|
)
|
|
args.transformer_enc_config = getattr(
|
|
args,
|
|
"transformer_enc_config",
|
|
"((1024, 16, 4096, True, 0.15, 0.15, 0.15),) * 14",
|
|
)
|
|
args.enc_output_dim = getattr(args, "enc_output_dim", 1024)
|
|
args.tgt_embed_dim = getattr(args, "tgt_embed_dim", 128)
|
|
args.conv_dec_config = getattr(args, "conv_dec_config", "((256, 3, True),) * 4")
|
|
args.transformer_dec_config = getattr(
|
|
args,
|
|
"transformer_dec_config",
|
|
"((1024, 16, 4096, True, 0.15, 0.15, 0.15),) * 4",
|
|
)
|
|
|
|
|
|
@register_model_architecture("asr_vggtransformer", "vggtransformer_2")
|
|
def vggtransformer_2(args):
|
|
args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 80)
|
|
args.vggblock_enc_config = getattr(
|
|
args, "vggblock_enc_config", "[(64, 3, 2, 2, True), (128, 3, 2, 2, True)]"
|
|
)
|
|
args.transformer_enc_config = getattr(
|
|
args,
|
|
"transformer_enc_config",
|
|
"((1024, 16, 4096, True, 0.15, 0.15, 0.15),) * 16",
|
|
)
|
|
args.enc_output_dim = getattr(args, "enc_output_dim", 1024)
|
|
args.tgt_embed_dim = getattr(args, "tgt_embed_dim", 512)
|
|
args.conv_dec_config = getattr(args, "conv_dec_config", "((256, 3, True),) * 4")
|
|
args.transformer_dec_config = getattr(
|
|
args,
|
|
"transformer_dec_config",
|
|
"((1024, 16, 4096, True, 0.15, 0.15, 0.15),) * 6",
|
|
)
|
|
|
|
|
|
@register_model_architecture("asr_vggtransformer", "vggtransformer_base")
|
|
def vggtransformer_base(args):
|
|
args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 80)
|
|
args.vggblock_enc_config = getattr(
|
|
args, "vggblock_enc_config", "[(64, 3, 2, 2, True), (128, 3, 2, 2, True)]"
|
|
)
|
|
args.transformer_enc_config = getattr(
|
|
args, "transformer_enc_config", "((512, 8, 2048, True, 0.15, 0.15, 0.15),) * 12"
|
|
)
|
|
|
|
args.enc_output_dim = getattr(args, "enc_output_dim", 512)
|
|
args.tgt_embed_dim = getattr(args, "tgt_embed_dim", 512)
|
|
args.conv_dec_config = getattr(args, "conv_dec_config", "((256, 3, True),) * 4")
|
|
args.transformer_dec_config = getattr(
|
|
args, "transformer_dec_config", "((512, 8, 2048, True, 0.15, 0.15, 0.15),) * 6"
|
|
)
|
|
# Size estimations:
|
|
# Encoder:
|
|
# - vggblock param: 64*1*3*3 + 64*64*3*3 + 128*64*3*3 + 128*128*3 = 258K
|
|
# Transformer:
|
|
# - input dimension adapter: 2560 x 512 -> 1.31M
|
|
# - transformer_layers (x12) --> 37.74M
|
|
# * MultiheadAttention: 512*512*3 (in_proj) + 512*512 (out_proj) = 1.048M
|
|
# * FFN weight: 512*2048*2 = 2.097M
|
|
# - output dimension adapter: 512 x 512 -> 0.26 M
|
|
# Decoder:
|
|
# - LinearizedConv1d: 512 * 256 * 3 + 256 * 256 * 3 * 3
|
|
# - transformer_layer: (x6) --> 25.16M
|
|
# * MultiheadAttention (self-attention): 512*512*3 + 512*512 = 1.048M
|
|
# * MultiheadAttention (encoder-attention): 512*512*3 + 512*512 = 1.048M
|
|
# * FFN: 512*2048*2 = 2.097M
|
|
# Final FC:
|
|
# - FC: 512*5000 = 256K (assuming vocab size 5K)
|
|
# In total:
|
|
# ~65 M
|
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# CTC models
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def base_architecture_enconly(args):
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args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 40)
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args.vggblock_enc_config = getattr(
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args, "vggblock_enc_config", "[(32, 3, 2, 2, True)] * 2"
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)
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args.transformer_enc_config = getattr(
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args, "transformer_enc_config", "((256, 4, 1024, True, 0.2, 0.2, 0.2),) * 2"
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)
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args.enc_output_dim = getattr(args, "enc_output_dim", 512)
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args.in_channels = getattr(args, "in_channels", 1)
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args.transformer_context = getattr(args, "transformer_context", "None")
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args.transformer_sampling = getattr(args, "transformer_sampling", "None")
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@register_model_architecture("asr_vggtransformer_encoder", "vggtransformer_enc_1")
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def vggtransformer_enc_1(args):
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# vggtransformer_1 is the same as vggtransformer_enc_big, except the number
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# of layers is increased to 16
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# keep it here for backward compatiablity purpose
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args.input_feat_per_channel = getattr(args, "input_feat_per_channel", 80)
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args.vggblock_enc_config = getattr(
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args, "vggblock_enc_config", "[(64, 3, 2, 2, True), (128, 3, 2, 2, True)]"
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)
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args.transformer_enc_config = getattr(
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args,
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"transformer_enc_config",
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"((1024, 16, 4096, True, 0.15, 0.15, 0.15),) * 16",
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)
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args.enc_output_dim = getattr(args, "enc_output_dim", 1024)
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