Created defaultInterpolator to speed up recv().

amodem/main.py

@@ -59,7 +59,8 @@ def recv(config, src, dst, dump_audio=None, pylab=None):
         gain = 1.0 / amplitude
         log.debug('Gain correction: %.3f', gain)
 
-        sampler = sampling.Sampler(signal, sampling.Interpolator(), freq=freq)
+        sampler = sampling.Sampler(signal, sampling.defaultInterpolator,
+                                   freq=freq)
         receiver.run(sampler, gain=1.0/amplitude, output=dst)
         return True
     except BaseException:

amodem/sampling.py

@@ -30,6 +30,9 @@ class Interpolator(object):
         assert len(self.filt) == resolution
 
 
+defaultInterpolator = Interpolator()
+
+
 class Sampler(object):
     def __init__(self, src, interp=None, freq=1.0):
         self.freq = freq