3 * Copyright 2004 Free Software Foundation, Inc.
5 * This file is part of GNU Radio
7 * GNU Radio is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 3, or (at your option)
12 * GNU Radio is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with GNU Radio; see the file COPYING. If not, write to
19 * the Free Software Foundation, Inc., 51 Franklin Street,
20 * Boston, MA 02110-1301, USA.
27 #include <gr_sync_decimator.h>
29 gr_sync_decimator::gr_sync_decimator (const std::string &name,
30 gr_io_signature_sptr input_signature,
31 gr_io_signature_sptr output_signature,
33 : gr_sync_block (name, input_signature, output_signature)
35 set_decimation (decimation);
39 gr_sync_decimator::forecast (int noutput_items, gr_vector_int &ninput_items_required)
41 unsigned ninputs = ninput_items_required.size ();
42 for (unsigned i = 0; i < ninputs; i++)
43 ninput_items_required[i] = fixed_rate_noutput_to_ninput(noutput_items);
47 gr_sync_decimator::fixed_rate_noutput_to_ninput(int noutput_items)
49 return noutput_items * decimation() + history() - 1;
53 gr_sync_decimator::fixed_rate_ninput_to_noutput(int ninput_items)
55 return std::max(0, ninput_items - (int)history() + 1) / decimation();
59 gr_sync_decimator::general_work (int noutput_items,
60 gr_vector_int &ninput_items,
61 gr_vector_const_void_star &input_items,
62 gr_vector_void_star &output_items)
64 int r = work (noutput_items, input_items, output_items);
66 consume_each (r * decimation ());