Print the actual transcript. (GoogleCloudPlatform#601)

* Print the actual transcript. Also - print interim results as they come, overwriting them until you get the final result. * Fix test

Author: jerjou

speech/grpc/transcribe_streaming.py

@@ -19,6 +19,7 @@
 import contextlib
 import re
 import signal
+import sys
 import threading
 
 from google.cloud import credentials
@@ -131,13 +132,15 @@ def record_audio(rate, chunk):
 # [END audio_stream]
 
 
-def request_stream(data_stream, rate):
+def request_stream(data_stream, rate, interim_results=True):
  """Yields `StreamingRecognizeRequest`s constructed from a recording audio
  stream.
 
  Args:
  data_stream: A generator that yields raw audio data to send.
  rate: The sampling rate in hertz.
+ interim_results: Whether to return intermediate results, before the
+ transcription is finalized.
  """
  # The initial request must contain metadata about the stream, so the
  # server knows how to interpret it.
@@ -146,12 +149,12 @@ def request_stream(data_stream, rate):
  # https://goo.gl/KPZn97 for the full list.
  encoding='LINEAR16', # raw 16-bit signed LE samples
  sample_rate=rate, # the rate in hertz
- # See
- # https://g.co/cloud/speech/docs/best-practices#language_support
+ # See http://g.co/cloud/speech/docs/languages
  # for a list of supported languages.
  language_code='en-US', # a BCP-47 language tag
  )
  streaming_config = cloud_speech.StreamingRecognitionConfig(
+ interim_results=interim_results,
  config=recognition_config,
  )
 
@@ -164,21 +167,40 @@ def request_stream(data_stream, rate):
 
 
 def listen_print_loop(recognize_stream):
+ num_chars_printed = 0
  for resp in recognize_stream:
  if resp.error.code != code_pb2.OK:
  raise RuntimeError('Server error: ' + resp.error.message)
 
- # Display the transcriptions & their alternatives
- for result in resp.results:
- print(result.alternatives)
+ if not resp.results:
+ continue
 
- # Exit recognition if any of the transcribed phrases could be
- # one of our keywords.
- if any(re.search(r'\b(exit|quit)\b', alt.transcript, re.I)
- for result in resp.results
- for alt in result.alternatives):
- print('Exiting..')
- break
+ # Display the top transcription
+ result = resp.results[0]
+ transcript = result.alternatives[0].transcript
+
+ # Display interim results, but with a carriage return at the end of the
+ # line, so subsequent lines will overwrite them.
+ if not result.is_final:
+ # If the previous result was longer than this one, we need to print
+ # some extra spaces to overwrite the previous result
+ overwrite_chars = ' ' * max(0, num_chars_printed - len(transcript))
+
+ sys.stdout.write(transcript + overwrite_chars + '\r')
+ sys.stdout.flush()
+
+ num_chars_printed = len(transcript)
+
+ else:
+ print(transcript)
+
+ # Exit recognition if any of the transcribed phrases could be
+ # one of our keywords.
+ if re.search(r'\b(exit|quit)\b', transcript, re.I):
+ print('Exiting..')
+ break
+
+ num_chars_printed = 0
 
 
 def main():

speech/grpc/transcribe_streaming_test.py

@@ -62,4 +62,4 @@ def test_main(resource, monkeypatch, capsys):
  transcribe_streaming.main()
  out, err = capsys.readouterr()
 
- assert re.search(r'transcript.*"quit"', out, re.DOTALL | re.I)
+ assert re.search(r'quit', out, re.DOTALL | re.I)