7 files changed, 785 insertions, 0 deletions
diff --git a/gr-cvsd-vocoder/src/lib/Makefile.am b/gr-cvsd-vocoder/src/lib/Makefile.am
new file mode 100644
index 0000000000..644966b852
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/Makefile.am
@@ -0,0 +1,97 @@
+#
+# Copyright 2004,2005 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 2, 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 $(top_srcdir)/Makefile.common
+
+# Install this stuff so that it ends up as the gnuradio.vocoder module
+# This usually ends up at:
+#   ${prefix}/lib/python${python_version}/site-packages/gnuradio/vocoder
+
+ourpythondir = $(grpythondir)/vocoder
+ourlibdir    = $(grpyexecdir)/vocoder
+
+INCLUDES = $(STD_DEFINES_AND_INCLUDES) $(PYTHON_CPPFLAGS)
+
+SWIGPYTHONARGS = $(SWIGPYTHONFLAGS) $(STD_DEFINES_AND_INCLUDES)
+
+
+ALL_IFILES = 				\
+	$(LOCAL_IFILES)			\
+	$(NON_LOCAL_IFILES)		
+
+NON_LOCAL_IFILES =			\
+	$(GNURADIO_I)
+
+
+LOCAL_IFILES = 				\
+	$(top_srcdir)/gr-cvsd-vocoder/src/lib/cvsd_vocoder.i
+
+# These files are built by SWIG.  The first is the C++ glue.
+# The second is the python wrapper that loads the _howto shared library
+# and knows how to call our extensions.
+
+BUILT_SOURCES = 			\
+	cvsd_vocoder.cc		\
+	cvsd_vocoder.py				
+
+# This gets cvsd_vocoder.py installed in the right place
+ourpython_PYTHON =			\
+	__init__.py			\
+	cvsd_vocoder.py
+
+ourlib_LTLIBRARIES = _cvsd_vocoder.la
+
+# These are the source files that go into the shared library
+_cvsd_vocoder_la_SOURCES = 		\
+	cvsd_decode_bs.cc		\
+	cvsd_encode_sb.cc		\
+	cvsd_vocoder.cc		
+
+
+# magic flags
+_cvsd_vocoder_la_LDFLAGS = $(NO_UNDEFINED) -module -avoid-version
+
+# link the library against the c++ standard library
+_cvsd_vocoder_la_LIBADD = 	\
+	$(PYTHON_LDFLAGS)	\
+	$(GNURADIO_CORE_LA)	\
+	-lstdc++			
+
+cvsd_vocoder.cc cvsd_vocoder.py: cvsd_vocoder.i $(ALL_IFILES)
+	$(SWIG) $(SWIGPYTHONARGS) -module cvsd_vocoder -o cvsd_vocoder.cc $(LOCAL_IFILES)
+
+# These headers get installed in ${prefix}/include/gnuradio
+grinclude_HEADERS =			\
+	cvsd_decode_bs.h		\
+	cvsd_encode_sb.h		
+
+# These swig headers get installed in ${prefix}/include/gnuradio/swig
+swiginclude_HEADERS = 			\
+	$(LOCAL_IFILES)
+
+
+MOSTLYCLEANFILES = $(BUILT_SOURCES) *.pyc
+
+# Don't distribute output of swig
+dist-hook:
+	@for file in $(BUILT_SOURCES); do echo $(RM) $(distdir)/$$file; done
+	@for file in $(BUILT_SOURCES); do $(RM) $(distdir)/$$file; done
+
diff --git a/gr-cvsd-vocoder/src/lib/__init__.py b/gr-cvsd-vocoder/src/lib/__init__.py
new file mode 100644
index 0000000000..4f066df09b
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/__init__.py
@@ -0,0 +1,20 @@
+#
+# Copyright 2005 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 2, 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.
+# 
diff --git a/gr-cvsd-vocoder/src/lib/cvsd_decode_bs.cc b/gr-cvsd-vocoder/src/lib/cvsd_decode_bs.cc
new file mode 100644
index 0000000000..def2d946e3
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/cvsd_decode_bs.cc
@@ -0,0 +1,196 @@
+/* -*- 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 2, 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 <cvsd_decode_bs.h>
+#include <gr_io_signature.h>
+
+/*
+ * Create a new instance of cvsd_decode_bs and return
+ * a boost shared_ptr.  This is effectively the public constructor.
+ */
+cvsd_decode_bs_sptr 
+cvsd_make_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 cvsd_decode_bs_sptr (new cvsd_decode_bs (min_step, max_step,
+						  step_decay, accum_decay, K, J,
+						  pos_accum_max, neg_accum_max));
+}
+
+cvsd_decode_bs::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 ("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_pos_accum_max <= SHRT_MAX);
+  assert(d_neg_accum_max >= -SHRT_MAX);
+  assert(d_K <= 32);
+  assert(d_J <= d_K);
+  
+  // nothing else required in this example
+}
+
+
+cvsd_decode_bs::~cvsd_decode_bs ()
+{
+  // nothing else required in this example
+}
+
+unsigned char 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 cvsd_decode_bs::cvsd_round (double input)
+{
+  double temp;
+  temp=input+0.5;
+  temp=floor(temp);
+  
+  return (int)temp;
+}
+
+unsigned int 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 
+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-cvsd-vocoder/src/lib/cvsd_decode_bs.h b/gr-cvsd-vocoder/src/lib/cvsd_decode_bs.h
new file mode 100644
index 0000000000..d23c20e30a
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/cvsd_decode_bs.h
@@ -0,0 +1,97 @@
+/* -*- 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 2, 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_CVSD_DECODE_BS_H
+#define INCLUDED_CVSD_DECODE_BS_H
+
+#include <gr_sync_interpolator.h>
+
+class cvsd_decode_bs;
+
+typedef boost::shared_ptr<cvsd_decode_bs> cvsd_decode_bs_sptr;
+
+cvsd_decode_bs_sptr cvsd_make_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 cvsd_decode_bs : public gr_sync_interpolator
+{
+private:
+  friend cvsd_decode_bs_sptr cvsd_make_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);
+
+  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);
+
+  int cvsd_round(double input);
+  unsigned int cvsd_pow (short radix, short power);
+  unsigned char cvsd_bitwise_sum (unsigned int input);
+
+  short d_min_step;
+  short d_max_step;
+  double d_step_decay;
+  double d_accum_decay;
+
+  //! \brief Size of shift register; the number of output bits remembered in shift register
+  int d_K;
+
+  //! \brief Number of bits in the shift register that are equal; size of run of 1s, 0s
+  int d_J;
+
+  short d_pos_accum_max;
+  short d_neg_accum_max;
+
+  int d_accum;
+  int d_loop_counter;
+  unsigned int d_runner;
+  unsigned int d_runner_mask;	 // 4 bytes, 0 .. 4,294,967,295
+  short d_stepsize;
+
+ public:
+  ~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_CVSD_DECODE_BS_H */
diff --git a/gr-cvsd-vocoder/src/lib/cvsd_encode_sb.cc b/gr-cvsd-vocoder/src/lib/cvsd_encode_sb.cc
new file mode 100644
index 0000000000..37e2fb0b47
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/cvsd_encode_sb.cc
@@ -0,0 +1,194 @@
+/* -*- 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 2, 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 <cvsd_encode_sb.h>
+#include <gr_io_signature.h>
+
+/*
+ * Create a new instance of cvsd_encode_sb and return
+ * a boost shared_ptr.  This is effectively the public constructor.
+ */
+cvsd_encode_sb_sptr 
+cvsd_make_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 cvsd_encode_sb_sptr (new cvsd_encode_sb (min_step, max_step,
+						  step_decay, accum_decay, K, J,
+						  pos_accum_max, neg_accum_max));
+}
+
+cvsd_encode_sb::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 ("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_pos_accum_max <= SHRT_MAX);
+  assert(d_neg_accum_max >= -SHRT_MAX);
+  assert(d_K <= 32);
+  assert(d_J <= d_K);
+
+  // nothing else required in this example
+}
+
+
+cvsd_encode_sb::~cvsd_encode_sb ()
+{
+  // nothing else required in this example
+}
+
+unsigned char 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 cvsd_encode_sb::cvsd_round (double input)
+{
+  double temp;
+  temp=input+0.5;
+  temp=floor(temp);
+  
+  return (int)temp;
+}
+
+unsigned int 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 
+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-cvsd-vocoder/src/lib/cvsd_encode_sb.h b/gr-cvsd-vocoder/src/lib/cvsd_encode_sb.h
new file mode 100644
index 0000000000..57734ca15a
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/cvsd_encode_sb.h
@@ -0,0 +1,96 @@
+/* -*- 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 2, 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_CVSD_ENCODER_SB_H
+#define INCLUDED_CVSD_ENCODER_SB_H
+
+#include <gr_sync_decimator.h>
+
+class cvsd_encode_sb;
+
+typedef boost::shared_ptr<cvsd_encode_sb> cvsd_encode_sb_sptr;
+
+cvsd_encode_sb_sptr cvsd_make_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 cvsd_encode_sb : public gr_sync_decimator
+{
+private:
+  friend cvsd_encode_sb_sptr cvsd_make_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);
+
+  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);
+  
+  int cvsd_round(double input);
+  unsigned int cvsd_pow (short radix, short power);
+  unsigned char cvsd_bitwise_sum (unsigned int input);
+
+  short d_min_step;
+  short d_max_step;
+  double d_step_decay;
+  double d_accum_decay;
+
+  //! \brief Size of shift register; the number of output bits remembered in shift register
+  int d_K;
+
+  //! \brief Number of bits in the shift register that are equal; size of run of 1s, 0s
+  int d_J;
+
+  short d_pos_accum_max;
+  short d_neg_accum_max;
+
+  int d_accum;
+  int d_loop_counter;
+  unsigned int d_runner;
+  short d_stepsize;
+
+ public:
+  ~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_CVSD_ENCODE_SB_H */
diff --git a/gr-cvsd-vocoder/src/lib/cvsd_vocoder.i b/gr-cvsd-vocoder/src/lib/cvsd_vocoder.i
new file mode 100644
index 0000000000..5e618187fc
--- /dev/null
+++ b/gr-cvsd-vocoder/src/lib/cvsd_vocoder.i
@@ -0,0 +1,85 @@
+/* -*- 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 2, 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.
+ */
+
+%feature("autodoc","1");
+%include "exception.i"
+%import "gnuradio.i"
+
+%{
+#include "gnuradio_swig_bug_workaround.h"	// mandatory bug fix
+#include "cvsd_encode_sb.h"
+#include "cvsd_decode_bs.h"
+#include <stdexcept>
+%}
+
+GR_SWIG_BLOCK_MAGIC(cvsd,encode_sb);
+
+cvsd_encode_sb_sptr cvsd_make_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 cvsd_encode_sb : public gr_sync_decimator
+{
+private:
+  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);
+  
+
+ public:
+  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; }
+};
+
+// ----------------------------------------------------------------
+
+GR_SWIG_BLOCK_MAGIC(cvsd,decode_bs);
+
+cvsd_decode_bs_sptr cvsd_make_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 cvsd_decode_bs : public gr_sync_interpolator
+{
+private:
+  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);
+  
+ public:
+};