test can run

.notebook/python_test.ipynb

@@ -617,10 +617,52 @@
   },
   {
    "cell_type": "code",
-   "execution_count": null,
+   "execution_count": 58,
    "id": "pregnant-modem",
    "metadata": {},
    "outputs": [],
+   "source": [
+    "def get_default_args(fn):\n",
+    "    if fn is None:\n",
+    "        return {}\n",
+    "\n",
+    "    signature = inspect.signature(fn)\n",
+    "    return {\n",
+    "        k: v.default\n",
+    "        for k, v in signature.parameters.items()\n",
+    "        if v.default is not inspect.Parameter.empty\n",
+    "    }"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 59,
+   "id": "light-drill",
+   "metadata": {},
+   "outputs": [
+    {
+     "ename": "NameError",
+     "evalue": "name 'inspect' is not defined",
+     "output_type": "error",
+     "traceback": [
+      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
+      "\u001b[0;31mNameError\u001b[0m                                 Traceback (most recent call last)",
+      "\u001b[0;32m<ipython-input-59-8f782d06097f>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mget_default_args\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mio\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mopen\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
+      "\u001b[0;32m<ipython-input-58-cb5a8794f39f>\u001b[0m in \u001b[0;36mget_default_args\u001b[0;34m(fn)\u001b[0m\n\u001b[1;32m      3\u001b[0m         \u001b[0;32mreturn\u001b[0m \u001b[0;34m{\u001b[0m\u001b[0;34m}\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[1;32m      4\u001b[0m \u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0;32m----> 5\u001b[0;31m     \u001b[0msignature\u001b[0m \u001b[0;34m=\u001b[0m \u001b[0minspect\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0msignature\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0mfn\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      6\u001b[0m     return {\n\u001b[1;32m      7\u001b[0m         \u001b[0mk\u001b[0m\u001b[0;34m:\u001b[0m \u001b[0mv\u001b[0m\u001b[0;34m.\u001b[0m\u001b[0mdefault\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
+      "\u001b[0;31mNameError\u001b[0m: name 'inspect' is not defined"
+     ]
+    }
+   ],
+   "source": [
+    "get_default_args(io.open)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "protective-belgium",
+   "metadata": {},
+   "outputs": [],
    "source": []
   }
  ],

deepspeech/__init__.py

@@ -179,6 +179,11 @@ if not hasattr(paddle.Tensor, 'eq'):
     )
     paddle.Tensor.eq = eq
 
+if not hasattr(paddle, 'eq'):
+    logger.warn(
+        "override eq of paddle if exists or register, remove this when fixed!")
+    paddle.eq = eq
+
 
 def contiguous(xs: paddle.Tensor) -> paddle.Tensor:
     return xs
@@ -256,13 +261,14 @@ if not hasattr(paddle.Tensor, 'masked_fill'):
 
 def masked_fill_(xs: paddle.Tensor,
                  mask: paddle.Tensor,
-                 value: Union[float, int]):
+                 value: Union[float, int]) -> paddle.Tensor:
     assert is_broadcastable(xs.shape, mask.shape) is True
     bshape = paddle.broadcast_shape(xs.shape, mask.shape)
     mask = mask.broadcast_to(bshape)
     trues = paddle.ones_like(xs) * value
     ret = paddle.where(mask, trues, xs)
     paddle.assign(ret.detach(), output=xs)
+    return xs
 
 
 if not hasattr(paddle.Tensor, 'masked_fill_'):
@@ -271,9 +277,10 @@ if not hasattr(paddle.Tensor, 'masked_fill_'):
     paddle.Tensor.masked_fill_ = masked_fill_
 
 
-def fill_(xs: paddle.Tensor, value: Union[float, int]):
+def fill_(xs: paddle.Tensor, value: Union[float, int]) -> paddle.Tensor:
     val = paddle.full_like(xs, value)
     paddle.assign(val.detach(), output=xs)
+    return xs
 
 
 if not hasattr(paddle.Tensor, 'fill_'):
@@ -317,7 +324,7 @@ if not hasattr(paddle.Tensor, 'type_as'):
 
 def to(x: paddle.Tensor, *args, **kwargs) -> paddle.Tensor:
     assert len(args) == 1
-    if isinstace(args[0], str):  # dtype
+    if isinstance(args[0], str):  # dtype
         return x.astype(args[0])
     elif isinstance(args[0], paddle.Tensor):  #Tensor
         return x.astype(args[0].dtype)
@@ -338,6 +345,16 @@ if not hasattr(paddle.Tensor, 'float'):
     logger.warn("register user float to paddle.Tensor, remove this when fixed!")
     setattr(paddle.Tensor, 'float', func_float)
 
+
+def tolist(x: paddle.Tensor) -> List[Any]:
+    return x.numpy().tolist()
+
+
+if not hasattr(paddle.Tensor, 'tolist'):
+    logger.warn(
+        "register user tolist to paddle.Tensor, remove this when fixed!")
+    setattr(paddle.Tensor, 'tolist', tolist)
+
 ########### hcak paddle.nn.functional #############
 
 

deepspeech/exps/u2/model.py

@@ -13,6 +13,7 @@
 # limitations under the License.
 """Contains U2 model."""
 
+import sys
 import time
 import logging
 import numpy as np
@@ -256,11 +257,19 @@ class U2Tester(U2Trainer):
                 cutoff_prob=1.0,  # Cutoff probability for pruning.
                 cutoff_top_n=40,  # Cutoff number for pruning.
                 lang_model_path='models/lm/common_crawl_00.prune01111.trie.klm',  # Filepath for language model.
-                decoding_method='ctc_beam_search',  # Decoding method. Options: ctc_beam_search, ctc_greedy
+                decoding_method='attention',  # Decoding method. Options: 'attention', 'ctc_greedy_search',
+                # 'ctc_prefix_beam_search', 'attention_rescoring'
                 error_rate_type='wer',  # Error rate type for evaluation. Options `wer`, 'cer'
                 num_proc_bsearch=8,  # # of CPUs for beam search.
-                beam_size=500,  # Beam search width.
-                batch_size=128,  # decoding batch size
+                beam_size=10,  # Beam search width.
+                batch_size=16,  # decoding batch size
+                ctc_weight=0.0,  # ctc weight for attention rescoring decode mode.
+                decoding_chunk_size=-1,  # decoding chunk size. Defaults to -1.
+                # <0: for decoding, use full chunk.
+                # >0: for decoding, use fixed chunk size as set.
+                # 0: used for training, it's prohibited here. 
+                num_decoding_left_chunks=-1,  # number of left chunks for decoding. Defaults to -1.
+                simulate_streaming=False,  # simulate streaming inference. Defaults to False.
             ))
 
         if config is not None:
@@ -279,19 +288,19 @@ class U2Tester(U2Trainer):
             trans.append(''.join([chr(i) for i in ids]))
         return trans
 
-    def compute_metrics(self, audio, texts, audio_len, texts_len):
+    def compute_metrics(self, audio, audio_len, texts, texts_len, fout=None):
         cfg = self.config.decoding
         errors_sum, len_refs, num_ins = 0.0, 0, 0
         errors_func = error_rate.char_errors if cfg.error_rate_type == 'cer' else error_rate.word_errors
         error_rate_func = error_rate.cer if cfg.error_rate_type == 'cer' else error_rate.wer
 
-        vocab_list = self.test_loader.dataset.vocab_list
+        text_feature = self.test_loader.dataset.text_feature
 
         target_transcripts = self.ordid2token(texts, texts_len)
         result_transcripts = self.model.decode(
             audio,
             audio_len,
-            vocab_list,
+            text_feature=text_feature,
             decoding_method=cfg.decoding_method,
             lang_model_path=cfg.lang_model_path,
             beam_alpha=cfg.alpha,
@@ -299,13 +308,19 @@ class U2Tester(U2Trainer):
             beam_size=cfg.beam_size,
             cutoff_prob=cfg.cutoff_prob,
             cutoff_top_n=cfg.cutoff_top_n,
-            num_processes=cfg.num_proc_bsearch)
+            num_processes=cfg.num_proc_bsearch,
+            ctc_weight=cfg.ctc_weight,
+            decoding_chunk_size=cfg.decoding_chunk_size,
+            num_decoding_left_chunks=cfg.num_decoding_left_chunks,
+            simulate_streaming=cfg.simulate_streaming)
 
         for target, result in zip(target_transcripts, result_transcripts):
             errors, len_ref = errors_func(target, result)
             errors_sum += errors
             len_refs += len_ref
             num_ins += 1
+            if fout:
+                fout.write(result + "\n")
             self.logger.info(
                 "\nTarget Transcription: %s\nOutput Transcription: %s" %
                 (target, result))
@@ -322,6 +337,7 @@ class U2Tester(U2Trainer):
     @mp_tools.rank_zero_only
     @paddle.no_grad()
     def test(self):
+        assert self.args.result_file
         self.model.eval()
         self.logger.info(
             f"Test Total Examples: {len(self.test_loader.dataset)}")
@@ -329,13 +345,15 @@ class U2Tester(U2Trainer):
         error_rate_type = None
         errors_sum, len_refs, num_ins = 0.0, 0, 0
 
+        with open(self.args.result_file, 'w') as fout:
             for i, batch in enumerate(self.test_loader):
-            metrics = self.compute_metrics(*batch)
+                metrics = self.compute_metrics(*batch, fout=fout)
                 errors_sum += metrics['errors_sum']
                 len_refs += metrics['len_refs']
                 num_ins += metrics['num_ins']
                 error_rate_type = metrics['error_rate_type']
-            self.logger.info("Error rate [%s] (%d/?) = %f" %
+                self.logger.info(
+                    "Error rate [%s] (%d/?) = %f" %
                     (error_rate_type, num_ins, errors_sum / len_refs))
 
         # logging
@@ -351,24 +369,34 @@ class U2Tester(U2Trainer):
         try:
             self.test()
         except KeyboardInterrupt:
-            exit(-1)
+            sys.exit(-1)
 
-    def export(self):
+    def load_inferspec(self):
+        """infer model and input spec.
+
+        Returns:
+            nn.Layer: inference model
+            List[paddle.static.InputSpec]: input spec.
+        """
         from deepspeech.models.u2 import U2InferModel
         infer_model = U2InferModel.from_pretrained(self.test_loader.dataset,
                                                    self.config.model.clone(),
                                                    self.args.checkpoint_path)
-        infer_model.eval()
         feat_dim = self.test_loader.dataset.feature_size
-        static_model = paddle.jit.to_static(
-            infer_model,
-            input_spec=[
+        input_spec = [
             paddle.static.InputSpec(
                 shape=[None, feat_dim, None],
                 dtype='float32'),  # audio, [B,D,T]
             paddle.static.InputSpec(shape=[None],
                                     dtype='int64'),  # audio_length, [B]
-            ])
+        ]
+        return infer_model, input_spec
+
+    def export(self):
+        infer_model, input_spec = self.load_inferspec()
+        assert isinstance(input_spec, list), type(input_spec)
+        infer_model.eval()
+        static_model = paddle.jit.to_static(infer_model, input_spec=input_spec)
         logger.info(f"Export code: {static_model.forward.code}")
         paddle.jit.save(static_model, self.args.export_path)
 
@@ -376,7 +404,7 @@ class U2Tester(U2Trainer):
         try:
             self.export()
         except KeyboardInterrupt:
-            exit(-1)
+            sys.exit(-1)
 
     def setup(self):
         """Setup the experiment.

deepspeech/frontend/featurizer/speech_featurizer.py

@@ -107,8 +107,8 @@ class SpeechFeaturizer(object):
     def vocab_size(self):
         """Return the vocabulary size.
 
-        :return: Vocabulary size.
-        :rtype: int
+        Returns:
+            int: Vocabulary size.
         """
         return self._text_featurizer.vocab_size
 
@@ -116,16 +116,34 @@ class SpeechFeaturizer(object):
     def vocab_list(self):
         """Return the vocabulary in list.
 
-        :return: Vocabulary in list.
-        :rtype: list
+        Returns:
+            List[str]: 
         """
         return self._text_featurizer.vocab_list
 
+    @property
+    def vocab_dict(self):
+        """Return the vocabulary in dict.
+
+        Returns:
+            Dict[str, int]: 
+        """
+        return self._text_featurizer.vocab_dict
+
     @property
     def feature_size(self):
         """Return the audio feature size.
 
-        :return: audio feature size.
-        :rtype: int
+        Returns:
+            int: audio feature size.
         """
         return self._audio_featurizer.feature_size
+
+    @property
+    def text_feature(self):
+        """Return the text feature object.
+
+        Returns:
+            TextFeaturizer: object.
+        """
+        return self._text_featurizer

deepspeech/frontend/featurizer/text_featurizer.py

@@ -16,6 +16,7 @@
 import sentencepiece as spm
 
 from deepspeech.frontend.utility import UNK
+from deepspeech.frontend.utility import EOS
 
 
 class TextFeaturizer(object):
@@ -32,10 +33,12 @@ class TextFeaturizer(object):
             spm_model_prefix (str, optional): spm model prefix. Defaults to None.
         """
         assert unit_type in ('char', 'spm', 'word')
-        self.unk = UNK
         self.unit_type = unit_type
-        self._vocab_dict, self._vocab_list = self._load_vocabulary_from_file(
+        self._vocab_dict, self._id2token, self._vocab_list = self._load_vocabulary_from_file(
             vocab_filepath)
+        self.unk = UNK
+        self.unk_id = self._vocab_list.index(self.unk)
+        self.eos_id = self._vocab_list.index(EOS)
 
         if unit_type == 'spm':
             spm_model = spm_model_prefix + '.model'
@@ -51,14 +54,23 @@ class TextFeaturizer(object):
             tokens = self.spm_tokenize(text)
         return tokens
 
+    def detokenize(self, tokens):
+        if self.unit_type == 'char':
+            text = self.char_detokenize(tokens)
+        elif self.unit_type == 'word':
+            text = self.word_detokenize(tokens)
+        else:  # spm
+            text = self.spm_detokenize(tokens)
+        return text
+
     def featurize(self, text):
-        """Convert text string to a list of token indices in char-level.Note
-        that the token indexing order follows the given vocabulary file.
+        """Convert text string to a list of token indices.
 
-        :param text: Text to process.
-        :type text: str
-        :return: List of char-level token indices.
-        :rtype: List[int]
+        Args:
+            text (str): Text to process.
+        
+        Returns:
+            List[int]: List of token indices.
         """
         tokens = self.tokenize(text)
         ids = []
@@ -67,6 +79,24 @@ class TextFeaturizer(object):
             ids.append(self._vocab_dict[token])
         return ids
 
+    def defeaturize(self, idxs):
+        """Convert a list of token indices to text string,
+        ignore index after eos_id. 
+
+        Args:
+            idxs (List[int]): List of token indices.
+
+        Returns:
+            str: Text to process.
+        """
+        tokens = []
+        for idx in idxs:
+            if idx == self.eos_id:
+                break
+            tokens.append(self._id2token[idx])
+        text = self.detokenize(tokens)
+        return text
+
     @property
     def vocab_size(self):
         """Return the vocabulary size.
@@ -80,19 +110,50 @@ class TextFeaturizer(object):
     def vocab_list(self):
         """Return the vocabulary in list.
 
-        :return: Vocabulary in list.
-        :rtype: list
+        Returns:
+            List[str]: tokens.
         """
         return self._vocab_list
 
+    @property
+    def vocab_dict(self):
+        """Return the vocabulary in dict.
+
+        Returns:
+            Dict[str, int]: token str -> int
+        """
+        return self._vocab_dict
+
     def char_tokenize(self, text):
-        """Character tokenizer."""
+        """Character tokenizer.
+
+        Args:
+            text (str): text string.
+
+        Returns:
+            List[str]: tokens.
+        """
         return list(text.strip())
 
+    def char_detokenize(self, tokens):
+        """Character detokenizer.
+
+        Args:
+            tokens (List[str]): tokens.
+
+        Returns:
+           str: text string.
+        """
+        return "".join(tokens)
+
     def word_tokenize(self, text):
-        """Word tokenizer, spearte by <space>."""
+        """Word tokenizer, separate by <space>."""
         return text.strip().split()
 
+    def word_detokenize(self, tokens):
+        """Word detokenizer, separate by <space>."""
+        return " ".join(tokens)
+
     def spm_tokenize(self, text):
         """spm tokenize.
 
@@ -125,12 +186,34 @@ class TextFeaturizer(object):
         enc_line = encode_line(text)
         return enc_line
 
+    def spm_detokenize(self, tokens, input_format='piece'):
+        """spm detokenize.
+
+        Args:
+            ids (List[str]): tokens.
+
+        Returns:
+            str: text
+        """
+        if input_format == "piece":
+
+            def decode(l):
+                return "".join(self.sp.DecodePieces(l))
+        elif input_format == "id":
+
+            def decode(l):
+                return "".join(self.sp.DecodeIds(l))
+
+        return decode(tokens)
+
     def _load_vocabulary_from_file(self, vocab_filepath):
         """Load vocabulary from file."""
         vocab_lines = []
         with open(vocab_filepath, 'r', encoding='utf-8') as file:
             vocab_lines.extend(file.readlines())
         vocab_list = [line[:-1] for line in vocab_lines]
-        vocab_dict = dict(
-            [(token, id) for (id, token) in enumerate(vocab_list)])
-        return vocab_dict, vocab_list
+        id2token = dict(
+            [(idx, token) for (idx, token) in enumerate(vocab_list)])
+        token2id = dict(
+            [(token, idx) for (idx, token) in enumerate(vocab_list)])
+        return token2id, id2token, vocab_list

deepspeech/io/dataset.py

@@ -233,22 +233,20 @@ class ManifestDataset(Dataset):
 
     @property
     def vocab_size(self):
-        """Return the vocabulary size.
-
-        :return: Vocabulary size.
-        :rtype: int
-        """
         return self._speech_featurizer.vocab_size
 
     @property
     def vocab_list(self):
-        """Return the vocabulary in list.
-
-        :return: Vocabulary in list.
-        :rtype: list
-        """
         return self._speech_featurizer.vocab_list
 
+    @property
+    def vocab_dict(self):
+        return self._speech_featurizer.vocab_dict
+
+    @property
+    def text_feature(self):
+        return self._speech_featurizer.text_feature
+
     @property
     def feature_size(self):
         return self._speech_featurizer.feature_size

deepspeech/models/u2.py

@@ -16,10 +16,11 @@ Unified Streaming and Non-streaming Two-pass End-to-end Model for Speech Recogni
 (https://arxiv.org/pdf/2012.05481.pdf)
 """
 
+import sys
 from collections import defaultdict
 import logging
 from yacs.config import CfgNode
-from typing import List, Optional, Tuple
+from typing import List, Optional, Tuple, Dict
 
 import paddle
 from paddle import jit
@@ -132,6 +133,7 @@ class U2BaseModel(nn.Module):
             smoothing=lsm_weight,
             normalize_length=length_normalized_loss, )
 
+    @jit.export
     def forward(
             self,
             speech: paddle.Tensor,
@@ -158,7 +160,7 @@ class U2BaseModel(nn.Module):
         encoder_out, encoder_mask = self.encoder(speech, speech_lengths)
         #TODO(Hui Zhang): sum not support bool type
         #encoder_out_lens = encoder_mask.squeeze(1).sum(1)  #[B, 1, T] -> [B]
-        encoder_out_lens = encoder_mask.squeeze(1).astype(paddle.int64).sum(
+        encoder_out_lens = encoder_mask.squeeze(1).cast(paddle.int64).sum(
             1)  #[B, 1, T] -> [B]
 
         # 2a. Attention-decoder branch
@@ -301,14 +303,15 @@ class U2BaseModel(nn.Module):
         # log scale score
         scores = paddle.to_tensor(
             [0.0] + [-float('inf')] * (beam_size - 1), dtype=paddle.float)
-        scores = scores.to(device).repeat([batch_size]).unsqueeze(1).to(
+        scores = scores.to(device).repeat(batch_size).unsqueeze(1).to(
             device)  # (B*N, 1)
         end_flag = paddle.zeros_like(scores, dtype=paddle.bool)  # (B*N, 1)
         cache: Optional[List[paddle.Tensor]] = None
         # 2. Decoder forward step by step
         for i in range(1, maxlen + 1):
             # Stop if all batch and all beam produce eos
-            if end_flag.sum() == running_size:
+            # TODO(Hui Zhang): if end_flag.sum() == running_size:
+            if end_flag.cast(paddle.int64).sum() == running_size:
                 break
 
             # 2.1 Forward decoder step
@@ -333,7 +336,7 @@ class U2BaseModel(nn.Module):
             # regard top_k_index as (B*N*N),regard offset_k_index as (B*N),
             # then find offset_k_index in top_k_index
             base_k_index = paddle.arange(batch_size).view(-1, 1).repeat(
-                [1, beam_size])  # (B, N)
+                1, beam_size)  # (B, N)
             base_k_index = base_k_index * beam_size * beam_size
             best_k_index = base_k_index.view(-1) + offset_k_index.view(
                 -1)  # (B*N)
@@ -678,6 +681,108 @@ class U2BaseModel(nn.Module):
         decoder_out = paddle.nn.functional.log_softmax(decoder_out, dim=-1)
         return decoder_out
 
+    @paddle.no_grad()
+    def decode(self,
+               feats: paddle.Tensor,
+               feats_lengths: paddle.Tensor,
+               text_feature: Dict[str, int],
+               decoding_method: str,
+               lang_model_path: str,
+               beam_alpha: float,
+               beam_beta: float,
+               beam_size: int,
+               cutoff_prob: float,
+               cutoff_top_n: int,
+               num_processes: int,
+               ctc_weight: float=0.0,
+               decoding_chunk_size: int=-1,
+               num_decoding_left_chunks: int=-1,
+               simulate_streaming: bool=False):
+        """u2 decoding.
+
+        Args:
+            feats (Tenosr): audio features, (B, T, D)
+            feats_lengths (Tenosr): (B)
+            text_feature (TextFeaturizer): text feature object.
+            decoding_method (str): decoding mode, e.g. 
+                    'attention', 'ctc_greedy_search', 
+                    'ctc_prefix_beam_search', 'attention_rescoring'
+            lang_model_path (str): lm path.
+            beam_alpha (float): lm weight.
+            beam_beta (float): length penalty.
+            beam_size (int): beam size for search
+            cutoff_prob (float): for prune.
+            cutoff_top_n (int): for prune.
+            num_processes (int): 
+            ctc_weight (float, optional): ctc weight for attention rescoring decode mode. Defaults to 0.0.
+            decoding_chunk_size (int, optional): decoding chunk size. Defaults to -1.
+                    <0: for decoding, use full chunk.
+                    >0: for decoding, use fixed chunk size as set.
+                    0: used for training, it's prohibited here. 
+            num_decoding_left_chunks (int, optional): 
+                    number of left chunks for decoding. Defaults to -1.
+            simulate_streaming (bool, optional): simulate streaming inference. Defaults to False.
+
+        Raises:
+            ValueError: when not support decoding_method.
+        
+        Returns:
+            List[List[int]]: transcripts.
+        """
+        batch_size = feats.size(0)
+        if decoding_method in ['ctc_prefix_beam_search',
+                               'attention_rescoring'] and batch_size > 1:
+            logger.fatal(
+                f'decoding mode {decoding_method} must be running with batch_size == 1'
+            )
+            sys.exit(1)
+
+        if decoding_method == 'attention':
+            hyps = self.recognize(
+                feats,
+                feats_lengths,
+                beam_size=beam_size,
+                decoding_chunk_size=decoding_chunk_size,
+                num_decoding_left_chunks=num_decoding_left_chunks,
+                simulate_streaming=simulate_streaming)
+            hyps = [hyp.tolist() for hyp in hyps]
+        elif decoding_method == 'ctc_greedy_search':
+            hyps = self.ctc_greedy_search(
+                feats,
+                feats_lengths,
+                decoding_chunk_size=decoding_chunk_size,
+                num_decoding_left_chunks=num_decoding_left_chunks,
+                simulate_streaming=simulate_streaming)
+        # ctc_prefix_beam_search and attention_rescoring only return one
+        # result in List[int], change it to List[List[int]] for compatible
+        # with other batch decoding mode
+        elif decoding_method == 'ctc_prefix_beam_search':
+            assert feats.size(0) == 1
+            hyp = self.ctc_prefix_beam_search(
+                feats,
+                feats_lengths,
+                beam_size,
+                decoding_chunk_size=decoding_chunk_size,
+                num_decoding_left_chunks=num_decoding_left_chunks,
+                simulate_streaming=simulate_streaming)
+            hyps = [hyp]
+        elif decoding_method == 'attention_rescoring':
+            assert feats.size(0) == 1
+            hyp = self.attention_rescoring(
+                feats,
+                feats_lengths,
+                beam_size,
+                decoding_chunk_size=decoding_chunk_size,
+                num_decoding_left_chunks=num_decoding_left_chunks,
+                ctc_weight=ctc_weight,
+                simulate_streaming=simulate_streaming)
+            hyps = [hyp]
+        else:
+            raise ValueError(f"Not support decoding method: {decoding_method}")
+
+        res = [text_feature.defeaturize(hyp) for hyp in hyps]
+        return res
+
 
 class U2Model(U2BaseModel):
     def __init__(self, configs: dict):
@@ -779,14 +884,24 @@ class U2InferModel(U2Model):
     def __init__(self, configs: dict):
         super().__init__(configs)
 
-    def forward(self, audio, audio_len):
+    def forward(self,
+                feats,
+                feats_lengths,
+                decoding_chunk_size=-1,
+                num_decoding_left_chunks=-1,
+                simulate_streaming=False):
         """export model function
 
         Args:
-            audio (Tensor): [B, T, D]
-            audio_len (Tensor): [B]
+            feats (Tensor): [B, T, D]
+            feats_lengths (Tensor): [B]
 
         Returns:
-            probs: probs after softmax
+            List[List[int]]: best path result
         """
-        raise NotImplementedError("U2Model infer")
+        return self.ctc_greedy_search(
+            feats,
+            feats_lengths,
+            decoding_chunk_size=decoding_chunk_size,
+            num_decoding_left_chunks=num_decoding_left_chunks,
+            simulate_streaming=simulate_streaming)

deepspeech/modules/ctc.py

@@ -224,9 +224,28 @@ class CTCDecoder(nn.Layer):
     def decode_probs(self, probs, logits_lens, vocab_list, decoding_method,
                      lang_model_path, beam_alpha, beam_beta, beam_size,
                      cutoff_prob, cutoff_top_n, num_processes):
-        """ probs: activation after softmax 
-        logits_len: audio output lens
+        """ctc decoding with probs.
+
+        Args:
+            probs (Tenosr): activation after softmax 
+            logits_lens (Tenosr): audio output lens
+            vocab_list ([type]): [description]
+            decoding_method ([type]): [description]
+            lang_model_path ([type]): [description]
+            beam_alpha ([type]): [description]
+            beam_beta ([type]): [description]
+            beam_size ([type]): [description]
+            cutoff_prob ([type]): [description]
+            cutoff_top_n ([type]): [description]
+            num_processes ([type]): [description]
+
+        Raises:
+            ValueError: when decoding_method not support.
+
+        Returns:
+            List[str]: transcripts.
         """
+
         probs_split = [probs[i, :l, :] for i, l in enumerate(logits_lens)]
         if decoding_method == "ctc_greedy":
             result_transcripts = self._decode_batch_greedy(

deepspeech/modules/decoder.py

@@ -176,5 +176,5 @@ class TransformerDecoder(nn.Module):
         else:
             y = x[:, -1]
         if self.use_output_layer:
-            y = paddle.log_softmax(self.output_layer(y), dim=-1)
+            y = paddle.log_softmax(self.output_layer(y), axis=-1)
         return y, new_cache

deepspeech/modules/decoder_layer.py

@@ -101,12 +101,17 @@ class DecoderLayer(nn.Module):
             tgt_q_mask = tgt_mask
         else:
             # compute only the last frame query keeping dim: max_time_out -> 1
-            assert cache.shape == (
-                tgt.shape[0], tgt.shape[1] - 1, self.size,
-            ), "{cache.shape} == {(tgt.shape[0], tgt.shape[1] - 1, self.size)}"
+            assert cache.shape == [
+                tgt.shape[0],
+                tgt.shape[1] - 1,
+                self.size,
+            ], f"{cache.shape} == {[tgt.shape[0], tgt.shape[1] - 1, self.size]}"
             tgt_q = tgt[:, -1:, :]
             residual = residual[:, -1:, :]
-            tgt_q_mask = tgt_mask[:, -1:, :]
+            # TODO(Hui Zhang): slice not support bool type
+            # tgt_q_mask = tgt_mask[:, -1:, :]
+            tgt_q_mask = tgt_mask.cast(paddle.int64)[:, -1:, :].cast(
+                paddle.bool)
 
         if self.concat_after:
             tgt_concat = paddle.cat(

deepspeech/modules/mask.py

@@ -41,6 +41,7 @@ def sequence_mask(x_len, max_len=None, dtype='float32'):
         [[1., 1., 0., 0.],
          [1., 1., 1., 1.]]
     """
+    assert x_len.dim() == 1
     max_len = max_len or x_len.max()
     x_len = paddle.unsqueeze(x_len, -1)
     row_vector = paddle.arange(max_len)
@@ -65,6 +66,7 @@ def make_pad_mask(lengths: paddle.Tensor) -> paddle.Tensor:
                  [0, 0, 0, 1, 1],
                  [0, 0, 1, 1, 1]]
     """
+    assert lengths.dim() == 1
     batch_size = int(lengths.shape[0])
     max_len = int(lengths.max())
     seq_range = paddle.arange(0, max_len, dtype=paddle.int64)

deepspeech/training/cli.py

@@ -57,6 +57,9 @@ def default_argument_parser():
     # save jit model to 
     parser.add_argument("--export_path", type=str, help="path of the jit model to save")
 
+    # save asr result to 
+    parser.add_argument("--result_file", type=str, help="path of save the asr result")
+
     # running
     parser.add_argument("--device", type=str, default='gpu', choices=["cpu", "gpu"],
                         help="device type to use, cpu and gpu are supported.")

examples/tiny/s1/conf/conformer.yaml

@@ -126,16 +126,24 @@ training:
     lr_decay: 1.0
   log_interval: 100
 
+
 decoding:
-  batch_size: 128
+  batch_size: 16
   error_rate_type: wer
-  decoding_method: ctc_beam_search
+  decoding_method: attention  # 'attention', 'ctc_greedy_search', 'ctc_prefix_beam_search', 'attention_rescoring'
   lang_model_path: data/lm/common_crawl_00.prune01111.trie.klm
   alpha: 2.5
   beta: 0.3
-  beam_size: 500
+  beam_size: 10
   cutoff_prob: 1.0
-  cutoff_top_n: 40
+  cutoff_top_n: 0
   num_proc_bsearch: 8
+  ctc_weight: 0.0 # ctc weight for attention rescoring decode mode.
+  decoding_chunk_size: -1 # decoding chunk size. Defaults to -1.
+      # <0: for decoding, use full chunk.
+      # >0: for decoding, use fixed chunk size as set.
+      # 0: used for training, it's prohibited here. 
+  num_decoding_left_chunks: -1  # number of left chunks for decoding. Defaults to -1.
+  simulate_streaming: False  # simulate streaming inference. Defaults to False.
 
 

examples/tiny/s1/local/test.sh

@@ -11,6 +11,7 @@ python3 -u ${BIN_DIR}/test.py \
 --device 'gpu' \
 --nproc 1 \
 --config conf/conformer.yaml \
+--result_file data/asr.result \
 --output ckpt
 
 if [ $? -ne 0 ]; then

tests/mask_test.py

@@ -17,14 +17,23 @@ import numpy as np
 import unittest
 from deepspeech.modules.mask import sequence_mask
 from deepspeech.modules.mask import make_non_pad_mask
+from deepspeech.modules.mask import make_pad_mask
 
 
 class TestU2Model(unittest.TestCase):
     def setUp(self):
         paddle.set_device('cpu')
         self.lengths = paddle.to_tensor([5, 3, 2])
-        self.masks = np.array(
-            [[1, 1, 1, 1, 1], [1, 1, 1, 0, 0], [1, 1, 0, 0, 0]], )
+        self.masks = np.array([
+            [1, 1, 1, 1, 1],
+            [1, 1, 1, 0, 0],
+            [1, 1, 0, 0, 0],
+        ])
+        self.pad_masks = np.array([
+            [0, 0, 0, 0, 0],
+            [0, 0, 0, 1, 1],
+            [0, 0, 1, 1, 1],
+        ])
 
     def test_sequence_mask(self):
         res = sequence_mask(self.lengths)
@@ -32,7 +41,13 @@ class TestU2Model(unittest.TestCase):
 
     def test_make_non_pad_mask(self):
         res = make_non_pad_mask(self.lengths)
+        res1 = sequence_mask(self.lengths)
         self.assertSequenceEqual(res.numpy().tolist(), self.masks.tolist())
+        self.assertSequenceEqual(res.numpy().tolist(), res1.numpy().tolist())
+
+    def test_make_pad_mask(self):
+        res = make_pad_mask(self.lengths)
+        self.assertSequenceEqual(res.numpy().tolist(), self.pad_masks.tolist())
 
 
 if __name__ == '__main__':