diff options
Diffstat (limited to 'gr-blocks/lib/peak_detector2_fb_impl.cc')
-rw-r--r-- | gr-blocks/lib/peak_detector2_fb_impl.cc | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/gr-blocks/lib/peak_detector2_fb_impl.cc b/gr-blocks/lib/peak_detector2_fb_impl.cc new file mode 100644 index 000000000..0d375c3ba --- /dev/null +++ b/gr-blocks/lib/peak_detector2_fb_impl.cc @@ -0,0 +1,118 @@ +/* -*- 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 */ + + |