Add exception_on_overflow=False to pyaudio.Stream.read

This resolves some issues with reading streams on certain platforms (#59)
This also removes the read_divisor in favor of a wrapper for pyaudio which slightly simplifies the code

runner/precise_runner/runner.py

@@ -154,7 +154,6 @@ class PreciseRunner(object):
         self.on_prediction = on_prediction
         self.on_activation = on_activation
         self.chunk_size = engine.chunk_size
-        self.read_divisor = 1
 
         self.pa = None
         self.thread = None
@@ -163,18 +162,14 @@ class PreciseRunner(object):
         self.detector = TriggerDetector(self.chunk_size, sensitivity, trigger_level)
         atexit.register(self.stop)
 
-    def _calc_read_divisor(self):
+    def _wrap_stream_read(self, stream):
         """
         pyaudio.Stream.read takes samples as n, not bytes
-        so read(n) should be read(n // sample_depth
+        so read(n) should be read(n // sample_depth)
         """
-        try:
-            import pyaudio
-            if isinstance(self.stream, pyaudio.Stream):
-                return 2
-        except ImportError:
-            pass
-        return 1
+        import pyaudio
+        if getattr(stream.read, '__func__', None) is pyaudio.Stream.read:
+            stream.read = lambda x: pyaudio.Stream.read(stream, x // 2, False)
 
     def start(self):
         """Start listening from stream"""
@@ -185,7 +180,7 @@ class PreciseRunner(object):
                 16000, 1, paInt16, True, frames_per_buffer=self.chunk_size
             )
 
-        self.read_divisor = self._calc_read_divisor()
+        self._wrap_stream_read(self.stream)
 
         self.engine.start()
         self.running = True
@@ -219,7 +214,7 @@ class PreciseRunner(object):
     def _handle_predictions(self):
         """Continuously check Precise process output"""
         while self.running:
-            chunk = self.stream.read(self.chunk_size // self.read_divisor)
+            chunk = self.stream.read(self.chunk_size)
 
             if self.is_paused:
                 continue