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/*
* This file is part of libsidplayfp, a SID player engine.
*
* Copyright 2012-2013 Leandro Nini <drfiemost@users.sourceforge.net>
* Copyright 2007-2010 Antti Lankila
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <map>
#include <memory>
#include <ctime>
#include <iostream>
#include <iomanip>
#include <cmath>
#include "../siddefs-fp.h"
#include "Resampler.h"
#include "TwoPassSincResampler.h"
/**
* Simple sin waveform in, power output measurement function.
* It would be far better to use FFT.
*/
int main(int argc, const char* argv[])
{
const double RATE = 985248.4;
const int RINGSIZE = 2048;
std::auto_ptr<reSIDfp::TwoPassSincResampler> r(reSIDfp::TwoPassSincResampler::create(RATE, 48000.0, 20000.0));
std::map<double, double> results;
clock_t start = clock();
for (double freq = 1000.; freq < RATE / 2.; freq *= 1.01)
{
/* prefill resampler buffer */
int k = 0;
double omega = 2 * M_PI * freq / RATE;
for (int j = 0; j < RINGSIZE; j ++)
{
int signal = static_cast<int>(32768.0 * sin(k++ * omega) * sqrt(2));
r->input(signal);
}
int n = 0;
float pwr = 0;
/* Now, during measurement stage, put 100 cycles of waveform through filter. */
for (int j = 0; j < 100000; j ++)
{
int signal = static_cast<int>(32768.0 * sin(k++ * omega) * sqrt(2));
if (r->input(signal))
{
float out = r->output();
pwr += out * out;
n += 1;
}
}
results.insert(std::make_pair(freq, 10 * log10(pwr / n)));
}
clock_t end = clock();
for (std::map<double, double>::iterator it = results.begin(); it != results.end(); ++it)
{
std::cout << std::fixed << std::setprecision(0) << std::setw(6) << (*it).first << " Hz " << (*it).second << " dB" << std::endl;
}
std::cout << "Filtering time " << (end - start) * 1000. / CLOCKS_PER_SEC << " ms" << std::endl;
}
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