643 lines
15 KiB
C++
643 lines
15 KiB
C++
/*
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* Copyright (C) 2016-2017 Paul Davis <paul@linuxaudiosystems.com>
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* Copyright (C) 2016-2018 Robin Gareus <robin@gareus.org>
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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 along
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* with this program; if not, write to the Free Software Foundation, Inc.,
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* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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*/
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#include <algorithm>
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#include <boost/math/special_functions/fpclassify.hpp>
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#include <cmath>
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#include <stdlib.h>
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#include "ardour/buffer.h"
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#include "ardour/dB.h"
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#include "ardour/dsp_filter.h"
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#include "ardour/runtime_functions.h"
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#ifdef COMPILER_MSVC
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#include <float.h>
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#define isfinite_local(val) (bool)_finite ((double)val)
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#else
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#define isfinite_local std::isfinite
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#endif
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#ifndef M_PI
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#define M_PI 3.14159265358979323846
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#endif
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using namespace ARDOUR::DSP;
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void
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ARDOUR::DSP::memset (float* data, const float val, const uint32_t n_samples)
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{
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] = val;
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}
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}
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void
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ARDOUR::DSP::mmult (float* data, float* mult, const uint32_t n_samples)
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{
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] *= mult[i];
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}
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}
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float
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ARDOUR::DSP::log_meter (float power)
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{
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// compare to libs/ardour/log_meter.h
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static const float lower_db = -192.f;
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static const float upper_db = 0.f;
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static const float non_linearity = 8.0;
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return (power < lower_db ? 0.0 : powf ((power - lower_db) / (upper_db - lower_db), non_linearity));
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}
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float
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ARDOUR::DSP::log_meter_coeff (float coeff)
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{
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if (coeff <= 0) {
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return 0;
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}
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return log_meter (fast_coefficient_to_dB (coeff));
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}
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void
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ARDOUR::DSP::peaks (const float* data, float& min, float& max, uint32_t n_samples)
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{
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ARDOUR::find_peaks (data, n_samples, &min, &max);
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}
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void
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ARDOUR::DSP::process_map (BufferSet* bufs, const ChanCount& n_out, const ChanMapping& in_map, const ChanMapping& out_map, pframes_t nframes, samplecnt_t offset)
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{
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/* PluginInsert already handles most, in particular `no-inplace` buffers in case
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* or x-over connections, and through connections.
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*
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* This just fills output buffers, forwarding inputs as needed:
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* Input -> plugin-sink == plugin-src -> Output
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*/
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for (DataType::iterator t = DataType::begin (); t != DataType::end (); ++t) {
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for (uint32_t out = 0; out < n_out.get (*t); ++out) {
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bool valid;
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uint32_t out_idx = out_map.get (*t, out, &valid);
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if (!valid) {
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continue;
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}
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uint32_t in_idx = in_map.get (*t, out, &valid);
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if (!valid) {
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bufs->get_available (*t, out_idx).silence (nframes, offset);
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continue;
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}
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if (in_idx != out_idx) {
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bufs->get_available (*t, out_idx).read_from (bufs->get_available (*t, in_idx), nframes, offset, offset);
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}
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}
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}
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}
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LowPass::LowPass (double samplerate, float freq)
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: _rate (samplerate)
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, _z (0)
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{
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set_cutoff (freq);
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}
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void
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LowPass::set_cutoff (float freq)
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{
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_a = 1.f - expf (-2.f * M_PI * freq / _rate);
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}
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void
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LowPass::proc (float* data, const uint32_t n_samples)
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{
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// localize variables
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const float a = _a;
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float z = _z;
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] += a * (data[i] - z);
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z = data[i];
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}
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_z = z;
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if (!isfinite_local (_z)) {
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_z = 0;
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} else if (!boost::math::isnormal (_z)) {
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_z = 0;
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}
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}
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void
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LowPass::ctrl (float* data, const float val, const uint32_t n_samples)
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{
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// localize variables
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const float a = _a;
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float z = _z;
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] += a * (val - z);
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z = data[i];
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}
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_z = z;
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}
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///////////////////////////////////////////////////////////////////////////////
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Biquad::Biquad (double samplerate)
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: _rate (samplerate)
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, _z1 (0.0)
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, _z2 (0.0)
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, _a1 (0.0)
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, _a2 (0.0)
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, _b0 (1.0)
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, _b1 (0.0)
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, _b2 (0.0)
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{
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}
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Biquad::Biquad (const Biquad& other)
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: _rate (other._rate)
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, _z1 (0.0)
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, _z2 (0.0)
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, _a1 (other._a1)
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, _a2 (other._a2)
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, _b0 (other._b0)
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, _b1 (other._b1)
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, _b2 (other._b2)
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{
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}
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void
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Biquad::run (float* data, const uint32_t n_samples)
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{
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for (uint32_t i = 0; i < n_samples; ++i) {
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const float xn = data[i];
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const float z = _b0 * xn + _z1;
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_z1 = _b1 * xn - _a1 * z + _z2;
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_z2 = _b2 * xn - _a2 * z;
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data[i] = z;
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}
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if (!isfinite_local (_z1)) {
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_z1 = 0;
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} else if (!boost::math::isnormal (_z1)) {
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_z1 = 0;
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}
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if (!isfinite_local (_z2)) {
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_z2 = 0;
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} else if (!boost::math::isnormal (_z2)) {
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_z2 = 0;
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}
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}
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void
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Biquad::configure (double a1, double a2, double b0, double b1, double b2)
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{
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_a1 = a1;
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_a2 = a2;
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_b0 = b0;
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_b1 = b1;
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_b2 = b2;
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}
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void
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Biquad::configure (Biquad const& other)
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{
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_a1 = other._a1;
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_a2 = other._a2;
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_b0 = other._b0;
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_b1 = other._b1;
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_b2 = other._b2;
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}
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void
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Biquad::set_vicanek_poles (const double W0, const double Q, const double A)
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{
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/* https://www.vicanek.de/articles/BiquadFits.pdf */
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const double Q2 = Q * Q;
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const double AA = A * A;
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const double p = 1. / (4 * AA * Q2);
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_a2 = exp (-.5 * W0 / (A * Q));
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_a1 = p <= 1.
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? -2 * _a2 * cos (W0 * sqrt (1 - p))
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: -2 * _a2 * cosh (W0 * sqrt (p - 1));
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_a2 = _a2 * _a2;
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}
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void
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Biquad::calc_vicanek (const double W0, double& A0, double& A1, double& A2, double& phi0, double& phi1, double& phi2)
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{
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#define SQR(x) ((x) * (x))
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A0 = SQR (1. + _a1 + _a2);
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A1 = SQR (1. - _a1 + _a2);
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A2 = -4 * _a2;
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phi1 = SQR (sin (.5 * W0));
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phi0 = 1.0 - phi1;
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phi2 = 4 * phi0 * phi1;
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#undef SQR
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}
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void
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Biquad::compute (Type type, double freq, double Q, double gain)
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{
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if (Q <= .001) {
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Q = 0.001;
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}
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if (freq <= 1.) {
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freq = 1.;
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}
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if (freq >= 0.4998 * _rate) {
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freq = 0.4998 * _rate;
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}
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/* Compute biquad filter settings.
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* Based on 'Cookbook formulae for audio EQ biquad filter coefficents'
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* by Robert Bristow-Johnson
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*/
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const double A = pow (10.0, (gain / 40.0));
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const double W0 = (2.0 * M_PI * freq) / _rate;
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const double sinW0 = sin (W0);
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const double cosW0 = cos (W0);
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const double alpha = sinW0 / (2.0 * Q);
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const double beta = sqrt (A) / Q;
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double _a0;
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double A0, A1, A2;
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double phi0, phi1, phi2;
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switch (type) {
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case LowPass:
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_b0 = (1.0 - cosW0) / 2.0;
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_b1 = 1.0 - cosW0;
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_b2 = (1.0 - cosW0) / 2.0;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case HighPass:
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_b0 = (1.0 + cosW0) / 2.0;
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_b1 = -(1.0 + cosW0);
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_b2 = (1.0 + cosW0) / 2.0;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case BandPassSkirt: /* Constant skirt gain, peak gain = Q */
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_b0 = sinW0 / 2.0;
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_b1 = 0.0;
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_b2 = -sinW0 / 2.0;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case BandPass0dB: /* Constant 0 dB peak gain */
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_b0 = alpha;
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_b1 = 0.0;
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_b2 = -alpha;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case Notch:
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_b0 = 1.0;
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_b1 = -2.0 * cosW0;
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_b2 = 1.0;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case AllPass:
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_b0 = 1.0 - alpha;
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_b1 = -2.0 * cosW0;
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_b2 = 1.0 + alpha;
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_a0 = 1.0 + alpha;
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - alpha;
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break;
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case Peaking:
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_b0 = 1.0 + (alpha * A);
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_b1 = -2.0 * cosW0;
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_b2 = 1.0 - (alpha * A);
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_a0 = 1.0 + (alpha / A);
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_a1 = -2.0 * cosW0;
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_a2 = 1.0 - (alpha / A);
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break;
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case LowShelf:
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_b0 = A * ((A + 1) - ((A - 1) * cosW0) + (beta * sinW0));
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_b1 = (2.0 * A) * ((A - 1) - ((A + 1) * cosW0));
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_b2 = A * ((A + 1) - ((A - 1) * cosW0) - (beta * sinW0));
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_a0 = (A + 1) + ((A - 1) * cosW0) + (beta * sinW0);
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_a1 = -2.0 * ((A - 1) + ((A + 1) * cosW0));
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_a2 = (A + 1) + ((A - 1) * cosW0) - (beta * sinW0);
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break;
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case HighShelf:
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_b0 = A * ((A + 1) + ((A - 1) * cosW0) + (beta * sinW0));
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_b1 = -(2.0 * A) * ((A - 1) + ((A + 1) * cosW0));
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_b2 = A * ((A + 1) + ((A - 1) * cosW0) - (beta * sinW0));
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_a0 = (A + 1) - ((A - 1) * cosW0) + (beta * sinW0);
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_a1 = 2.0 * ((A - 1) - ((A + 1) * cosW0));
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_a2 = (A + 1) - ((A - 1) * cosW0) - (beta * sinW0);
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break;
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case MatchedHighPass:
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_a0 = 1.0;
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set_vicanek_poles (W0, Q);
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calc_vicanek (W0, A0, A1, A2, phi0, phi1, phi2);
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_b0 = sqrt (A0 * phi0 + A1 * phi1 + A2 * phi2) / (4 * phi1) * Q;
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_b1 = -2 * _b0;
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_b2 = _b0;
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break;
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case MatchedLowPass:
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_a0 = 1.0;
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set_vicanek_poles (W0, Q);
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calc_vicanek (W0, A0, A1, A2, phi0, phi1, phi2);
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{
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const double B0_2 = 1 + _a1 + _a2; // = sqrt (B0)
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const double B1 = ((A0 * phi0 + A1 * phi1 + A2 * phi2) * Q * Q - A0 * phi0) / phi1;
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_b0 = .5 * (B0_2 + sqrt (B1));
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_b1 = B0_2 - _b0;
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_b2 = 0;
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}
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break;
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case MatchedBandPass0dB: /* Constant 0 dB peak gain */
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_a0 = 1.0;
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set_vicanek_poles (W0, Q);
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{
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float fq = 2 * freq / _rate;
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float fq2 = fq * fq;
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_b1 = -.5 * (1 - _a1 + _a2) * fq / Q / sqrt ((1 - fq2) * (1 - fq2) + fq2 / (Q * Q));
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_b0 = .5 * ((1 + _a1 + _a2) / (W0 * Q) - _b1);
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_b2 = -_b0 - _b1;
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}
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break;
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case MatchedPeaking:
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_a0 = 1.0;
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set_vicanek_poles (W0, Q, A);
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calc_vicanek (W0, A0, A1, A2, phi0, phi1, phi2);
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{
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const double AA = A * A;
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const double AAAA = AA * AA;
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const double R1 = (phi0 * A0 + phi1 * A1 + phi2 * A2) * AAAA;
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const double R2 = (A1 - A0 + 4 * (phi0 - phi1) * A2) * AAAA;
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const double B0 = A0;
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const double B2 = (R1 - phi1 * R2 - B0) / (4 * phi1 * phi1);
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const double B1 = R2 + B0 + 4 * (phi1 - phi0) * B2;
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const double B0_2 = 1 + _a1 + _a2; // = sqrt (B0)
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_b1 = .5 * (B0_2 - sqrt (B1));
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const double w = B0_2 - _b1;
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_b0 = .5 * (w + sqrt (w * w + B2));
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_b2 = -B2 / (4 * _b0);
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}
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break;
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default:
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abort (); /*NOTREACHED*/
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break;
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}
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_b0 /= _a0;
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_b1 /= _a0;
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_b2 /= _a0;
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_a1 /= _a0;
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_a2 /= _a0;
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}
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float
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Biquad::dB_at_freq (float freq) const
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{
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const double W0 = (2.0 * M_PI * freq) / _rate;
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const float c1 = cosf (W0);
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const float s1 = sinf (W0);
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const float A = _b0 + _b2;
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const float B = _b0 - _b2;
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const float C = 1.0 + _a2;
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const float D = 1.0 - _a2;
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const float a = A * c1 + _b1;
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const float b = B * s1;
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const float c = C * c1 + _a1;
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const float d = D * s1;
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#define SQUARE(x) ((x) * (x))
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float rv = 20.f * log10f (sqrtf ((SQUARE (a) + SQUARE (b)) * (SQUARE (c) + SQUARE (d))) / (SQUARE (c) + SQUARE (d)));
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if (!isfinite_local (rv)) {
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rv = 0;
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}
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return std::min (120.f, std::max (-120.f, rv));
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}
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Glib::Threads::Mutex FFTSpectrum::fft_planner_lock;
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FFTSpectrum::FFTSpectrum (uint32_t window_size, double rate)
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: hann_window (0)
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{
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init (window_size, rate);
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}
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FFTSpectrum::~FFTSpectrum ()
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{
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{
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Glib::Threads::Mutex::Lock lk (fft_planner_lock);
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fftwf_destroy_plan (_fftplan);
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}
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fftwf_free (_fft_data_in);
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fftwf_free (_fft_data_out);
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free (_fft_power);
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free (hann_window);
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}
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void
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FFTSpectrum::init (uint32_t window_size, double rate)
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{
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assert (window_size > 0);
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Glib::Threads::Mutex::Lock lk (fft_planner_lock);
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_fft_window_size = window_size;
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_fft_data_size = window_size / 2;
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_fft_freq_per_bin = rate / _fft_data_size / 2.f;
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_fft_data_in = (float*)fftwf_malloc (sizeof (float) * _fft_window_size);
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_fft_data_out = (float*)fftwf_malloc (sizeof (float) * _fft_window_size);
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_fft_power = (float*)malloc (sizeof (float) * _fft_data_size);
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reset ();
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_fftplan = fftwf_plan_r2r_1d (_fft_window_size, _fft_data_in, _fft_data_out, FFTW_R2HC, FFTW_MEASURE);
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hann_window = (float*)malloc (sizeof (float) * window_size);
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double sum = 0.0;
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for (uint32_t i = 0; i < window_size; ++i) {
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hann_window[i] = 0.5f - (0.5f * (float)cos (2.0f * M_PI * (float)i / (float)(window_size)));
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sum += hann_window[i];
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}
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const double isum = 2.0 / sum;
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for (uint32_t i = 0; i < window_size; ++i) {
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hann_window[i] *= isum;
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}
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}
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void
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FFTSpectrum::reset ()
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{
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for (uint32_t i = 0; i < _fft_data_size; ++i) {
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_fft_power[i] = 0;
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}
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for (uint32_t i = 0; i < _fft_window_size; ++i) {
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_fft_data_out[i] = 0;
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}
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}
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void
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FFTSpectrum::set_data_hann (float const* const data, uint32_t n_samples, uint32_t offset)
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{
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assert (n_samples + offset <= _fft_window_size);
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for (uint32_t i = 0; i < n_samples; ++i) {
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_fft_data_in[i + offset] = data[i] * hann_window[i + offset];
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}
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}
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void
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FFTSpectrum::execute ()
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{
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fftwf_execute (_fftplan);
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_fft_power[0] = _fft_data_out[0] * _fft_data_out[0];
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#define FRe (_fft_data_out[i])
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#define FIm (_fft_data_out[_fft_window_size - i])
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for (uint32_t i = 1; i < _fft_data_size - 1; ++i) {
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_fft_power[i] = (FRe * FRe) + (FIm * FIm);
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//_fft_phase[i] = atan2f (FIm, FRe);
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}
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#undef FRe
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#undef FIm
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}
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float
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FFTSpectrum::power_at_bin (const uint32_t b, const float norm) const
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{
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assert (b < _fft_data_size);
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const float a = _fft_power[b] * norm;
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return a > 1e-12 ? 10.0 * fast_log10 (a) : -INFINITY;
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}
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Generator::Generator ()
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: _type (UniformWhiteNoise)
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, _rseed (1)
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{
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set_type (UniformWhiteNoise);
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}
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void
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Generator::set_type (Generator::Type t)
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{
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_type = t;
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_b0 = _b1 = _b2 = _b3 = _b4 = _b5 = _b6 = 0;
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_pass = false;
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_rn = 0;
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}
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void
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Generator::run (float* data, const uint32_t n_samples)
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{
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switch (_type) {
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default:
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case UniformWhiteNoise:
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] = randf ();
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}
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break;
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case GaussianWhiteNoise:
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for (uint32_t i = 0; i < n_samples; ++i) {
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data[i] = 0.7079f * grandf ();
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}
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break;
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case PinkNoise:
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for (uint32_t i = 0; i < n_samples; ++i) {
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const float white = .39572f * randf ();
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_b0 = .99886f * _b0 + white * .0555179f;
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_b1 = .99332f * _b1 + white * .0750759f;
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_b2 = .96900f * _b2 + white * .1538520f;
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_b3 = .86650f * _b3 + white * .3104856f;
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_b4 = .55000f * _b4 + white * .5329522f;
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_b5 = -.7616f * _b5 - white * .0168980f;
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data[i] = _b0 + _b1 + _b2 + _b3 + _b4 + _b5 + _b6 + white * 0.5362f;
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_b6 = white * 0.115926f;
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}
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break;
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}
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}
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inline uint32_t
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Generator::randi ()
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{
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// 31bit Park-Miller-Carta Pseudo-Random Number Generator
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uint32_t hi, lo;
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lo = 16807 * (_rseed & 0xffff);
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hi = 16807 * (_rseed >> 16);
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lo += (hi & 0x7fff) << 16;
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lo += hi >> 15;
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lo = (lo & 0x7fffffff) + (lo >> 31);
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return (_rseed = lo);
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}
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inline float
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Generator::grandf ()
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{
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float x1, x2, r;
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if (_pass) {
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_pass = false;
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return _rn;
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}
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do {
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x1 = randf ();
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x2 = randf ();
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r = x1 * x1 + x2 * x2;
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} while ((r >= 1.0f) || (r < 1e-22f));
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r = sqrtf (-2.f * logf (r) / r);
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_pass = true;
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_rn = r * x2;
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return r * x1;
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}
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