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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 <stdio.h>
#include <gnuradio/io_signature.h>
#include "estimate_sample_rate_bf_impl.h"
namespace gr {
namespace dab {
estimate_sample_rate_bf::sptr
estimate_sample_rate_bf::make(float expected_sample_rate, int frame_length)
{
return gnuradio::get_initial_sptr
(new estimate_sample_rate_bf_impl(expected_sample_rate, frame_length));
}
/*
* Specify constraints on number of input and output streams.
* This info is used to construct the input and output signatures
* (2nd & 3rd args to gr_block's constructor). The input and
* output signatures are used by the runtime system to
* check that a valid number and type of inputs and outputs
* are connected to this block. In this case, we accept
* only 1 input and 1 output.
*/
static const int MIN_IN = 1; // mininum number of input streams
static const int MAX_IN = 1; // maximum number of input streams
static const int MIN_OUT = 1; // minimum number of output streams
static const int MAX_OUT = 1; // maximum number of output streams
estimate_sample_rate_bf_impl::estimate_sample_rate_bf_impl(float expected_sample_rate, int frame_length)
: gr::sync_block("estimate_sample_rate_bf",
gr::io_signature::make (MIN_IN, MAX_IN, sizeof (char)),
gr::io_signature::make (MIN_OUT, MAX_OUT, sizeof (float))),
d_zeros(0), d_expected_sample_rate(expected_sample_rate), d_real_sample_rate(expected_sample_rate), d_found_first_frame(0), d_frame_length(frame_length)
{
}
/*
* Our virtual destructor.
*/
estimate_sample_rate_bf_impl::~estimate_sample_rate_bf_impl()
{
// nothing else required in this example
}
int
estimate_sample_rate_bf_impl::work(int noutput_items,
gr_vector_const_void_star &input_items,
gr_vector_void_star &output_items)
{
const char *in = (const char *) input_items[0];
float *out = (float *) output_items[0];
int i=0;
if (d_found_first_frame) {
for(i=0; i<noutput_items; i++) {
d_zeros++;
if (*in == 1) {
d_real_sample_rate = (float)d_zeros / (float)d_frame_length * d_expected_sample_rate;
// fprintf(stderr,"estimated sample rate: %f\n", d_real_sample_rate);
d_zeros = 0;
}
in++;
*out++ = d_real_sample_rate;
}
} else {
while (i<noutput_items && d_found_first_frame==0) {
i++;
if (*in == 1)
d_found_first_frame = 1;
in++;
*out++ = d_real_sample_rate;
}
}
// Tell runtime system how many output items we produced.
return i;
}
}
}
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