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/* -*- c++ -*- */
/*
* Copyright 2007,2010,2013 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "peak_detector2_fb_impl.h"
#include <gr_io_signature.h>
#include <string.h>
namespace gr {
namespace blocks {
peak_detector2_fb::sptr
peak_detector2_fb::make(float threshold_factor_rise,
int look_ahead, float alpha)
{
return gnuradio::get_initial_sptr
(new peak_detector2_fb_impl(threshold_factor_rise,
look_ahead, alpha));
}
peak_detector2_fb_impl::peak_detector2_fb_impl(float threshold_factor_rise,
int look_ahead, float alpha)
: gr_sync_block("peak_detector2_fb",
gr_make_io_signature(1, 1, sizeof(float)),
gr_make_io_signature2(1, 2, sizeof(char), sizeof(float))),
d_threshold_factor_rise(threshold_factor_rise),
d_look_ahead(look_ahead), d_alpha(alpha), d_avg(0.0f), d_found(false)
{
}
peak_detector2_fb_impl::~peak_detector2_fb_impl()
{
}
int
peak_detector2_fb_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
float *iptr = (float *)input_items[0];
char *optr = (char *)output_items[0];
assert(noutput_items >= 2);
memset(optr, 0, noutput_items*sizeof(char));
for(int i = 0; i < noutput_items; i++) {
if(!d_found) {
// Have not yet detected presence of peak
if(iptr[i] > d_avg * (1.0f + d_threshold_factor_rise)) {
d_found = true;
d_look_ahead_remaining = d_look_ahead;
d_peak_val = -(float)INFINITY;
}
else {
d_avg = d_alpha*iptr[i] + (1.0f - d_alpha)*d_avg;
}
}
else {
// Detected presence of peak
if(iptr[i] > d_peak_val) {
d_peak_val = iptr[i];
d_peak_ind = i;
}
else if(d_look_ahead_remaining <= 0) {
optr[d_peak_ind] = 1;
d_found = false;
d_avg = iptr[i];
}
// Have not yet located peak, loop and keep searching.
d_look_ahead_remaining--;
}
// Every iteration of the loop, write debugging signal out if
// connected:
if(output_items.size() == 2) {
float *sigout = (float *)output_items[1];
sigout[i] = d_avg;
}
} // loop
if(!d_found)
return noutput_items;
// else if detected presence, keep searching during the next call to work.
int tmp = d_peak_ind;
d_peak_ind = 1;
return tmp - 1;
}
} /* namespace blocks */
} /* namespace gr */
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