Encode audio file into cycle timings and emit tick opcodes. Amazingly,

even the naive opcode implementation works!

The main issue is that when we ACK, the speaker cone is allowed to tick
fully.  Maybe optimizing the ACK codepath to be fast enough will help
with this?

audio.py

@@ -0,0 +1,34 @@
+import numpy as np
+import librosa
+import soundfile as sf
+
+import opcodes
+import video
+
+
+class Audio:
+    def encode_audio(self, audio):
+        for a in audio:
+            yield opcodes.Tick(a)
+            yield opcodes.Tick(50-a)
+
+def main():
+    filename = librosa.util.example_audio_file()
+
+    data, samplerate = sf.read(filename, dtype='float32')
+    data = data.T
+    a = librosa.resample(data, samplerate, 20000).flatten()
+
+    a = librosa.util.normalize(a)
+    a = (a * 10 + 25).astype(np.int)
+
+    s = video.Video(frame_rate=None)
+    au = Audio()
+
+    with open("out.bin", "wb") as out:
+        out.write(bytes(s.emit_stream(au.encode_audio(a))))
+        out.write(bytes(s.done()))
+
+
+if __name__ == "__main__":
+    main()