Added Vosk API and updated README

README.rst

@@ -34,6 +34,8 @@ Speech recognition engine/API support:
 * `Houndify API <https://houndify.com/>`__
 * `IBM Speech to Text <http://www.ibm.com/smarterplanet/us/en/ibmwatson/developercloud/speech-to-text.html>`__
 * `Snowboy Hotword Detection <https://snowboy.kitt.ai/>`__ (works offline)
+* `Tensorflow <https://www.tensorflow.org/>`__
+* `Vosk API <https://github.com/alphacep/vosk-api/>`__ (works offline)
 
 **Quickstart:** ``pip install SpeechRecognition``. See the "Installing" section for more details.
 
@@ -86,6 +88,7 @@ To use all of the functionality of the library, you should have:
 * **PocketSphinx** (required only if you need to use the Sphinx recognizer, ``recognizer_instance.recognize_sphinx``)
 * **Google API Client Library for Python** (required only if you need to use the Google Cloud Speech API, ``recognizer_instance.recognize_google_cloud``)
 * **FLAC encoder** (required only if the system is not x86-based Windows/Linux/OS X)
+* **Vosk** (required only if you need to use Vosk API speech recognition ``recognizer_instance.recognize_vosk``)
 
 The following requirements are optional, but can improve or extend functionality in some situations:
 

speech_recognition/__init__.py

@@ -25,6 +25,9 @@
 __version__ = "3.8.1"
 __license__ = "BSD"
 
+# model for Vosk
+modelVosk = Model("model")
+
 try:  # attempt to use the Python 2 modules
     from urllib import urlencode
     from urllib2 import Request, urlopen, URLError, HTTPError
@@ -1390,7 +1393,37 @@ def recognize_tensorflow(self, audio_data, tensor_graph='tensorflow-data/conv_ac
             for node_id in top_k:
                 human_string = self.tflabels[node_id]
                 return human_string
+
+    def recognize_vosk(self, audio_data, language='en'):
+        from vosk import Model, KaldiRecognizer
+
+        if not os.path.exists("model"):
+            return "Please download the model from https://github.com/alphacep/vosk-api/blob/master/doc/models.md and unpack as 'model' in the current folder."
+            exit (1)
+
+        import pyaudio
+
+        rec = KaldiRecognizer(modelVosk, 16000)
+
+        p = pyaudio.PyAudio()
+        stream = p.open(format=pyaudio.paInt16, channels=1, rate=16000, input=True, frames_per_buffer=8000)
+        stream.start_stream()
+
+        while True:
+            data = stream.read(4000)
+            if len(data) == 0:
+                break
+            if rec.AcceptWaveform(data):
+                #bottom lines are for debugging
+                #print(rec.Result())
+                break
+            else:
+                #bottom lines are for debugging
+                #print(rec.PartialResult())
+                break
 
+        finalRecognition = rec.FinalResult()
+        return finalRecognition
 
 def get_flac_converter():
     """Returns the absolute path of a FLAC converter executable, or raises an OSError if none can be found."""