gnuradio-examples, gr-audio: moved audio Python and C++ examples into gr-audio

This begins a transition of examples from a separate gnuradio-examples component
into an examples directory with the component they go with.  In this commit:

gnuradio-examples/c++/audio/   => gr-audio/examples/c++
gnuradio-examples/python/audio => gr-audio/examples/python

The system installation directory remains $PREFIX/share/gnuradio/examples/audio

1 files changed, 68 insertions, 0 deletions

diff --git a/gr-audio/examples/python/spectrum_inversion.py b/gr-audio/examples/python/spectrum_inversion.py
new file mode 100755
index 000000000..021e23f2d
--- /dev/null
+++ b/gr-audio/examples/python/spectrum_inversion.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+#
+# Copyright 2004,2005,2007 Free Software Foundation, Inc.
+# 
+# This file is part of GNU Radio
+# 
+# GNU Radio is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3, or (at your option)
+# any later version.
+# 
+# GNU Radio is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+# 
+# You should have received a copy of the GNU General Public License
+# along with GNU Radio; see the file COPYING.  If not, write to
+# the Free Software Foundation, Inc., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+
+#
+# Gang - Here's a simple script that demonstrates spectrum inversion
+# using the multiply by [1,-1] method (mixing with Nyquist frequency).
+# Requires nothing but a sound card, and sounds just like listening
+# to a SSB signal on the wrong sideband.
+#
+
+from gnuradio import gr
+from gnuradio import audio
+from gnuradio.eng_option import eng_option
+from optparse import OptionParser
+
+class my_top_block(gr.top_block):
+
+    def __init__(self):
+        gr.top_block.__init__(self)
+
+        parser = OptionParser(option_class=eng_option)
+        parser.add_option("-I", "--audio-input", type="string", default="",
+                          help="pcm input device name.  E.g., hw:0,0 or /dev/dsp")
+        parser.add_option("-O", "--audio-output", type="string", default="",
+                          help="pcm output device name.  E.g., hw:0,0 or /dev/dsp")
+        parser.add_option("-r", "--sample-rate", type="eng_float", default=8000,
+                          help="set sample rate to RATE (8000)")
+        (options, args) = parser.parse_args ()
+        if len(args) != 0:
+            parser.print_help()
+            raise SystemExit, 1
+
+        sample_rate = int(options.sample_rate)
+        src = audio.source (sample_rate, options.audio_input)
+        dst = audio.sink (sample_rate, options.audio_output)
+
+	vec1 = [1, -1]
+	vsource = gr.vector_source_f(vec1, True)
+	multiply = gr.multiply_ff()
+
+	self.connect(src, (multiply, 0))
+	self.connect(vsource, (multiply, 1))
+	self.connect(multiply, dst)
+
+
+if __name__ == '__main__':
+    try:
+        my_top_block().run()
+    except KeyboardInterrupt:
+        pass