--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/service/audioInputLevels/audioInputLevelsAlsa.py	Fri Aug 02 07:55:45 2013 -0700
@@ -0,0 +1,59 @@
+from __future__ import division
+import argparse, alsaaudio, time, numpy, galena, socket
+
+def sendRecentAudio(accum, galenaOut, prefix):
+    samples = numpy.concatenate(accum)
+    samples = abs(samples / (1<<15))
+
+    galenaOut.send(prefix + '.avg', numpy.average(samples))
+    galenaOut.send(prefix + '.max', numpy.amax(samples))
+    
+def sendForever(card, prefix, periodSec, galenaOut):
+    inp = alsaaudio.PCM(alsaaudio.PCM_CAPTURE, alsaaudio.PCM_NORMAL, card)
+    inp.setchannels(1)
+    inp.setrate(44100)
+    inp.setformat(alsaaudio.PCM_FORMAT_S16_LE)
+    inp.setperiodsize(64)
+
+    readSleepSec = .05
+    lastSendTime = 0
+    accum = []
+    while True:
+
+        # I was getting machine hangs on an eeePC and I tried anything
+        # to make it not crash. I think this helped.
+        time.sleep(readSleepSec)
+
+        now = time.time()
+        if now - lastSendTime > periodSec * 2:
+            print "late: %s sec since last send and we have %s samples" % (
+                now - lastSendTime, sum(len(x) for x in accum))
+                
+        nframes, data = inp.read()
+        if nframes <= 0:
+            #print 'nframes', nframes, len(data)
+            continue # i get -32 a lot, don't know why
+        samples = numpy.fromstring(data, dtype=numpy.int16) 
+        accum.append(samples)
+
+        # -readSleepSec is in here to make sure we send a little too
+        # often (harmless) instead of missing a period sometimes,
+        # which makes a gap in the graph
+        if now > lastSendTime + periodSec - readSleepSec:
+            sendRecentAudio(accum, galenaOut, prefix)
+            lastSendTime = time.time()            
+
+            accum[:] = []
+
+parser = argparse.ArgumentParser()
+parser.add_argument(
+    '--card', required=True,
+    help='alsa card name (see list of unindented lines from `arecord -L`)')
+
+args = parser.parse_args()
+sendForever(
+    prefix='system.house.audio.%s' % socket.gethostname(),
+    periodSec=2,
+    card=args.card,
+    galenaOut=galena.Galena(host='bang'),
+)