gr-vocoder: re-implemented gr-cvsd-vocoder in gr-vocoder

19 files changed, 1113 insertions, 7 deletions

diff --git a/gr-vocoder/examples/Makefile.am b/gr-vocoder/examples/Makefile.am
index 7e069865d..d325ae095 100644
--- a/gr-vocoder/examples/Makefile.am
+++ b/gr-vocoder/examples/Makefile.am
@@ -24,6 +24,5 @@ include $(top_srcdir)/Makefile.common
 ourdatadir = $(exampledir)/vocoder
 
 dist_ourdata_SCRIPTS = \
+	cvsd_audio_loopback.py \
 	gsm_audio_loopback.py
-
-
diff --git a/gr-vocoder/examples/cvsd_audio_loopback.py b/gr-vocoder/examples/cvsd_audio_loopback.py
new file mode 100755
index 000000000..7f2a00dbf
--- /dev/null
+++ b/gr-vocoder/examples/cvsd_audio_loopback.py
@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+#
+# Copyright 2007,2011 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.
+# 
+
+from gnuradio import gr, blks2
+from gnuradio import audio
+from gnuradio import vocoder
+
+def build_graph():
+    sample_rate = 8000
+    scale_factor = 32000
+    
+    tb = gr.top_block()
+    src = audio.source(sample_rate, "plughw:0,0")
+    src_scale = gr.multiply_const_ff(scale_factor)
+
+    interp = blks2.rational_resampler_fff(8, 1)
+    f2s = gr.float_to_short ()
+
+    enc = vocoder.cvsd_encode_sb()
+    dec = vocoder.cvsd_decode_bs()
+
+    s2f = gr.short_to_float ()
+    decim = blks2.rational_resampler_fff(1, 8)
+
+    sink_scale = gr.multiply_const_ff(1.0/scale_factor)
+    sink = audio.sink(sample_rate, "plughw:0,0")
+
+    tb.connect(src, src_scale, interp, f2s, enc)
+    tb.connect(enc, dec, s2f, decim, sink_scale, sink)
+
+    if 0: # debug
+        tb.conect(src, gr.file_sink(gr.sizeof_float, "source.dat"))
+        tb.conect(src_scale, gr.file_sink(gr.sizeof_float, "src_scale.dat"))
+        tb.conect(interp, gr.file_sink(gr.sizeof_float, "interp.dat"))
+        tb.conect(f2s, gr.file_sink(gr.sizeof_short, "f2s.dat"))
+        tb.conect(enc, gr.file_sink(gr.sizeof_char,  "enc.dat"))
+        tb.conect(dec, gr.file_sink(gr.sizeof_short, "dec.dat"))
+        tb.conect(s2f, gr.file_sink(gr.sizeof_float, "s2f.dat"))
+        tb.conect(decim, gr.file_sink(gr.sizeof_float, "decim.dat"))
+        tb.conect(sink_scale, gr.file_sink(gr.sizeof_float, "sink_scale.dat"))
+        
+    return tb
+
+if __name__ == '__main__':
+    tb = build_graph()
+    tb.start()
+    raw_input ('Press Enter to exit: ')
+    tb.stop()
+    tb.wait()
diff --git a/gr-vocoder/examples/gsm_audio_loopback.py b/gr-vocoder/examples/gsm_audio_loopback.py
index 9904944ce..f4e96f471 100755
--- a/gr-vocoder/examples/gsm_audio_loopback.py
+++ b/gr-vocoder/examples/gsm_audio_loopback.py
@@ -42,3 +42,4 @@ if __name__ == '__main__':
     tb.start()
     raw_input ('Press Enter to exit: ')
     tb.stop()
+    tb.wait()
diff --git a/gr-vocoder/include/Makefile.am b/gr-vocoder/include/Makefile.am
index 71c56d47f..7ec9f6382 100644
--- a/gr-vocoder/include/Makefile.am
+++ b/gr-vocoder/include/Makefile.am
@@ -23,5 +23,7 @@ include $(top_srcdir)/Makefile.common
 
 # C/C++ headers get installed in ${prefix}/include/gnuradio
 grinclude_HEADERS = \
+	vocoder_cvsd_decode_bs.h \
+	vocoder_cvsd_encode_sb.h \
 	vocoder_gsm_fr_decode_ps.h \
 	vocoder_gsm_fr_encode_sp.h
diff --git a/gr-vocoder/include/vocoder_cvsd_decode_bs.h b/gr-vocoder/include/vocoder_cvsd_decode_bs.h
new file mode 100644
index 000000000..dd588c661
--- /dev/null
+++ b/gr-vocoder/include/vocoder_cvsd_decode_bs.h
@@ -0,0 +1,171 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2011 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.
+ */
+
+#ifndef INCLUDED_VOCODER_CVSD_DECODE_BS_H
+#define INCLUDED_VOCODER_CVSD_DECODE_BS_H
+
+#include <gr_sync_interpolator.h>
+
+class vocoder_cvsd_decode_bs;
+
+typedef boost::shared_ptr<vocoder_cvsd_decode_bs> vocoder_cvsd_decode_bs_sptr;
+
+ /*!
+  * \brief Constructor parameters to initialize the CVSD decoder.  The default
+  * values are modeled after the Bluetooth standard and should not be changed,
+  * except by an advanced user
+  *
+  * \param min_step       Minimum step size used to update the internal reference.  Default: "10"
+  * \param max_step       Maximum step size used to update the internal reference.  Default: "1280"
+  * \param step_decay     Decay factor applied to step size when there is not a run of J output 1s or 0s.  Default: "0.9990234375"  (i.e. 1-1/1024)
+  * \param accum_decay    Decay factor applied to the internal reference during every interation of the codec.  Default: "0.96875"  (i.e. 1-1/32)
+  * \param K;             Size of shift register; the number of output bits remembered by codec (must be less or equal to 32).  Default: "32"
+  * \param J;             Number of bits in the shift register that are equal; i.e. the size of a run of 1s, 0s. Default: "4"
+  * \param pos_accum_max  Maximum integer value allowed for the internal reference.  Default: "32767" (2^15 - 1 or MAXSHORT)
+  * \param neg_accum_max  Minimum integer value allowed for the internal reference.  Default: "-32767" (-2^15 + 1 or MINSHORT+1)
+  *
+  */
+vocoder_cvsd_decode_bs_sptr vocoder_make_cvsd_decode_bs (short min_step=10,
+							 short max_step=1280,
+							 double step_decay=0.9990234375,
+							 double accum_decay= 0.96875,
+							 int K=32,
+							 int J=4,
+							 short pos_accum_max=32767,
+							 short neg_accum_max=-32767);
+
+/*!
+ * \brief This block performs CVSD audio decoding.  Its design and implementation
+ * is modeled after the CVSD encoder/decoder specifications defined in the
+ * Bluetooth standard.
+ *
+ * \ingroup vocoder_blk
+ *
+ * CVSD is a method for encoding speech that seeks to reduce the
+ * bandwidth required for digital voice transmission.  CVSD takes
+ * advantage of strong correlation between samples, quantizing the
+ * difference in amplitude between two consecutive samples.  This
+ * difference requires fewer quantization levels as compared to other
+ * methods that quantize the actual amplitude level, reducing the
+ * bandwidth.  CVSD employs a two level quantizer (one bit) and an
+ * adaptive algorithm that allows for continuous step size adjustment.
+ *
+ * The coder can represent low amplitude signals with accuracy without
+ * sacrificing performance on large amplitude signals, a trade off that
+ * occurs in some non-adaptive modulations.
+ *
+ * The CVSD decoder effectively provides 1-to-8 decompression.  More
+ * specifically, for each incoming input bit, the decoder outputs one
+ * audio sample.  If the input is a "1" bit, the internal reference is
+ * increased appropriately and then outputted as the next estimated audio
+ * sample.  If the input is a "0" bit, the internal reference is
+ * decreased appropriately and then likewise outputted as the next estimated
+ * audio sample.  Grouping 8 input bits together, the encoder essentially
+ * produces 8 output audio samples for everyone one input byte.
+ *
+ * This decoder requires that output audio samples are 2-byte short signed
+ * integers.  The result bandwidth conversion, therefore, is 1 byte of
+ * encoded audio data to 16 output bytes of raw audio data.
+ *
+ * The CVSD decoder module must be post-fixed by a down-converter to
+ * under-sample the audio data after decoding.  The Bluetooth standard
+ * specifically calls for a 8-to-1 decimating down-converter.  This is
+ * required so that so that output sampling rate equals the original input
+ * sampling rate present before the encoder.  In all cases, the output
+ * down-converter rate must be the inverse of the input up-converter rate
+ * before the CVSD encoder.
+ *
+ * References:
+ * 1.  Continuously Variable Slope Delta Modulation (CVSD) A Tutorial,
+ *         Available: http://www.eetkorea.com/ARTICLES/2003AUG/A/2003AUG29_NTEK_RFD_AN02.PDF.
+ * 2.  Specification of The Bluetooth System
+ *         Available: http://grouper.ieee.org/groups/802/15/Bluetooth/core_10_b.pdf.
+ * 3.  McGarrity, S., Bluetooth Full Duplex Voice and Data Transmission. 2002.
+ *         Bluetooth Voice Simulink® Model, Available:
+ *         http://www.mathworks.com/company/newsletters/digest/nov01/bluetooth.html
+ *
+ */
+
+class vocoder_cvsd_decode_bs : public gr_sync_interpolator
+{
+private:
+  friend vocoder_cvsd_decode_bs_sptr vocoder_make_cvsd_decode_bs (short min_step,
+								  short max_step,
+								  double step_decay,
+								  double accum_decay,
+								  int K,
+								  int J,
+								  short pos_accum_max,
+								  short neg_accum_max);
+
+  vocoder_cvsd_decode_bs (short min_step, short max_step, double step_decay,
+			  double accum_decay, int K, int J,
+			  short pos_accum_max, short neg_accum_max);
+
+  //! Member functions required by the encoder/decoder
+  //! \brief Rounding function specific to CVSD
+  //! \return the input value rounded to the nearest integer
+  int cvsd_round(double input);
+  
+  //! \brief A power function specific to CVSD data formats
+  //! \return (radix)^power, where radix and power are short integers
+  unsigned int cvsd_pow (short radix, short power);
+ 
+  //! \brief Sums number of 1's in the input
+  //! \return the number of 1s in the four bytes of an input unsigned integer
+  unsigned char cvsd_bitwise_sum (unsigned int input);
+
+  short d_min_step;
+  short d_max_step;
+  double d_step_decay;
+  double d_accum_decay;
+
+  int d_K;  //!< \brief Size of shift register; the number of output bits remembered in shift register
+  int d_J;  //!< \brief Number of bits in the shift register that are equal; size of run of 1s, 0s
+
+  short d_pos_accum_max;
+  short d_neg_accum_max;
+
+  int d_accum;                //!< \brief Current value of internal reference
+  int d_loop_counter;         //!< \brief Current value of the loop counter
+  unsigned int d_runner;      //!< \brief Current value of the shift register
+  unsigned int d_runner_mask; //!< \brief Value of the mask to access the last J bits of the shift register
+  short d_stepsize;           //!< \brief Current value of the step sizer
+
+ public:
+  ~vocoder_cvsd_decode_bs ();	// public destructor
+
+  short min_step() { return d_min_step; }
+  short max_step() { return d_max_step; }
+  double step_decay() { return d_step_decay; }
+  double accum_decay() { return d_accum_decay; }
+  int K() { return d_K; }
+  int J() { return d_J; }
+  short pos_accum_max() { return d_pos_accum_max; }
+  short neg_accum_max() { return d_neg_accum_max; }
+
+  int work (int noutput_items,
+	    gr_vector_const_void_star &input_items,
+	    gr_vector_void_star &output_items);
+};
+
+#endif /* INCLUDED_VOCODER_CVSD_DECODE_BS_H */
diff --git a/gr-vocoder/include/vocoder_cvsd_encode_sb.h b/gr-vocoder/include/vocoder_cvsd_encode_sb.h
new file mode 100644
index 000000000..da09b3927
--- /dev/null
+++ b/gr-vocoder/include/vocoder_cvsd_encode_sb.h
@@ -0,0 +1,173 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 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.
+ */
+#ifndef INCLUDED_VOCODER_CVSD_ENCODER_SB_H
+#define INCLUDED_VOCODER_CVSD_ENCODER_SB_H
+
+#include <gr_sync_decimator.h>
+
+class vocoder_cvsd_encode_sb;
+
+typedef boost::shared_ptr<vocoder_cvsd_encode_sb> vocoder_cvsd_encode_sb_sptr;
+
+ /*!
+  * \brief Constructor parameters to initialize the CVSD encoder.  The default
+  * values are modeled after the Bluetooth standard and should not be changed
+  * except by an advanced user
+  *
+  * \param min_step       Minimum step size used to update the internal reference.  Default: "10"
+  * \param max_step       Maximum step size used to update the internal reference.  Default: "1280"
+  * \param step_decay     Decay factor applied to step size when there is not a run of J output 1s or 0s.  Default: "0.9990234375"  (i.e. 1-1/1024)
+  * \param accum_decay    Decay factor applied to the internal reference during every interation of the codec.  Default: "0.96875"  (i.e. 1-1/32)
+  * \param K;             Size of shift register; the number of output bits remembered by codec (must be less or equal to 32).  Default: "32"
+  * \param J;             Number of bits in the shift register that are equal; i.e. the size of a run of 1s, 0s. Default: "4"
+  * \param pos_accum_max  Maximum integer value allowed for the internal reference.  Default: "32767" (2^15 - 1 or MAXSHORT)
+  * \param neg_accum_max  Minimum integer value allowed for the internal reference.  Default: "-32767" (-2^15 + 1 or MINSHORT+1)
+  *
+  */
+
+vocoder_cvsd_encode_sb_sptr vocoder_make_cvsd_encode_sb(short min_step=10,
+							short max_step=1280,
+							double step_decay=0.9990234375,
+							double accum_decay= 0.96875,
+							int K=32,
+							int J=4,
+							short pos_accum_max=32767,
+							short neg_accum_max=-32767);
+
+/*!
+ * \brief This block performs CVSD audio encoding.  Its design and implementation
+ * is modeled after the CVSD encoder/decoder specifications defined in the
+ * Bluetooth standard.
+ *
+ * \ingroup vocoder_blk
+ *
+ * CVSD is a method for encoding speech that seeks to reduce the
+ * bandwidth required for digital voice transmission.  CVSD takes
+ * advantage of strong correlation between samples, quantizing the
+ * difference in amplitude between two consecutive samples.  This
+ * difference requires fewer quantization levels as compared to other
+ * methods that quantize the actual amplitude level, reducing the
+ * bandwidth.  CVSD employs a two level quantizer (one bit) and an
+ * adaptive algorithm that allows for continuous step size adjustment.
+ *
+ * The coder can represent low amplitude signals with accuracy without
+ * sacrificing performance on large amplitude signals, a trade off that
+ * occurs in some non-adaptive modulations.
+ *
+ * The CVSD encoder effectively provides 8-to-1 compression.  More
+ * specifically, each incoming audio sample is compared to an internal
+ * reference value.  If the input is greater or equal to the reference,
+ * the encoder outputs a "1" bit.  If the input is less than the reference,
+ * the encoder outputs a "0" bit.  The reference value is then updated
+ * accordingly based on the frequency of outputted "1" or "0" bits.  By
+ * grouping 8 outputs bits together, the encoder essentially produce one
+ * output byte for every 8 input audio samples.
+ *
+ * This encoder requires that input audio samples are 2-byte short signed
+ * integers.  The result bandwidth conversion, therefore, is 16 input bytes
+ * of raw audio data to 1 output byte of encoded audio data.
+ *
+ * The CVSD encoder module must be prefixed by an up-converter to over-sample
+ * the audio data prior to encoding.  The Bluetooth standard specifically
+ * calls for a 1-to-8 interpolating up-converter.  While this reduces the
+ * overall compression of the codec, this is required so that the encoder
+ * can accurately compute the slope between adjacent audio samples and
+ * correctly update its internal reference value.
+ *
+ * References:
+ *
+ * 1.  Continuously Variable Slope Delta Modulation (CVSD) A Tutorial,
+ *     Available: http://www.eetkorea.com/ARTICLES/2003AUG/A/2003AUG29_NTEK_RFD_AN02.PDF.
+ *
+ * 2.  Specification of The Bluetooth System
+ *     Available: http://grouper.ieee.org/groups/802/15/Bluetooth/core_10_b.pdf.
+ *
+ * 3.  McGarrity, S., Bluetooth Full Duplex Voice and Data Transmission. 2002.
+ *     Bluetooth Voice Simulink® Model, Available:
+ *     http://www.mathworks.com/company/newsletters/digest/nov01/bluetooth.html
+ *
+ */
+
+class vocoder_cvsd_encode_sb : public gr_sync_decimator
+{
+private:
+  friend vocoder_cvsd_encode_sb_sptr vocoder_make_cvsd_encode_sb(short min_step,
+								 short max_step,
+								 double step_decay,
+								 double accum_decay,
+								 int K,
+								 int J,
+								 short pos_accum_max,
+								 short neg_accum_max);
+
+  vocoder_cvsd_encode_sb(short min_step, short max_step, double step_decay,
+			 double accum_decay, int K, int J,
+			 short pos_accum_max, short neg_accum_max);
+  
+  //! Member functions required by the encoder/decoder
+  //! \brief Rounding function specific to CVSD
+  //! \return the input value rounded to the nearest integer
+  int cvsd_round(double input);
+  
+  //! \brief A power function specific to CVSD data formats
+  //! \return (radix)^power, where radix and power are short integers
+  unsigned int cvsd_pow (short radix, short power);
+ 
+  //! \brief Sums number of 1's in the input
+  //! \return the number of 1s in the four bytes of an input unsigned integer
+  unsigned char cvsd_bitwise_sum (unsigned int input);
+
+  // Members variables related to the CVSD encoder use to update interal reference value
+  short d_min_step;
+  short d_max_step;
+  double d_step_decay;
+  double d_accum_decay;
+
+  int d_K; //!< \brief Size of shift register; the number of output bits remembered in shift register
+  int d_J; //!< \brief Number of bits in the shift register that are equal; size of run of 1s, 0s
+  
+  short d_pos_accum_max;
+  short d_neg_accum_max;
+
+  int d_accum;            //!< \brief Current value of internal reference
+  int d_loop_counter;     //!< \brief Current value of the loop counter
+  unsigned int d_runner;  //!< \brief Current value of the shift register
+  short d_stepsize;       //!< \brief Current value of the step sizer
+
+ public:
+  ~vocoder_cvsd_encode_sb ();	// public destructor
+
+  short min_step() { return d_min_step; }
+  short max_step() { return d_max_step; }
+  double step_decay() { return d_step_decay; }
+  double accum_decay() { return d_accum_decay; }
+  int K() { return d_K; }
+  int J() { return d_J; }
+  short pos_accum_max() { return d_pos_accum_max; }
+  short neg_accum_max() { return d_neg_accum_max; }
+
+  int work (int noutput_items,
+	    gr_vector_const_void_star &input_items,
+	    gr_vector_void_star &output_items);
+};
+
+#endif /* INCLUDED_VOCODER_CVSD_ENCODE_SB_H */
diff --git a/gr-vocoder/lib/Makefile.am b/gr-vocoder/lib/Makefile.am
index 3b3f2c5c1..ec97d96b6 100644
--- a/gr-vocoder/lib/Makefile.am
+++ b/gr-vocoder/lib/Makefile.am
@@ -29,6 +29,8 @@ AM_CPPFLAGS = $(STD_DEFINES_AND_INCLUDES) $(PYTHON_CPPFLAGS) $(WITH_INCLUDES) \
 lib_LTLIBRARIES = libgnuradio-vocoder.la
 
 libgnuradio_vocoder_la_SOURCES = \
+	vocoder_cvsd_encode_sb.cc \
+	vocoder_cvsd_decode_bs.cc \
 	vocoder_gsm_fr_decode_ps.cc \
 	vocoder_gsm_fr_encode_sp.cc
 
diff --git a/gr-vocoder/lib/vocoder_cvsd_decode_bs.cc b/gr-vocoder/lib/vocoder_cvsd_decode_bs.cc
new file mode 100644
index 000000000..baf99f041
--- /dev/null
+++ b/gr-vocoder/lib/vocoder_cvsd_decode_bs.cc
@@ -0,0 +1,193 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2010,2011 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.
+ */
+
+/*
+ * config.h is generated by configure.  It contains the results
+ * of probing for features, options etc.  It should be the first
+ * file included in your .cc file.
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <vocoder_cvsd_decode_bs.h>
+#include <gr_io_signature.h>
+#include <limits.h>
+
+/*
+ * Create a new instance of vocoder_cvsd_decode_bs and return
+ * a boost shared_ptr.  This is effectively the public constructor.
+ */
+vocoder_cvsd_decode_bs_sptr 
+vocoder_make_cvsd_decode_bs (short min_step, short max_step, double step_decay,
+			     double accum_decay,  int K, int J,
+			     short pos_accum_max, short neg_accum_max)
+{
+  return gnuradio::get_initial_sptr(new vocoder_cvsd_decode_bs (min_step, max_step,
+								step_decay, accum_decay, K, J,
+								pos_accum_max, neg_accum_max));
+}
+
+vocoder_cvsd_decode_bs::vocoder_cvsd_decode_bs (short min_step, short max_step, double step_decay, 
+						double accum_decay, int K, int J,
+						short pos_accum_max, short neg_accum_max)
+  : gr_sync_interpolator ("vocoder_cvsd_decode_bs",
+			  gr_make_io_signature (1, 1, sizeof (unsigned char)),
+			  gr_make_io_signature (1, 1, sizeof (short)),
+			  8),
+    d_min_step (min_step), d_max_step(max_step), d_step_decay(step_decay),
+    d_accum_decay(accum_decay), d_K(K), d_J(J), 
+    d_pos_accum_max(pos_accum_max), d_neg_accum_max(neg_accum_max),
+    d_accum(0), 
+    d_loop_counter(1), 
+    d_runner(0),
+    d_runner_mask(0),
+    d_stepsize(min_step)
+  
+{
+  assert(d_K <= 32);
+  assert(d_J <= d_K);
+}
+
+
+vocoder_cvsd_decode_bs::~vocoder_cvsd_decode_bs ()
+{
+  // nothing else required in this example
+}
+
+unsigned char vocoder_cvsd_decode_bs::cvsd_bitwise_sum (unsigned int input)
+{
+  unsigned int temp=input;
+  unsigned char bits=0;
+  
+  while(temp) {
+    temp=temp&(temp-1);
+    bits++;
+  }
+  return bits;
+}
+
+int vocoder_cvsd_decode_bs::cvsd_round (double input)
+{
+  double temp;
+  temp=input+0.5;
+  temp=floor(temp);
+  
+  return (int)temp;
+}
+
+unsigned int vocoder_cvsd_decode_bs::cvsd_pow (short radix, short power)
+{
+  double d_radix = (double) radix;
+  int i_power = (int) power;
+  double output;
+  
+  output=pow(d_radix,i_power);
+  return ( (unsigned int) cvsd_round(output));  
+}
+
+
+int 
+vocoder_cvsd_decode_bs::work (int noutput_items,
+			      gr_vector_const_void_star &input_items,
+			      gr_vector_void_star &output_items)
+{
+ 
+
+  const unsigned char *in = (const unsigned char *) input_items[0];
+  short *out = (short *) output_items[0];
+
+  int i=0;
+  short output_short=0;	         // 2 bytes 0 .. 65,535
+  unsigned char bit_count=0;	 // 1 byte, 0 .. 255
+  unsigned int mask=0;		 // 4 bytes, 0 .. 4,294,967,295
+  unsigned char input_byte=0;	 //  1 bytes
+  unsigned char input_bit=0;	 // 1 byte, 0 .. 255
+  
+  // Loop through each input data point
+  for(i = 0; i < noutput_items/8.0; i++) {
+
+    input_byte = in[i];
+    // Initiliaze bit counter
+    bit_count=0;  	
+    
+    while(bit_count<8) {
+      // Compute the Appropriate Mask
+      mask=cvsd_pow(2,7-bit_count);
+      
+      // Pull off the corresponding bit
+      input_bit = input_byte & mask;
+      
+      // Update the bit counter
+      bit_count++;
+      
+      // Update runner with the next input bit
+      // Runner is a shift-register; shift left, add on newest output bit
+      d_runner = (d_runner<<1) | ((unsigned int) input_bit);
+      
+      // Run this only if you have >= J bits in your shift register
+      if (d_loop_counter>=d_J) {
+	// Update Step Size
+	d_runner_mask=(cvsd_pow(2,d_J)-1);
+	if ((cvsd_bitwise_sum(d_runner & d_runner_mask)>=d_J)||(cvsd_bitwise_sum((~d_runner) & d_runner_mask)>=d_J)) {
+	  // Runs of 1s and 0s
+	  d_stepsize = std::min( (short) (d_stepsize + d_min_step), d_max_step);
+	}
+	else {
+	  // No runs of 1s and 0s
+	  d_stepsize = std::max( (short) cvsd_round(d_stepsize*d_step_decay), d_min_step);
+	}
+      }
+      
+      // Update Accum (i.e. the reference value)
+      if (input_bit) {
+	d_accum=d_accum+d_stepsize;
+      }
+      else {
+	d_accum=d_accum-d_stepsize;
+      }
+      
+      // Multiply by Accum_Decay
+      d_accum=(cvsd_round(d_accum*d_accum_decay));
+      
+      // Check for overflow
+      if (d_accum >=((int) d_pos_accum_max)) {
+	d_accum=(int)d_pos_accum_max;
+      }
+      else if (d_accum <=((int) d_neg_accum_max)) {
+	d_accum=(int)d_neg_accum_max;
+      }
+      
+      // Find the output short to write to the file
+      output_short=((short) d_accum);
+      
+      if (d_loop_counter <= d_K) {
+	d_loop_counter++;
+      }
+      
+      *(out++) = output_short;
+    } // while ()  	
+    
+  } // for()
+  
+  return noutput_items;
+}
diff --git a/gr-vocoder/lib/vocoder_cvsd_encode_sb.cc b/gr-vocoder/lib/vocoder_cvsd_encode_sb.cc
new file mode 100644
index 000000000..71cf6df8c
--- /dev/null
+++ b/gr-vocoder/lib/vocoder_cvsd_encode_sb.cc
@@ -0,0 +1,189 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2010,2011 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.
+ */
+
+/*
+ * config.h is generated by configure.  It contains the results
+ * of probing for features, options etc.  It should be the first
+ * file included in your .cc file.
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <vocoder_cvsd_encode_sb.h>
+#include <gr_io_signature.h>
+#include <limits.h>
+
+/*
+ * Create a new instance of vocoder_cvsd_encode_sb and return
+ * a boost shared_ptr.  This is effectively the public constructor.
+ */
+vocoder_cvsd_encode_sb_sptr 
+vocoder_make_cvsd_encode_sb (short min_step, short max_step, double step_decay,
+			     double accum_decay,  int K, int J,
+			     short pos_accum_max, short neg_accum_max)
+{
+  return gnuradio::get_initial_sptr(new vocoder_cvsd_encode_sb (min_step, max_step,
+								step_decay, accum_decay, K, J,
+								pos_accum_max, neg_accum_max));
+}
+
+vocoder_cvsd_encode_sb::vocoder_cvsd_encode_sb (short min_step, short max_step, double step_decay, 
+						double accum_decay, int K, int J,
+						short pos_accum_max, short neg_accum_max)
+  : gr_sync_decimator ("vocoder_cvsd_encode_sb",
+		       gr_make_io_signature (1, 1, sizeof (short)),
+		       gr_make_io_signature (1, 1, sizeof (unsigned char)),
+		       8),
+    d_min_step (min_step), d_max_step(max_step), d_step_decay(step_decay),
+    d_accum_decay(accum_decay), d_K(K), d_J(J), 
+    d_pos_accum_max(pos_accum_max), d_neg_accum_max(neg_accum_max),
+    d_accum(0), 
+    d_loop_counter(1), 
+    d_runner(0),
+    d_stepsize(min_step)
+
+{
+  assert(d_K <= 32);
+  assert(d_J <= d_K);
+}
+
+
+vocoder_cvsd_encode_sb::~vocoder_cvsd_encode_sb ()
+{
+  // nothing else required in this example
+}
+
+unsigned char vocoder_cvsd_encode_sb::cvsd_bitwise_sum (unsigned int input)
+{
+  unsigned int temp=input;
+  unsigned char bits=0;
+  
+  while(temp) {
+    temp=temp&(temp-1);
+    bits++;
+  }
+  return bits;
+}
+
+int vocoder_cvsd_encode_sb::cvsd_round (double input)
+{
+  double temp;
+  temp=input+0.5;
+  temp=floor(temp);
+  
+  return (int)temp;
+}
+
+unsigned int vocoder_cvsd_encode_sb::cvsd_pow (short radix, short power)
+{
+  double d_radix = (double) radix;
+  int i_power = (int) power;
+  double output;
+
+  output=pow(d_radix,i_power);
+  return ( (unsigned int) cvsd_round(output));  
+}
+
+int 
+vocoder_cvsd_encode_sb::work (int noutput_items,
+			      gr_vector_const_void_star &input_items,
+			      gr_vector_void_star &output_items)
+{
+  const short *in = (const short *) input_items[0];
+  unsigned char *out = (unsigned char *) output_items[0];
+
+  unsigned short i=0;		 // 2 bytes, 0 .. 65,535
+  unsigned char output_bit=0;	 // 1 byte, 0 .. 255
+  unsigned char output_byte=0;	 // 1 bytes 0.255
+  unsigned char bit_count=0;		 // 1 byte, 0 .. 255
+  unsigned int mask=0;		 // 4 bytes, 0 .. 4,294,967,295
+  
+  // Loop through each input data point
+  for(i = 0; i < noutput_items*8; i++) {
+    if((int)in[i] >= d_accum) {    // Note:  sign((data(n)-accum))
+      output_bit=1;
+    }
+    else {
+      output_bit=0;
+    }
+    
+    // Update Accum (i.e. the reference value)
+    if (output_bit) {
+      d_accum=d_accum+d_stepsize;
+      //printf("Addding %d to the accum; the result is: %d.\n", d_stepsize, d_accum);
+    }
+    else {
+      d_accum=d_accum-d_stepsize;
+      //printf("Subtracting %d to the accum; the result is: %d.\n", d_stepsize, d_accum);
+    }
+
+    // Multiply by Accum_Decay
+    d_accum=(cvsd_round(d_accum*d_accum_decay));
+
+    // Check for overflow
+    if (d_accum >= ((int)d_pos_accum_max)) {
+      d_accum = (int)d_pos_accum_max;
+    }
+    else if(d_accum <= ((int) d_neg_accum_max)) {
+      d_accum = (int) d_neg_accum_max;
+    }
+		 
+    // Update runner with the last output bit
+    // Update Step Size
+    if (d_loop_counter >= d_J) { // Run this only if you have >= J bits in your shift register
+      mask=(cvsd_pow(2, d_J) - 1);
+      if ((cvsd_bitwise_sum(d_runner & mask) >= d_J) || (cvsd_bitwise_sum((~d_runner) & mask) >= d_J)) {
+	// Runs of 1s and 0s
+	d_stepsize = std::min( (short)(d_stepsize + d_min_step), d_max_step);
+      }
+      else {
+	// No runs of 1s and 0s
+	d_stepsize = std::max( (short)cvsd_round(d_stepsize*d_step_decay), d_min_step);     
+      }
+    }
+	     
+    // Runner is a shift-register; shift left, add on newest output bit
+    d_runner = (d_runner<<1) | ((unsigned int) output_bit);
+
+    // Update the ouput type; shift left, add on newest output bit
+    // If you have put in 8 bits, output it as a byte
+    output_byte = (output_byte<<1) | output_bit;
+    bit_count++;
+    
+    if (d_loop_counter <= d_K) {
+      d_loop_counter++;
+    }
+
+    // If you have put 8 bits, output and clear.
+    if (bit_count==8) {
+      // Read in short from the file
+      *(out++) = output_byte;
+      
+      // Reset the bit_count
+      bit_count=0;
+      output_byte=0;
+    }
+  } // While
+
+  return noutput_items;
+}
diff --git a/gr-vocoder/python/Makefile.am b/gr-vocoder/python/Makefile.am
index b71a47618..e4dc1ac61 100644
--- a/gr-vocoder/python/Makefile.am
+++ b/gr-vocoder/python/Makefile.am
@@ -26,9 +26,11 @@ vocoderdir = $(grpythondir)/vocoder
 TESTS = run_tests
 
 noinst_PYTHON = \
-	qa_gsm_full_rate.py		
+	qa_gsm_full_rate.py \
+	qa_cvsd_vocoder.py
 
 vocoder_PYTHON = \
-	__init__.py
+	__init__.py \
+	cvsd.py
 
 EXTRA_DIST += run_tests.in
diff --git a/gr-vocoder/python/__init__.py b/gr-vocoder/python/__init__.py
index 65185eb34..eb5fa6fc1 100644
--- a/gr-vocoder/python/__init__.py
+++ b/gr-vocoder/python/__init__.py
@@ -20,3 +20,4 @@
 # 
 
 from vocoder_swig import *
+from cvsd import *
diff --git a/gr-vocoder/python/cvsd.py b/gr-vocoder/python/cvsd.py
new file mode 100644
index 000000000..27b06ddeb
--- /dev/null
+++ b/gr-vocoder/python/cvsd.py
@@ -0,0 +1,86 @@
+#!/usr/bin/env python
+#
+# Copyright 2007,2011 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.
+# 
+
+from gnuradio import gr
+import vocoder_swig
+
+class cvsd_encode_fb(gr.hier_block2):
+    '''
+    This is a wrapper for the CVSD encoder that performs interpolation and filtering
+    necessary to work with the vocoding. It converts an incoming float (+-1) to a short, scales
+    it (to 32000; slightly below the maximum value), interpolates it, and then vocodes it.
+
+    The incoming sampling rate can be anything, though, of course, the higher the sampling rate and the
+    higher the interpolation rate are, the better the sound quality.
+    '''
+    
+    def __init__(self, resample=8, bw=0.5):
+        '''
+        When using the CVSD vocoder, appropriate sampling rates are from 8k to 64k with resampling rates
+        from 1 to 8. A rate of 8k with a resampling rate of 8 provides a good quality signal.
+        '''
+
+	gr.hier_block2.__init__(self, "cvsd_encode",
+				gr.io_signature(1, 1, gr.sizeof_float), # Input signature
+				gr.io_signature(1, 1, gr.sizeof_char))  # Output signature
+
+        scale_factor = 32000.0
+        self.interp = resample
+
+        src_scale = gr.multiply_const_ff(scale_factor)
+        taps = gr.firdes.low_pass(self.interp, self.interp, bw, 2*bw)
+        interp = gr.interp_fir_filter_fff(self.interp, taps)
+        f2s = gr.float_to_short()
+        enc = vocoder_swig.cvsd_encode_sb()
+
+        self.connect(self, src_scale, interp, f2s, enc, self)
+
+
+class cvsd_decode_bf(gr.hier_block2):
+    '''
+    This is a wrapper for the CVSD decoder that performs decimation and filtering
+    necessary to work with the vocoding. It converts an incoming CVSD-encoded short to a float, decodes it
+    to a float, decimates it, and scales it (by 32000; slightly below the maximum value to avoid clipping).
+
+    The sampling rate can be anything, though, of course, the higher the sampling rate and the
+    higher the interpolation rate are, the better the sound quality.
+    '''
+
+    def __init__(self, resample=8, bw=0.5):
+        '''
+        When using the CVSD vocoder, appropriate sampling rates are from 8k to 64k with resampling rates
+        from 1 to 8. A rate of 8k with a resampling rate of 8 provides a good quality signal.
+        '''
+	gr.hier_block2.__init__(self, "cvsd_decode",
+				gr.io_signature(1, 1, gr.sizeof_char),  # Input signature
+				gr.io_signature(1, 1, gr.sizeof_float)) # Output signature
+
+        scale_factor = 32000.0
+        self.decim = resample
+
+        dec = vocoder_swig.cvsd_decode_bs()
+        s2f = gr.short_to_float()
+        taps = gr.firdes.low_pass(1, 1, bw, 2*bw)
+        decim = gr.fir_filter_fff(self.decim, taps)
+        sink_scale = gr.multiply_const_ff(1.0/scale_factor)
+
+        self.connect(self, dec, s2f, decim, sink_scale, self)
diff --git a/gr-vocoder/python/qa_cvsd_vocoder.py b/gr-vocoder/python/qa_cvsd_vocoder.py
new file mode 100755
index 000000000..53045e4a9
--- /dev/null
+++ b/gr-vocoder/python/qa_cvsd_vocoder.py
@@ -0,0 +1,123 @@
+#!/usr/bin/env python
+#
+# Copyright 2007,2010,2011 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.
+# 
+
+from gnuradio import gr, gr_unittest
+from vocoder_swig import *
+from cvsd import *
+
+class test_cvsd_vocoder (gr_unittest.TestCase):
+
+    def setUp (self):
+        self.tb = gr.top_block()
+        
+    def tearDown (self):
+        self.tb = None
+
+    def test001_module_load (self):
+        raw_enc = cvsd_encode_sb();
+        raw_dec = cvsd_decode_bs();
+        hb_enc = cvsd_encode_fb();
+        hb_dec = cvsd_decode_bf();
+
+
+    """ Disable for now
+    def test01(self):
+        sample_rate = 8000
+        scale_factor = 32000
+
+        expected_data = (6.9670547250243192e-21, -2.4088578356895596e-05,
+                         -5.1261918997624889e-05, 7.2410854045301676e-05,
+                         8.444241393590346e-05, -1.2537107068055775e-05,
+                         0.00024186755763366818, -0.00060463894624263048,
+                         0.00064864184241741896, 0.010409165173768997,
+                         0.0087582804262638092, 0.017965050414204597,
+                         0.010722399689257145, 0.006602009292691946,
+                         0.02213001623749733, 0.0079685859382152557,
+                         0.033707316964864731, 0.027021972462534904,
+                         0.0086071854457259178, 0.0081678871065378189,
+                         0.039343506097793579, 0.030671956017613411,
+                         0.029626710340380669, 0.020126519724726677,
+                         0.023636780679225922, 0.0064640454947948456,
+                         -0.0038861562497913837, 0.0021134600974619389,
+                         -0.0088051930069923401, -0.00023228264763019979,
+                         -0.033737499266862869, -0.033141419291496277,
+                         -0.037145044654607773, -0.0080892946571111679,
+                         -0.077117636799812317, -0.078382067382335663,
+                         -0.055503919720649719, -0.019355267286300659,
+                         -0.022441385313868523, -0.073706060647964478,
+                         -0.054677654057741165, -0.047119375318288803,
+                         -0.044418536126613617, -0.036084383726119995,
+                         -0.0206278245896101, -0.031200021505355835,
+                         -0.0004070434661116451, 0.0006594572332687676,
+                         -0.016584658995270729, 0.07387717068195343,
+                         -0.0063191778026521206, 0.051200628280639648,
+                         -0.029480356723070145, 0.05176771804690361,
+                         0.038578659296035767, 0.026550088077783585,
+                         0.067103870213031769, 0.001888439292088151,
+                         0.28141644597053528, 0.49543789029121399,
+                         0.6626054048538208, 0.79180729389190674,
+                         0.89210402965545654, 0.96999943256378174,
+                         1.0261462926864624, 1.0267977714538574,
+                         1.0251555442810059, 1.0265737771987915,
+                         1.0278496742248535, 1.0208886861801147,
+                         1.0325057506561279, 0.91415292024612427,
+                         0.83941859006881714, 0.67373806238174438,
+                         0.51683622598648071, 0.38949671387672424,
+                         0.16016888618469238, 0.049505095928907394,
+                         -0.16699212789535522, -0.26886492967605591,
+                         -0.49256673455238342, -0.59178370237350464,
+                         -0.73317724466323853, -0.78922677040100098,
+                         -0.88782668113708496, -0.96708977222442627,
+                         -0.96490746736526489, -0.94962418079376221,
+                         -0.94716215133666992, -0.93755108118057251,
+                         -0.84852480888366699, -0.80485564470291138,
+                         -0.69762390851974487, -0.58398681879043579,
+                         -0.45891636610031128, -0.29681697487831116,
+                         -0.16035343706607819, 0.014823081903159618,
+                         0.16282452642917633, 0.33802291750907898)
+
+        src = gr.sig_source_f(sample_rate, gr.GR_SIN_WAVE, 200, 1, 0)
+        head = gr.head(gr.sizeof_float, 100)
+        src_scale = gr.multiply_const_ff(scale_factor)
+        
+        interp = blks2.rational_resampler_fff(8, 1)
+        f2s = gr.float_to_short ()
+        
+        enc = cvsd_vocoder.encode_sb()
+        dec = cvsd_vocoder.decode_bs()
+        
+        s2f = gr.short_to_float ()
+        decim = blks2.rational_resampler_fff(1, 8)
+        
+        sink_scale = gr.multiply_const_ff(1.0/scale_factor)
+        sink = gr.vector_sink_f()
+        
+        self.tb.connect(src, src_scale, interp, f2s, enc)
+        self.tb.connect(enc, dec, s2f, decim, sink_scale, head, sink)
+        self.tb.run()
+	print sink.data()
+	
+        self.assertFloatTuplesAlmostEqual (expected_data, sink.data(), 5)
+    """
+    
+if __name__ == '__main__':
+    gr_unittest.run(test_cvsd_vocoder, "test_cvsd_vocoder.xml")
diff --git a/gr-vocoder/python/qa_gsm_full_rate.py b/gr-vocoder/python/qa_gsm_full_rate.py
index 4164a1965..f9125905c 100755
--- a/gr-vocoder/python/qa_gsm_full_rate.py
+++ b/gr-vocoder/python/qa_gsm_full_rate.py
@@ -21,7 +21,7 @@
 # 
 
 from gnuradio import gr, gr_unittest
-import gsm_full_rate
+import vocoder_swig
 
 class test_gsm_vocoder (gr_unittest.TestCase):
 
@@ -31,5 +31,9 @@ class test_gsm_vocoder (gr_unittest.TestCase):
     def tearDown (self):
         self.tb = None
 
+    def test001_module_load (self):
+        enc = vocoder_swig.gsm_fr_encode_sp();
+        dec = vocoder_swig.gsm_fr_decode_ps();
+
 if __name__ == '__main__':
     gr_unittest.run(test_gsm_vocoder, "test_gsm_vocoder.xml")
diff --git a/gr-vocoder/python/run_tests.in b/gr-vocoder/python/run_tests.in
index 96eefc559..e0c61a6b4 100644
--- a/gr-vocoder/python/run_tests.in
+++ b/gr-vocoder/python/run_tests.in
@@ -5,6 +5,6 @@
 # 3rd parameter is path to Python QA directory
 
 @top_builddir@/run_tests.sh \
-    @abs_top_srcdir@/gr-gsm-fr-vocoder \
-    @abs_top_builddir@/gr-gsm-fr-vocoder \
+    @abs_top_srcdir@/gr-vocoder \
+    @abs_top_builddir@/gr-vocoder \
     @srcdir@
diff --git a/gr-vocoder/swig/Makefile.am b/gr-vocoder/swig/Makefile.am
index 54c1e004d..202032c19 100644
--- a/gr-vocoder/swig/Makefile.am
+++ b/gr-vocoder/swig/Makefile.am
@@ -57,6 +57,8 @@ vocoder_swig_la_swig_libadd = \
 
 # additional SWIG files to be installed
 vocoder_swig_swiginclude_headers = \
+	vocoder_cvsd_decode_bs.i \
+	vocoder_cvsd_encode_sb.i \
 	vocoder_gsm_fr_encode_sp.i \
 	vocoder_gsm_fr_decode_ps.i
 
diff --git a/gr-vocoder/swig/vocoder_cvsd_decode_bs.i b/gr-vocoder/swig/vocoder_cvsd_decode_bs.i
new file mode 100644
index 000000000..e990f5440
--- /dev/null
+++ b/gr-vocoder/swig/vocoder_cvsd_decode_bs.i
@@ -0,0 +1,44 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2009,2011 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.
+ */
+
+%{
+#include "vocoder_cvsd_decode_bs.h"
+%}
+
+GR_SWIG_BLOCK_MAGIC(vocoder,cvsd_decode_bs);
+
+vocoder_cvsd_decode_bs_sptr vocoder_make_cvsd_decode_bs (short min_step=10,
+							 short max_step=1280,
+							 double step_decay=0.9990234375,
+							 double accum_decay= 0.96875,
+							 int K=32,
+							 int J=4,
+							 short pos_accum_max=32767,
+							 short neg_accum_max=-32767);
+
+class vocoder_cvsd_decode_bs : public gr_sync_interpolator
+{
+private:
+  vocoder_cvsd_decode_bs (short min_step, short max_step, double step_decay,
+			  double accum_decay, int K, int J,
+			  short pos_accum_max, short neg_accum_max);
+};
diff --git a/gr-vocoder/swig/vocoder_cvsd_encode_sb.i b/gr-vocoder/swig/vocoder_cvsd_encode_sb.i
new file mode 100644
index 000000000..5db7b3a48
--- /dev/null
+++ b/gr-vocoder/swig/vocoder_cvsd_encode_sb.i
@@ -0,0 +1,44 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2007,2009,2011 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.
+ */
+
+%{
+#include "vocoder_cvsd_encode_sb.h"
+%}
+
+GR_SWIG_BLOCK_MAGIC(vocoder,cvsd_encode_sb);
+
+vocoder_cvsd_encode_sb_sptr vocoder_make_cvsd_encode_sb (short min_step=10,
+							 short max_step=1280,
+							 double step_decay=0.9990234375,
+							 double accum_decay= 0.96875,
+							 int K=32,
+							 int J=4,
+							 short pos_accum_max=32767,
+							 short neg_accum_max=-32767);
+
+class vocoder_cvsd_encode_sb : public gr_sync_decimator
+{
+private:
+  vocoder_cvsd_encode_sb (short min_step, short max_step, double step_decay,
+			  double accum_decay, int K, int J,
+			  short pos_accum_max, short neg_accum_max);
+};
diff --git a/gr-vocoder/swig/vocoder_swig.i b/gr-vocoder/swig/vocoder_swig.i
index 7876366f7..19798ec79 100644
--- a/gr-vocoder/swig/vocoder_swig.i
+++ b/gr-vocoder/swig/vocoder_swig.i
@@ -22,6 +22,8 @@
 
 %include "gnuradio.i"
 
+%include "vocoder_cvsd_decode_bs.i"
+%include "vocoder_cvsd_encode_sb.i"
 %include "vocoder_gsm_fr_encode_sp.i"
 %include "vocoder_gsm_fr_decode_ps.i"