Encapsulate things a bit

audio.py

@@ -4,10 +4,15 @@ import pyaudio
 import sys
 import time
 
-p = pyaudio.PyAudio()
+class Voice:
+    def __init__(self, frame_rate):
+        self.current_frame = 0
+        self.frame_rate = frame_rate
 
-current_frame = 0
-frame_rate = 44100
+    def generate(self, n):
+        data = make_frames(self.current_frame, n, self.frame_rate)
+        self.current_frame += n
+        return data
 
 def square(x, duty = 0.5):
     x1 = x % 1
@@ -26,7 +31,7 @@ def xsin(x):
 def A(t, level = 16384, decay_rate = 3):
     return level * math.exp(-decay_rate * t)
 
-def make_frames(k0, n):
+def make_frames(k0, n, frame_rate):
     f = 440
     T = 1 / frame_rate
     F = f / frame_rate
@@ -39,10 +44,14 @@ def make_frames(k0, n):
                 for k in range(k0, k0 + n))
     return data.tobytes()
 
+def main():
+    frame_rate = 44100
+
+    p = pyaudio.PyAudio()
+    v = Voice(frame_rate)
+
     def callback(in_data, frame_count, time_info, status):
-    global current_frame
-    data = make_frames(current_frame, frame_count)
-    current_frame += frame_count
+        data = v.generate(frame_count)
         return (data, pyaudio.paContinue)
 
     stream = p.open(format = pyaudio.paInt16,
@@ -60,3 +69,6 @@ stream.stop_stream()
     stream.close()
 
     p.terminate()
+
+if __name__ == '__main__':
+    main()