ecasound 2.7.2 (2010) package. ubuntu's ecasound package is only at ecasound 2.2 way back from 2003. had to modify ecacontrol.py to use subprocess module instead of deprecated popen2

ecasound-2.7.2/examples/normalize.py

@@ -0,0 +1,67 @@
+#!/usr/local/bin/python
+
+# -----------------------------------------------------------------------
+# Example of an audio file volume normalizer (peak amplitude).
+# 
+# 1. Takes the filename to be processed from the command line.
+# 2. Runs the audio file through ecasound's volume analyzer.
+# 3. If the signal isn't normalized (gain factor > 1), it is amplified
+#    (gain factor from the analyzer) and the original file is replaced.
+# 4. Removes the temp file and exits.
+#
+# Known "bugs":
+#  - if ecasound's internal sample rate doesn't match audio file's
+#    sample rate, signal will get resampled twice
+#  - might change the audio format of the processed files
+# -----------------------------------------------------------------------
+
+import os
+import sys
+from tempfile import mktemp
+from pyeca import *
+
+# check arguments
+if len(sys.argv) < 2: sys.exit(-1)
+filename = sys.argv[1]
+if not os.path.isfile(filename): sys.exit(-1)
+tmpfile = mktemp(".wav")
+
+# create and configure the 'analyze' chainsetup
+e = ECA_CONTROL_INTERFACE()
+e.command("cs-add analyze")
+e.command("c-add 1")
+print "Normalizing file " + filename
+print "Using tempfile " + tmpfile
+e.command("ai-add " + filename)
+e.command("ao-add " + tmpfile)
+e.command("cop-add -ev")
+print "Analyzing sample data."
+e.command("cs-connect")
+e.command("run")
+e.command("cop-select 1")
+e.command("copp-select 2")
+e.command("copp-get") 
+gain_factor = e.last_float()
+e.command("cs-disconnect")
+if gain_factor <= 1:
+    print "File already normalized!"
+    sys.exit(0)
+
+# create and config the 'apply' chainsetup
+a = ECA_CONTROL_INTERFACE()
+a.command("cs-add apply")
+a.command("c-add 1")
+a.command("ai-add " + tmpfile)
+a.command("ao-add " + filename)
+print "Applying gain factor: ", gain_factor
+a.command("cop-add -ea:100")
+a.command("cop-select 1")
+a.command("copp-select 1")
+a.command_float_arg("copp-set", gain_factor * 100)
+a.command("cs-connect")
+a.command("run")
+
+# remove the tempfile and exit
+os.remove(tmpfile)
+print "Done!"
+sys.exit(0)