I believe the code you mentioned is in there. just in case, here is my repeater_vocoder.cc:


/* -*- c++ -*- */
/*
 * GNU Radio interface for Pavel Yazev's Project 25 IMBE Encoder/Decoder
 *
 * Copyright 2004 Free Software Foundation, Inc.
 * Copyright 2009 Pavel Yazev E-mail: pyazev@gmail.com
 * Copyright 2009-2013 KA1RBI
 *
 * This 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.
 *
 * It 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 it; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, 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 <vector>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include <imbe_vocoder.h>
#include <repeater_vocoder.h>
#include <op25_p25_frame.h>
#include <op25_imbe_frame.h>
#include <gr_io_signature.h>

/* bits to be preset to 1 for all transmitted frames */
static const bool ldu1_preset[] = {
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 0-35 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 36-71 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 72-107 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 108-143 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 144-179 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 180-215 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 216-251 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 252-287 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 288-323 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 324-359 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 360-395 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 396-431 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 432-467 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 468-503 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 504-539 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 540-575 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 576-611 */
  0,1,0,1,1,0,1,1,0,1,0,1,0,1,0,1,1,0,0,1,0,1,0,1,0,1,1,0,0,0,0,0,0,0,1,0, /* 612-647 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 648-683 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 684-719 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 720-755 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0, /* 756-791 */
  1,0,1,0,0,1,1,0,1,0,1,0,1,0,0,1,1,0,1,0,1,0,1,0,0,1,1,0,1,0,1,0,1,0,0,1, /* 792-827 */
  1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 828-863 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 864-899 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 900-935 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 936-971 */
  0,0,0,0,0,0,1,0,1,1,1,0,0,0,0,1,1,1,1,1,0,0,1,1,1,1,1,0,0,1,0,1,0,1,1,0, /* 972-1007 */
  0,1,0,0,1,0,0,1,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1008-1043 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1044-1079 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1080-1115 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1116-1151 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,1,1,1,1,0,1,1, /* 1152-1187 */
  1,1,1,1,0,0,1,1,1,1,0,0,0,0,1,0,0,0,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1188-1223 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1224-1259 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1260-1295 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1296-1331 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,1,0,0,0,0,1,1, /* 1332-1367 */
  1,1,1,0,1,1,0,1,1,1,0,0,1,0,1,1,0,1,0,0,0,1,1,0,1,1,1,0,0,1,0,0,0,0,0,0, /* 1368-1403 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1404-1439 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1440-1475 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1476-1511 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1512-1547 */
  1,0,1,0,1,0,0,1,0,0,0,0,1,0,1,0,1,0,1,0,1,0,0,1,0,0,0,0,1,0,0,0,0,0,1,0, /* 1548-1583 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1584-1619 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1620-1655 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1656-1691 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0  /* 1692-1727 */
};

static const bool ldu2_preset[] = {
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 0-35 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 36-71 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 72-107 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 108-143 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 144-179 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 180-215 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 216-251 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 252-287 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 288-323 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 324-359 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 360-395 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 396-431 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 432-467 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 468-503 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 504-539 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 540-575 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 576-611 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 612-647 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 648-683 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 684-719 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 720-755 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 756-791 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 792-827 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 828-863 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 864-899 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,1, /* 900-935 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 936-971 */
  0,0,0,0,0,0,1,0,0,0,0,0,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 972-1007 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1008-1043 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1044-1079 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1080-1115 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1116-1151 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,1,1,1,0,1,0,0,0,1,0,1,1,0,1,0,0, /* 1152-1187 */
  1,0,0,0,1,0,1,1,0,1,1,0,0,1,0,0,1,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1188-1223 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1224-1259 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1260-1295 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1296-1331 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,1,1,0,1,0,1,0,1,1, /* 1332-1367 */
  1,1,1,1,0,1,0,0,1,1,1,1,0,0,0,1,1,1,1,1,1,1,0,1,0,1,1,0,0,0,0,0,0,0,0,0, /* 1368-1403 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1404-1439 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1440-1475 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1476-1511 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1512-1547 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1548-1583 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1584-1619 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1620-1655 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 1656-1691 */
  0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0, /* 1692-1727 */
};

static void clear_bits(bit_vector& v) {
    for (size_t i=0; i<v.size(); i++) {
        v[i]=0;
    }
}

/*
 * Create a new instance of repeater_vocoder and return
 * a boost shared_ptr.  This is effectively the public constructor.
 */
repeater_vocoder_sptr
repeater_make_vocoder (bool encode_flag, bool verbose_flag, int stretch_amt, char* udp_host, int udp_port, bool raw_vectors_flag)
{
  return repeater_vocoder_sptr (new repeater_vocoder (encode_flag, verbose_flag, stretch_amt, udp_host, udp_port, raw_vectors_flag));
}

//////////////////////////////////////////////////////////////
//    enc/dec        udp    operation
//    dec        no    byte input; short output
//    dec        yes    byte input; null output
//    enc        no    short input; char output
//    enc        yes    short input; null output

#define M_IN(encode_flag, udp_port)  (1)
#define M_OUT(encode_flag, udp_port) ((udp_port) ? 0 : 1)
#define S_IN(encode_flag, udp_port)  ((encode_flag) ? sizeof(int16_t) : sizeof(uint8_t))
#define S_OUT(encode_flag, udp_port) ((udp_port) ? 0 : ((encode_flag) ? sizeof(uint8_t) : sizeof(int16_t)))

/*
 * The private constructor
 */
repeater_vocoder::repeater_vocoder (bool encode_flag, bool verbose_flag, int stretch_amt, char* udp_host, int udp_port, bool raw_vectors_flag)
    : gr_block ("vocoder",
          gr_make_io_signature (M_IN(encode_flag, udp_port), M_IN(encode_flag, udp_port), S_IN(encode_flag, udp_port)),
          gr_make_io_signature (M_OUT(encode_flag, udp_port), M_OUT(encode_flag, udp_port), S_OUT(encode_flag, udp_port))),
    frame_cnt(0),
    write_sock(0),
    write_bufp(0),
    peak_amplitude(0),
    peak(0),
    samp_ct(0),
    rxbufp(0),
    codeword_ct(0),
    sampbuf_ct(0),
    stretch_count(0),
    save_l(0),
    f_body(P25_VOICE_FRAME_SIZE)
{
    opt_encode_flag = encode_flag;
    opt_dump_raw_vectors = raw_vectors_flag;
    opt_verbose = verbose_flag;
    opt_udp_port = udp_port;

    opt_stretch_amt = 0;
    if (stretch_amt < 0) {
        opt_stretch_sign = -1;
        opt_stretch_amt = 0 - stretch_amt;
    } else {
        opt_stretch_sign = 1;
        opt_stretch_amt = stretch_amt;
    }

    if (opt_udp_port == 0)
        if (encode_flag) {
            // local output to gr source
            // encoding: an LDU's worth of dibits
            set_output_multiple(P25_VOICE_FRAME_SIZE >> 1);
        } else {
            // decoding: an LDU's worth of audio samples
            // set_output_multiple(FRAME * nof_voice_codewords);
        }
    else
        // remote UDP output
        init_sock(udp_host, opt_udp_port);

    clear_bits(f_body);

    const char *p = getenv("IMBE");
    if (p && strcasecmp(p, "soft") == 0)
        d_software_imbe_decoder = true;
    else
        d_software_imbe_decoder = false;
}

/*
 * Our virtual destructor.
 */
repeater_vocoder::~repeater_vocoder ()
{
}

static const int STATS_INTERVAL = 20;
static const int SAMP_INTERVAL = 8192;

void repeater_vocoder::append_imbe_codeword(bit_vector& frame_body, int16_t frame_vector[], unsigned int& codeword_ct)
{
    voice_codeword cw(voice_codeword_sz);
    uint8_t obuf[P25_VOICE_FRAME_SIZE/2];
    // construct 144-bit codeword from 88 bits of parameters
    imbe_header_encode(cw, frame_vector[0], frame_vector[1], frame_vector[2], frame_vector[3], frame_vector[4], frame_vector[5], frame_vector[6], frame_vector[7]);

    // add codeword to voice data unit
    imbe_interleave(frame_body, cw, codeword_ct);

    // after the ninth and final codeword added, dispose of frame
    if (++codeword_ct >= nof_voice_codewords) {
        static const uint64_t hws[2] = { 0x293555ef2c653437LL, 0x293aba93bec26a2bLL };
                int ldu_type = frame_cnt & 1;    // set ldu_type = 0(LDU1) or 1(LDU2)
        const bool* ldu_preset = (ldu_type == 0) ? ldu1_preset : ldu2_preset;
       
        p25_setup_frame_header(frame_body, hws[ldu_type]);
        for (size_t i = 0; i < frame_body.size(); i++) {
            frame_body[i] = frame_body[i] | ldu_preset[i];
        }
        // finally, output the frame
        if (opt_udp_port > 0) {
            // pack the bits into bytes, MSB first
            size_t obuf_ct = 0;
            for (uint32_t i = 0; i < P25_VOICE_FRAME_SIZE; i += 8) {
                uint8_t b =
                    (frame_body[i+0] << 7) +
                    (frame_body[i+1] << 6) +
                    (frame_body[i+2] << 5) +
                    (frame_body[i+3] << 4) +
                    (frame_body[i+4] << 3) +
                    (frame_body[i+5] << 2) +
                    (frame_body[i+6] << 1) +
                    (frame_body[i+7]     );
                obuf[obuf_ct++] = b;
            }
            sendto(write_sock, obuf, obuf_ct, 0, (struct sockaddr*)&write_sock_addr, sizeof(write_sock_addr));
        } else {
            for (uint32_t i = 0; i < P25_VOICE_FRAME_SIZE; i += 2) {
                uint8_t dibit =
                    (frame_body[i+0] << 1) +
                    (frame_body[i+1]     );
                output_queue.push_back(dibit);
            }
        }
        codeword_ct = 0;
        frame_cnt++;
        if (opt_verbose && (frame_cnt % STATS_INTERVAL) == 0) {
            gettimeofday(&tv, &tz);
            int s = tv.tv_sec - oldtv.tv_sec;
            int us = tv.tv_usec - oldtv.tv_usec;
            if (us < 0) {
                us = us + 1000000;
                s  = s - 1;
            }
            float f = us;
            f /= 1000000;
            f += s;
            fprintf (stderr, "time %f peak %5d\n", f / STATS_INTERVAL, peak_amplitude);
            oldtv = tv;
        }
        clear_bits(f_body);
    }
}

void repeater_vocoder::rxchar(char c)
{
    int16_t snd[FRAME];
    int16_t frame_vector[8];
    int u[8];

    if (c < ' ') {
        if (c == '\n') {
            rxbuf[rxbufp] = 0;
            sscanf(rxbuf, "%x %x %x %x %x %x %x %x", &u[0], &u[1], &u[2], &u[3], &u[4], &u[5], &u[6], &u[7]);
            rxbufp = 0;
            // decode 88 bits, outputs 160 sound samples (8000 rate)
            if (d_software_imbe_decoder) {
                voice_codeword cw(voice_codeword_sz);
                imbe_header_encode(cw, u[0], u[1], u[2], u[3], u[4], u[5], u[6], u[7]);
                software_decoder.decode(cw);
                audio_samples *samples = software_decoder.audio();
                for (int i=0; i < FRAME; i++) {
                    if (samples->size() > 0) {
                        snd[i] = (int16_t)(samples->front() * 32768.0);
                        samples->pop_front();
                    } else {
                        snd[i] = 0;
                    }
                }
            } else {
                for (int i=0; i < 8; i++) {
                    frame_vector[i] = u[i];
                }
        /* TEST*/    frame_vector[7] >>= 1;
                vocoder.imbe_decode(frame_vector, snd);
            }
            if (opt_udp_port > 0) {
                sendto(write_sock, snd, FRAME * sizeof(int16_t), 0, (struct sockaddr*)&write_sock_addr, sizeof(write_sock_addr));
            } else {
                // add generated samples to output queue
                for (int i = 0; i < FRAME; i++) {
                    output_queue_decode.push_back(snd[i]);
                }
            }
        }
        return;
    }
    rxbuf[rxbufp++] = c;
    if (rxbufp >= RXBUF_MAX) {
        rxbufp = RXBUF_MAX - 1;
    }
}

void repeater_vocoder::compress_frame(int16_t snd[])
{
    int16_t frame_vector[8];   

    // encode 160 audio samples into 88 bits (u0-u7)
    vocoder.imbe_encode(frame_vector, snd);

    // if dump option, dump u0-u7 to output
    if (opt_dump_raw_vectors) {
        char s[128];
        sprintf(s, "%03x %03x %03x %03x %03x %03x %03x %03x\n", frame_vector[0], frame_vector[1], frame_vector[2], frame_vector[3], frame_vector[4], frame_vector[5], frame_vector[6], frame_vector[7]);
        memcpy(&write_buf[write_bufp], s, strlen(s));
        write_bufp += strlen(s);
        if (write_bufp >= 288) {
            sendto(write_sock, write_buf, 288, 0, (struct sockaddr*)&write_sock_addr, sizeof(write_sock_addr));
            write_bufp = 0;
        }
        return;
    }
    append_imbe_codeword(f_body, frame_vector, codeword_ct);
}

void repeater_vocoder::add_sample(int16_t samp)
{
    // add one sample to 160-sample frame buffer and process if filled
    sampbuf[sampbuf_ct++] = samp;
    if (sampbuf_ct >= FRAME) {
        compress_frame(sampbuf);
        sampbuf_ct = 0;
    }

    // track signal amplitudes
    int16_t asamp = (samp < 0) ? 0 - samp : samp;
    peak = (asamp > peak) ? asamp : peak;
    if (++samp_ct >= SAMP_INTERVAL) {
        peak_amplitude = peak;
        peak = 0;
        samp_ct = 0;
    }
}

void repeater_vocoder::compress_samp(int16_t samp)
{
    // Apply sample rate slew to accomodate sound card rate discrepancy -
    // workaround for USRP underrun problem occurring when sound card
    // capture rate is slower than the correct rate

    // FIXME: autodetect proper value for opt_stretch_amt
    // perhaps by steering the LDU output rate to a 180.0 msec. rate

    stretch_count++;
    if (opt_stretch_amt != 0 && stretch_count >= opt_stretch_amt) {
        stretch_count = 0;
        if (opt_stretch_sign < 0)
            // spill this samp
            return;
        // repeat this samp
        add_sample(samp);
    }
    add_sample(samp);
}

void repeater_vocoder::init_sock(char* udp_host, int udp_port)
{
        memset (&write_sock_addr, 0, sizeof(write_sock_addr));
        write_sock = socket(PF_INET, SOCK_DGRAM, 17);   // UDP socket
        if (write_sock < 0) {
                fprintf(stderr, "repeater_vocoder: socket: %d\n", errno);
                write_sock = 0;
        return;
        }
        if (!inet_aton(udp_host, &write_sock_addr.sin_addr)) {
                fprintf(stderr, "repeater_vocoder: bad IP address\n");
        close(write_sock);
        write_sock = 0;
        return;
    }
        write_sock_addr.sin_family = AF_INET;
        write_sock_addr.sin_port = htons(udp_port);
}

void
repeater_vocoder::forecast(int nof_output_items, gr_vector_int &nof_input_items_reqd)
{
   /* When encoding, this block consumes 8000 symbols/s and produces 4800
    * samples/s. That's a sampling rate of 5/3 or 1.66667.
    *
    * When decoding, the block consumes one line of text per voice codeword.
    * Each line of text is exactly 32 bytes.  It outputs 160 samples for each
    * codeword; the ratio is thus 32/160 = 0.2.
    *
    * Thanks to Matt Mills for catching a bug where this value wasn't set correctly
    */
   const size_t nof_inputs = nof_input_items_reqd.size();
   const int nof_samples_reqd = (opt_encode_flag) ? (1.66667 * nof_output_items) : (0.2 * nof_output_items);
   std::fill(&nof_input_items_reqd[0], &nof_input_items_reqd[nof_inputs], nof_samples_reqd);
}

int
repeater_vocoder::general_work_decode (int noutput_items,
                   gr_vector_int &ninput_items,
                   gr_vector_const_void_star &input_items,
                   gr_vector_void_star &output_items)
{
  const char *in = (const char *) input_items[0];

  for (int i = 0; i < ninput_items[0]; i++){
    rxchar(in[i]);
  }

  // Tell runtime system how many input items we consumed on
  // each input stream.

  consume_each (ninput_items[0]);

  uint16_t *out = reinterpret_cast<uint16_t*>(output_items[0]);
  const int n = std::min(static_cast<int>(output_queue_decode.size()), noutput_items);
  if(0 < n) {
     copy(output_queue_decode.begin(), output_queue_decode.begin() + n, out);
     output_queue_decode.erase(output_queue_decode.begin(), output_queue_decode.begin() + n);
  }
  // Tell runtime system how many output items we produced.
  return n;
}

int
repeater_vocoder::general_work_encode (int noutput_items,
                   gr_vector_int &ninput_items,
                   gr_vector_const_void_star &input_items,
                   gr_vector_void_star &output_items)
{
  const short *in = (const short *) input_items[0];

  for (int i = 0; i < ninput_items[0]; i++){
    compress_samp(in[i]);
  }

  // Tell runtime system how many input items we consumed on
  // each input stream.

  consume_each (ninput_items[0]);

  if (opt_udp_port > 0)        // in udp option, we are a gr sink only
    return 0;

  uint8_t *out = reinterpret_cast<uint8_t*>(output_items[0]);
  const int n = std::min(static_cast<int>(output_queue.size()), noutput_items);
  if(0 < n) {
     copy(output_queue.begin(), output_queue.begin() + n, out);
     output_queue.erase(output_queue.begin(), output_queue.begin() + n);
  }
  // Tell runtime system how many output items we produced.
  return n;
}

int
repeater_vocoder::general_work (int noutput_items,
                   gr_vector_int &ninput_items,
                   gr_vector_const_void_star &input_items,
                   gr_vector_void_star &output_items)
{
    if (opt_encode_flag)
        return general_work_encode(noutput_items, ninput_items, input_items, output_items);
    else
        return general_work_decode(noutput_items, ninput_items, input_items, output_items);
}

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