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/* -*- c++ -*- */
/*
* Copyright 2004 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 <gnuradio/io_signature.h>
#include "ofdm_remove_first_symbol_vcc_impl.h"
namespace gr {
namespace dab {
ofdm_remove_first_symbol_vcc::sptr
ofdm_remove_first_symbol_vcc::make(unsigned int vlen)
{
return gnuradio::get_initial_sptr
(new ofdm_remove_first_symbol_vcc_impl(vlen));
}
ofdm_remove_first_symbol_vcc_impl::ofdm_remove_first_symbol_vcc_impl(unsigned int vlen)
: gr::block("ofdm_remove_first_symbol_vcc",
gr::io_signature::make (1, 1, sizeof(gr_complex)*vlen),
gr::io_signature::make (1, 1, sizeof(gr_complex)*vlen)),
d_vlen(vlen), d_start(0)
{
set_tag_propagation_policy(TPP_DONT);
}
void
ofdm_remove_first_symbol_vcc_impl::forecast (int noutput_items, gr_vector_int &ninput_items_required)
{
//int in_req = noutput_items; + 1 + noutput_items/76; // at most every 76th symbol is thrown away (depends on the DAB mode)
int in_req = noutput_items; // altough more may be needed, try to produce output even with only one input - if it's a pilot, we can just consume it ...
unsigned ninputs = ninput_items_required.size ();
for (unsigned int i = 0; i < ninputs; i++)
ninput_items_required[i] = in_req;
}
int
ofdm_remove_first_symbol_vcc_impl::general_work (int noutput_items,
gr_vector_int &ninput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
const gr_complex *iptr = (const gr_complex *) input_items[0];
gr_complex *optr = (gr_complex *) output_items[0];
int n_consumed = 0;
int n_produced = 0;
std::vector<int> tag_positions;
int next_tag_position = -1;
int next_tag_position_index = -1;
// Get all stream tags with key "first", and make a vector of the positions.
// "next_tag_position" contains the position within "iptr where the next "dab_sync" stream tag is found
std::vector<tag_t> tags;
get_tags_in_range(tags, 0, nitems_read(0), nitems_read(0) + ninput_items[0], pmt::mp("first"));
for(int i=0;i<tags.size();i++) {
int current;
current = tags[i].offset - nitems_read(0);
tag_positions.push_back(current);
next_tag_position_index = 0;
}
if(next_tag_position_index >= 0) {
next_tag_position = tag_positions[next_tag_position_index];
}
for (n_consumed=0; n_consumed<ninput_items[0] && n_produced<noutput_items; n_consumed++) {
if (next_tag_position == n_consumed) { /* frame_start */
next_tag_position_index++;
if (next_tag_position_index == tag_positions.size()) {
next_tag_position_index = -1;
next_tag_position = -1;
}
else {
next_tag_position = tag_positions[next_tag_position_index];
}
// Action when stream tags is found:
d_start = 1;
iptr += d_vlen;
//
} else {
if (d_start == 1)
add_item_tag(0, nitems_written(0) + n_produced, pmt::intern("first"), pmt::intern(""), pmt::intern("ofdm_remove_first_symbol_vcc"));
n_produced++;
d_start = 0;
for (unsigned int j=0; j<d_vlen; j++)
*optr++ = *iptr++;
}
}
// printf("ninput_items[0]: %d, ninput_items[1]: %d, noutput_items: %d, consumed: %d, produced: %d\n", ninput_items[0], ninput_items[1], noutput_items, n_consumed, n_produced);
consume_each(n_consumed);
return n_produced;
}
}
}
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