minor fix doc

egs/librispeech/ASR/conv_emformer_transducer_stateless/stream.py

@@ -21,30 +21,10 @@ from typing import List, Optional, Tuple
 import k2
 import torch
 from beam_search import Hypothesis, HypothesisList
-from kaldifeat import FbankOptions, OnlineFbank, OnlineFeature
 
 from icefall.utils import AttributeDict
 
 
-def _create_streaming_feature_extractor() -> OnlineFeature:
-    """Create a CPU streaming feature extractor.
-
-    At present, we assume it returns a fbank feature extractor with
-    fixed options. In the future, we will support passing in the options
-    from outside.
-
-    Returns:
-      Return a CPU streaming feature extractor.
-    """
-    opts = FbankOptions()
-    opts.device = "cpu"
-    opts.frame_opts.dither = 0
-    opts.frame_opts.snip_edges = False
-    opts.frame_opts.samp_freq = 16000
-    opts.mel_opts.num_bins = 80
-    return OnlineFbank(opts)
-
-
 class Stream(object):
     def __init__(
         self,
@@ -57,6 +37,9 @@ class Stream(object):
         Args:
           params:
             It's the return value of :func:`get_params`.
+          decoding_graph:
+            The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
+            only when --decoding_method is fast_beam_search.
           device:
             The device to run this stream.
         """

egs/librispeech/ASR/conv_emformer_transducer_stateless/streaming_decode.py

@@ -466,6 +466,21 @@ def decode_one_chunk(
     params: AttributeDict,
     decoding_graph: Optional[k2.Fsa] = None,
 ) -> List[int]:
+    """
+    Args:
+      model:
+        The Transducer model.
+      streams:
+        A list of Stream objects.
+      params:
+        It is returned by :func:`get_params`.
+      decoding_graph:
+        The decoding graph. Can be either a `k2.trivial_graph` or HLG, Used
+        only when --decoding_method is fast_beam_search.
+
+    Returns:
+       A list of indexes indicating the finished streams.
+    """
     device = next(model.parameters()).device
 
     feature_list = []
@@ -529,6 +544,8 @@ def decode_one_chunk(
             beam=params.beam_size,
         )
     elif params.decoding_method == "fast_beam_search":
+        # feature_len is needed to get partial results.
+        # The rnnt_decoding_stream for fast_beam_search.
         fast_beam_search_one_best(
             model=model,
             streams=streams,