gr_unpack_k_bits_bb.cc

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/* -*- c++ -*- */
/*
 * 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 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.
 */

#if HAVE_CONFIG_H
#include "config.h"
#endif

#include <gr_unpack_k_bits_bb.h>
#include <gr_io_signature.h>
#include <stdexcept>
#include <iostream>

gr_unpack_k_bits_bb_sptr gr_make_unpack_k_bits_bb (unsigned k)
{
  return gr_unpack_k_bits_bb_sptr (new gr_unpack_k_bits_bb (k));
}


gr_unpack_k_bits_bb::gr_unpack_k_bits_bb (unsigned k)
  : gr_sync_interpolator ("unpack_k_bits_bb",
			  gr_make_io_signature (1, 1, sizeof (unsigned char)),
			  gr_make_io_signature (1, 1, sizeof (unsigned char)),
			  k),
    d_k (k)
{
  if (d_k == 0)
    throw std::out_of_range ("interpolation must be > 0");
}

gr_unpack_k_bits_bb::~gr_unpack_k_bits_bb ()
{
}

int
gr_unpack_k_bits_bb::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];
  unsigned char *out = (unsigned char *) output_items[0];

  int n = 0;
  for (unsigned int i = 0; i < noutput_items/d_k; i++){
    unsigned int t = in[i];
    for (int j = d_k - 1; j >= 0; j--)
      out[n++] = (t >> j) & 0x01;
  }

  assert(n == noutput_items);
  return noutput_items;
}