88 lines
2.7 KiB
Plaintext
88 lines
2.7 KiB
Plaintext
/*
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* This file is part of libsidplayfp, a SID player engine.
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*
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* Copyright 2012-2013 Leandro Nini <drfiemost@users.sourceforge.net>
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* Copyright 2007-2010 Antti Lankila
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
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*/
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#include <map>
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#include <memory>
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#include <ctime>
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#include <iostream>
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#include <iomanip>
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#include <cmath>
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#include "siddefs-fp.h"
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#include "Resampler.h"
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#include "TwoPassSincResampler.h"
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/**
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* Simple sin waveform in, power output measurement function.
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* It would be far better to use FFT.
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*/
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int main(int argc, const char* argv[])
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{
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const double RATE = 985248.4;
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const int RINGSIZE = 2048;
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std::auto_ptr<reSIDfp::TwoPassSincResampler> r(reSIDfp::TwoPassSincResampler::create(RATE, 48000.0, 20000.0));
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std::map<double, double> results;
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clock_t start = clock();
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for (double freq = 1000.; freq < RATE / 2.; freq *= 1.01)
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{
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/* prefill resampler buffer */
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int k = 0;
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double omega = 2 * M_PI * freq / RATE;
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for (int j = 0; j < RINGSIZE; j ++)
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{
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int signal = static_cast<int>(32768.0 * sin(k++ * omega) * sqrt(2));
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r->input(signal);
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}
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int n = 0;
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float pwr = 0;
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/* Now, during measurement stage, put 100 cycles of waveform through filter. */
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for (int j = 0; j < 100000; j ++)
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{
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int signal = static_cast<int>(32768.0 * sin(k++ * omega) * sqrt(2));
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if (r->input(signal))
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{
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float out = r->output();
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pwr += out * out;
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n += 1;
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}
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}
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results.insert(std::make_pair(freq, 10 * log10(pwr / n)));
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}
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clock_t end = clock();
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for (std::map<double, double>::iterator it = results.begin(); it != results.end(); ++it)
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{
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std::cout << std::fixed << std::setprecision(0) << std::setw(6) << (*it).first << " Hz " << (*it).second << " dB" << std::endl;
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}
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std::cout << "Filtering time " << (end - start) * 1000. / CLOCKS_PER_SEC << " ms" << std::endl;
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}
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