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* LinuxSampler - modular, streaming capable sampler * |
* LinuxSampler - modular, streaming capable sampler * |
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* * |
* * |
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* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * |
* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * |
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* Copyright (C) 2005 Christian Schoenebeck * |
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* Copyright (C) 2006-2011 Christian Schoenebeck and Andreas Persson * |
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* * |
* * |
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* This program is free software; you can redistribute it and/or modify * |
* 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 * |
* it under the terms of the GNU General Public License as published by * |
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#include "../../common/global.h" |
#include "../../common/global.h" |
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#if DEBUG_HEADERS |
#include <gig.h> |
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# warning Filter.h included |
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#endif // DEBUG_HEADERS |
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#include "../common/BiquadFilter.h" |
#include <cmath> |
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// TODO: Gigasampler's "Turbo Lowpass" and "Bandreject" filters not implemented yet |
/* TODO: This file contains both generic filters (used by the sfz |
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engine) and gig specific filters. It should probably be split up, |
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and the generic parts should be moved out of the gig directory. */ |
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/* |
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* The formulas for the biquad coefficients come from Robert |
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* Bristow-Johnson's Audio EQ Cookbook. The one pole filter formulas |
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* come from a post on musicdsp.org. The one poles, biquads and |
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* cascaded biquads are modeled after output from Dimension LE and SFZ |
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* Player. The gig filters are modeled after output from GigaStudio. |
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*/ |
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namespace LinuxSampler { |
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#include "../../lib/fileloader/libgig/gig.h" |
/** |
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* Filter state and parameters for a biquad filter. |
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*/ |
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class BiquadFilterData { |
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public: |
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float b0, b1, b2; |
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float a1, a2; |
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#define LSF_BW 0.9 |
float x1, x2; |
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#define LSF_FB 0.9f |
float y1, y2; |
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}; |
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namespace LinuxSampler { namespace gig { |
/** |
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* Filter state and parameters for cascaded biquad filters and gig |
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* engine filters. |
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*/ |
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class FilterData : public BiquadFilterData |
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{ |
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public: |
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union { |
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// gig filter parameters |
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struct { |
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float a3; |
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float x3; |
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float y3; |
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float scale; |
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float b20; |
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float y21, y22, y23; |
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}; |
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// cascaded biquad parameters |
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struct { |
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BiquadFilterData d2; |
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BiquadFilterData d3; |
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}; |
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}; |
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}; |
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/** |
/** |
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* These are filters similar to the ones from Gigasampler. |
* Abstract base class for all filter implementations. |
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*/ |
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class FilterBase { |
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public: |
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virtual float Apply(FilterData& d, float x) const = 0; |
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virtual void SetParameters(FilterData& d, float fc, float r, |
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float fs) const = 0; |
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virtual void Reset(FilterData& d) const = 0; |
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protected: |
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void KillDenormal(float& f) const { |
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f += 1e-18f; |
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f -= 1e-18f; |
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} |
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}; |
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/** |
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* One-pole lowpass filter. |
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*/ |
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class LowpassFilter1p : public FilterBase { |
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public: |
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float Apply(FilterData& d, float x) const { |
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float y = x + d.a1 * (x - d.y1); // d.b0 * x - d.a1 * d.y1; |
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KillDenormal(y); |
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d.y1 = y; |
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return y; |
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} |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float c = 2 - cos(omega); |
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d.a1 = -(c - sqrt(c * c - 1)); |
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// d.b0 = 1 + d.a1; |
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} |
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void Reset(FilterData& d) const { |
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d.y1 = 0; |
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} |
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}; |
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/** |
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* One pole highpass filter. |
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*/ |
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class HighpassFilter1p : public FilterBase { |
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public: |
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float Apply(FilterData& d, float x) const { |
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// d.b0 * x + d.b1 * d.x1 - d.a1 * d.y1; |
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float y = d.a1 * (-x + d.x1 - d.y1); |
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KillDenormal(y); |
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d.x1 = x; |
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d.y1 = y; |
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return y; |
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} |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float c = 2 - cos(omega); |
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d.a1 = -(c - sqrt(c * c - 1)); |
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// d.b0 = -d.a1 |
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// d.b1 = d.a1 |
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} |
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void Reset(FilterData& d) const { |
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d.x1 = 0; |
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d.y1 = 0; |
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} |
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}; |
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/** |
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* Base class for biquad filter implementations. |
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*/ |
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class BiquadFilter : public FilterBase { |
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protected: |
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float ApplyBQ(BiquadFilterData& d, float x) const { |
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float y = d.b0 * x + d.b1 * d.x1 + d.b2 * d.x2 + |
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d.a1 * d.y1 + d.a2 * d.y2; |
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KillDenormal(y); |
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d.x2 = d.x1; |
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d.x1 = x; |
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d.y2 = d.y1; |
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d.y1 = y; |
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return y; |
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} |
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public: |
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float Apply(FilterData& d, float x) const { |
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return ApplyBQ(d, x); |
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} |
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void Reset(FilterData& d) const { |
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d.x1 = d.x2 = 0; |
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d.y1 = d.y2 = 0; |
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} |
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}; |
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/** |
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* Base class for cascaded double biquad filter (four poles). |
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*/ |
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class DoubleBiquadFilter : public BiquadFilter { |
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public: |
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float Apply(FilterData& d, float x) const { |
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return ApplyBQ(d.d2, BiquadFilter::Apply(d, x)); |
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} |
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void Reset(FilterData& d) const { |
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BiquadFilter::Reset(d); |
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d.d2.x1 = d.d2.x2 = 0; |
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d.d2.y1 = d.d2.y2 = 0; |
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} |
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}; |
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/** |
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* Base class for cascaded triple biquad filter (six poles). |
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*/ |
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class TripleBiquadFilter : public DoubleBiquadFilter { |
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public: |
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float Apply(FilterData& d, float x) const { |
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return ApplyBQ(d.d3, DoubleBiquadFilter::Apply(d, x)); |
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} |
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void Reset(FilterData& d) const { |
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DoubleBiquadFilter::Reset(d); |
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d.d3.x1 = d.d3.x2 = 0; |
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d.d3.y1 = d.d3.y2 = 0; |
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} |
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}; |
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/** @brief Lowpass Filter |
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* |
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* Lowpass filter based on biquad filter implementation. |
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*/ |
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class LowpassFilter : public BiquadFilter { |
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public: |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2 * exp(-M_LN10 / 20 * r); |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r * (1.0 - cs) * 0.5; |
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d.b1 = a0r * (1.0 - cs); |
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d.b2 = a0r * (1.0 - cs) * 0.5; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Four pole lowpass filter |
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* |
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* Lowpass filter based on two cascaded biquad filters. |
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*/ |
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class LowpassFilter4p : public DoubleBiquadFilter { |
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public: |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2; |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r * (1.0 - cs) * 0.5; |
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d.b1 = a0r * (1.0 - cs); |
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d.b2 = a0r * (1.0 - cs) * 0.5; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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alpha *= exp(-M_LN10 / 20 * r); |
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a0r = 1.0 / (1.0 + alpha); |
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d.d2.b0 = a0r * (1.0 - cs) * 0.5; |
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d.d2.b1 = a0r * (1.0 - cs); |
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d.d2.b2 = a0r * (1.0 - cs) * 0.5; |
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d.d2.a1 = a0r * (2.0 * cs); |
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d.d2.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Six pole lowpass filter |
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* |
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* Lowpass filter based on three cascaded biquad filters. |
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*/ |
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class LowpassFilter6p : public TripleBiquadFilter { |
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public: |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2; |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = d.d2.b0 = a0r * (1.0 - cs) * 0.5; |
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d.b1 = d.d2.b1 = a0r * (1.0 - cs); |
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d.b2 = d.d2.b2 = a0r * (1.0 - cs) * 0.5; |
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d.a1 = d.d2.a1 = a0r * (2.0 * cs); |
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d.a2 = d.d2.a2 = a0r * (alpha - 1.0); |
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alpha *= exp(-M_LN10 / 20 * r); |
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a0r = 1.0 / (1.0 + alpha); |
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d.d3.b0 = a0r * (1.0 - cs) * 0.5; |
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d.d3.b1 = a0r * (1.0 - cs); |
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d.d3.b2 = a0r * (1.0 - cs) * 0.5; |
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d.d3.a1 = a0r * (2.0 * cs); |
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d.d3.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Bandpass filter |
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* |
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* Bandpass filter based on biquad filter implementation. |
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*/ |
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class BandpassFilter : public BiquadFilter { |
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public: |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2 * exp(-M_LN10 / 20 * r); |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r * alpha; |
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d.b1 = 0.0; |
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d.b2 = a0r * -alpha; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Bandreject filter |
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* |
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* Bandreject filter based on biquad filter implementation. |
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*/ |
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class BandrejectFilter : public BiquadFilter { |
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public: |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2 * exp(-M_LN10 / 20 * r); |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r; |
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d.b1 = a0r * (-2.0 * cs); |
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d.b2 = a0r; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Highpass filter |
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* |
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* Highpass filter based on biquad filter implementation. |
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*/ |
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class HighpassFilter : public BiquadFilter { |
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public: |
342 |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2 * exp(-M_LN10 / 20 * r); |
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r * (1.0 + cs) * 0.5; |
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d.b1 = a0r * -(1.0 + cs); |
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d.b2 = a0r * (1.0 + cs) * 0.5; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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} |
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}; |
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/** @brief Four pole highpass filter |
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* |
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* Highpass filter based on three cascaded biquad filters. |
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*/ |
361 |
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class HighpassFilter4p : public DoubleBiquadFilter { |
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public: |
363 |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
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float omega = 2.0 * M_PI * fc / fs; |
365 |
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float sn = sin(omega); |
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float cs = cos(omega); |
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float alpha = sn * M_SQRT1_2; |
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|
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float a0r = 1.0 / (1.0 + alpha); |
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d.b0 = a0r * (1.0 + cs) * 0.5; |
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d.b1 = a0r * -(1.0 + cs); |
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d.b2 = a0r * (1.0 + cs) * 0.5; |
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d.a1 = a0r * (2.0 * cs); |
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d.a2 = a0r * (alpha - 1.0); |
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alpha *= exp(-M_LN10 / 20 * r); |
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a0r = 1.0 / (1.0 + alpha); |
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d.d2.b0 = a0r * (1.0 + cs) * 0.5; |
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d.d2.b1 = a0r * -(1.0 + cs); |
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d.d2.b2 = a0r * (1.0 + cs) * 0.5; |
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d.d2.a1 = a0r * (2.0 * cs); |
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d.d2.a2 = a0r * (alpha - 1.0); |
384 |
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} |
385 |
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}; |
386 |
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|
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/** @brief Six pole highpass filter |
388 |
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* |
389 |
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* Highpass filter based on three cascaded biquad filters. |
390 |
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*/ |
391 |
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class HighpassFilter6p : public TripleBiquadFilter { |
392 |
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public: |
393 |
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void SetParameters(FilterData& d, float fc, float r, float fs) const { |
394 |
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float omega = 2.0 * M_PI * fc / fs; |
395 |
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float sn = sin(omega); |
396 |
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float cs = cos(omega); |
397 |
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float alpha = sn * M_SQRT1_2; |
398 |
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|
399 |
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float a0r = 1.0 / (1.0 + alpha); |
400 |
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d.b0 = d.d2.b0 = a0r * (1.0 + cs) * 0.5; |
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d.b1 = d.d2.b1 = a0r * -(1.0 + cs); |
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d.b2 = d.d2.b2 = a0r * (1.0 + cs) * 0.5; |
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d.a1 = d.d2.a1 = a0r * (2.0 * cs); |
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d.a2 = d.d2.a2 = a0r * (alpha - 1.0); |
405 |
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|
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alpha *= exp(-M_LN10 / 20 * r); |
407 |
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a0r = 1.0 / (1.0 + alpha); |
408 |
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|
409 |
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d.d3.b0 = a0r * (1.0 + cs) * 0.5; |
410 |
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d.d3.b1 = a0r * -(1.0 + cs); |
411 |
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d.d3.b2 = a0r * (1.0 + cs) * 0.5; |
412 |
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d.d3.a1 = a0r * (2.0 * cs); |
413 |
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d.d3.a2 = a0r * (alpha - 1.0); |
414 |
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} |
415 |
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}; |
416 |
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|
417 |
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namespace gig { |
418 |
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|
419 |
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/** |
420 |
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* Base class for the gig engine filters. |
421 |
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*/ |
422 |
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class GigFilter : public FilterBase { |
423 |
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public: |
424 |
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void Reset(FilterData& d) const { |
425 |
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d.x1 = d.x2 = d.x3 = 0; |
426 |
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d.y1 = d.y2 = d.y3 = 0; |
427 |
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} |
428 |
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protected: |
429 |
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float ApplyA(FilterData& d, float x) const { |
430 |
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float y = x - d.a1 * d.y1 - d.a2 * d.y2 - d.a3 * d.y3; |
431 |
|
KillDenormal(y); |
432 |
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d.y3 = d.y2; |
433 |
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d.y2 = d.y1; |
434 |
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d.y1 = y; |
435 |
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return y; |
436 |
|
} |
437 |
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}; |
438 |
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|
439 |
|
#define GIG_PARAM_INIT \ |
440 |
|
float f1 = fc * 0.0075279; \ |
441 |
|
float f2 = f1 - 1 + r * fc * (-5.5389e-5 + 1.1982e-7 * fc); \ |
442 |
|
float scale = r < 51 ? 1.0f : 1.3762f - 0.0075073f * r |
443 |
|
|
444 |
|
class LowpassFilter : public GigFilter { |
445 |
|
public: |
446 |
|
float Apply(FilterData& d, float x) const { |
447 |
|
return ApplyA(d, d.b0 * x); |
448 |
|
} |
449 |
|
|
450 |
|
void SetParameters(FilterData& d, float fc, float r, float fs) const { |
451 |
|
GIG_PARAM_INIT; |
452 |
|
|
453 |
|
float f1_2 = f1 * f1; |
454 |
|
d.b0 = f1_2 * scale; |
455 |
|
d.a1 = f2; |
456 |
|
d.a2 = f1_2 - 1; |
457 |
|
d.a3 = -f2; |
458 |
|
} |
459 |
|
}; |
460 |
|
|
461 |
|
class BandpassFilter : public GigFilter { |
462 |
|
public: |
463 |
|
float Apply(FilterData& d, float x) const { |
464 |
|
float y = ApplyA(d, d.b0 * x + d.b2 * d.x2); |
465 |
|
d.x2 = d.x1; |
466 |
|
d.x1 = x; |
467 |
|
return y; |
468 |
|
} |
469 |
|
|
470 |
|
void SetParameters(FilterData& d, float fc, float r, float fs) const { |
471 |
|
GIG_PARAM_INIT; |
472 |
|
|
473 |
|
d.b0 = f1 * scale; |
474 |
|
d.b2 = -d.b0; |
475 |
|
d.a1 = f2; |
476 |
|
d.a2 = f1 * f1 - 1; |
477 |
|
d.a3 = -f2; |
478 |
|
} |
479 |
|
}; |
480 |
|
|
481 |
|
class HighpassFilter : public GigFilter { |
482 |
|
float Apply(FilterData& d, float x) const { |
483 |
|
float y = ApplyA(d, -x + d.x1 + d.x2 - d.x3); |
484 |
|
d.x3 = d.x2; |
485 |
|
d.x2 = d.x1; |
486 |
|
d.x1 = x; |
487 |
|
return y * d.scale; |
488 |
|
} |
489 |
|
|
490 |
|
void SetParameters(FilterData& d, float fc, float r, float fs) const { |
491 |
|
GIG_PARAM_INIT; |
492 |
|
|
493 |
|
d.a1 = f2; |
494 |
|
d.a2 = f1 * f1 - 1; |
495 |
|
d.a3 = -f2; |
496 |
|
d.scale = scale; |
497 |
|
} |
498 |
|
}; |
499 |
|
|
500 |
|
class BandrejectFilter : public GigFilter { |
501 |
|
float Apply(FilterData& d, float x) const { |
502 |
|
float y = ApplyA(d, x - d.x1 + d.b2 * d.x2 + d.x3); |
503 |
|
d.x3 = d.x2; |
504 |
|
d.x2 = d.x1; |
505 |
|
d.x1 = x; |
506 |
|
return y * d.scale; |
507 |
|
} |
508 |
|
|
509 |
|
void SetParameters(FilterData& d, float fc, float r, float fs) const { |
510 |
|
GIG_PARAM_INIT; |
511 |
|
|
512 |
|
d.b2 = f1 * f1 - 1; |
513 |
|
d.a1 = f2; |
514 |
|
d.a2 = d.b2; |
515 |
|
d.a3 = -f2; |
516 |
|
d.scale = scale; |
517 |
|
} |
518 |
|
}; |
519 |
|
|
520 |
|
class LowpassTurboFilter : public LowpassFilter { |
521 |
|
public: |
522 |
|
float Apply(FilterData& d, float x) const { |
523 |
|
float y = d.b20 * LowpassFilter::Apply(d, x) |
524 |
|
- d.a1 * d.y21 - d.a2 * d.y22 - d.a3 * d.y23; |
525 |
|
KillDenormal(y); |
526 |
|
d.y23 = d.y22; |
527 |
|
d.y22 = d.y21; |
528 |
|
d.y21 = y; |
529 |
|
return y; |
530 |
|
} |
531 |
|
|
532 |
|
void SetParameters(FilterData& d, float fc, float r, float fs) const { |
533 |
|
LowpassFilter::SetParameters(d, fc, r, fs); |
534 |
|
d.b20 = d.b0 * 0.5; |
535 |
|
} |
536 |
|
}; |
537 |
|
} //namespace gig |
538 |
|
|
539 |
|
|
540 |
|
/** |
541 |
|
* Main filter class. |
542 |
*/ |
*/ |
543 |
class Filter { |
class Filter { |
544 |
protected: |
protected: |
545 |
BandpassFilter BasicBPFilter; |
static const LowpassFilter1p lp1p; |
546 |
HighpassFilter HPFilter; |
static const LowpassFilter lp2p; |
547 |
BandpassFilter BPFilter; |
static const LowpassFilter4p lp4p; |
548 |
LowpassFilter LPFilter; |
static const LowpassFilter6p lp6p; |
549 |
BiquadFilter* pFilter; |
static const BandpassFilter bp2p; |
550 |
bq_t scale; |
static const BandrejectFilter br2p; |
551 |
bq_t resonance; |
static const HighpassFilter1p hp1p; |
552 |
bq_t cutoff; |
static const HighpassFilter hp2p; |
553 |
::gig::vcf_type_t Type; |
static const HighpassFilter4p hp4p; |
554 |
static const float fFB = LSF_FB; |
static const HighpassFilter6p hp6p; |
555 |
public: |
/** |
556 |
|
* These are filters similar to the ones from Gigasampler. |
557 |
|
*/ |
558 |
|
static const gig::HighpassFilter HPFilter; |
559 |
|
static const gig::BandpassFilter BPFilter; |
560 |
|
static const gig::LowpassFilter LPFilter; |
561 |
|
static const gig::BandrejectFilter BRFilter; |
562 |
|
static const gig::LowpassTurboFilter LPTFilter; |
563 |
|
|
564 |
|
FilterData d; |
565 |
|
const FilterBase* pFilter; |
566 |
|
|
567 |
|
public: |
568 |
Filter() { |
Filter() { |
569 |
// set filter type to 'lowpass' by default |
// set filter type to 'lowpass' by default |
570 |
pFilter = &LPFilter; |
pFilter = &LPFilter; |
571 |
Type = ::gig::vcf_type_lowpass; |
pFilter->Reset(d); |
572 |
} |
} |
573 |
|
|
574 |
inline bq_t Cutoff() { return cutoff; } |
enum vcf_type_t { |
575 |
|
vcf_type_gig_lowpass = ::gig::vcf_type_lowpass, |
576 |
inline bq_t Resonance() { return resonance; } |
vcf_type_gig_lowpassturbo = ::gig::vcf_type_lowpassturbo, |
577 |
|
vcf_type_gig_bandpass = ::gig::vcf_type_bandpass, |
578 |
|
vcf_type_gig_highpass = ::gig::vcf_type_highpass, |
579 |
|
vcf_type_gig_bandreject = ::gig::vcf_type_bandreject, |
580 |
|
vcf_type_1p_lowpass, |
581 |
|
vcf_type_1p_highpass, |
582 |
|
vcf_type_2p_lowpass, |
583 |
|
vcf_type_2p_highpass, |
584 |
|
vcf_type_2p_bandpass, |
585 |
|
vcf_type_2p_bandreject, |
586 |
|
vcf_type_4p_lowpass, |
587 |
|
vcf_type_4p_highpass, |
588 |
|
vcf_type_6p_lowpass, |
589 |
|
vcf_type_6p_highpass |
590 |
|
}; |
591 |
|
|
592 |
inline void SetType(::gig::vcf_type_t FilterType) { |
void SetType(vcf_type_t FilterType) { |
593 |
switch (FilterType) { |
switch (FilterType) { |
594 |
case ::gig::vcf_type_highpass: |
case vcf_type_gig_highpass: |
595 |
pFilter = &HPFilter; |
pFilter = &HPFilter; |
596 |
break; |
break; |
597 |
case ::gig::vcf_type_bandreject: //TODO: not implemented yet |
case vcf_type_gig_bandreject: |
598 |
Type = ::gig::vcf_type_bandpass; |
pFilter = &BRFilter; |
599 |
case ::gig::vcf_type_bandpass: |
break; |
600 |
|
case vcf_type_gig_bandpass: |
601 |
pFilter = &BPFilter; |
pFilter = &BPFilter; |
602 |
break; |
break; |
603 |
case ::gig::vcf_type_lowpassturbo: //TODO: not implemented yet |
case vcf_type_gig_lowpassturbo: |
604 |
default: |
pFilter = &LPTFilter; |
|
Type = ::gig::vcf_type_lowpass; |
|
|
case ::gig::vcf_type_lowpass: |
|
|
pFilter = &LPFilter; |
|
|
|
|
|
} |
|
|
Type = FilterType; |
|
|
} |
|
|
|
|
|
inline void SetParameters(bq_t cutoff, bq_t resonance, bq_t fs) { |
|
|
BasicBPFilter.SetParameters(cutoff, 0.7, fs); |
|
|
switch (Type) { |
|
|
case ::gig::vcf_type_highpass: |
|
|
HPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
|
605 |
break; |
break; |
606 |
case ::gig::vcf_type_bandpass: |
case vcf_type_1p_lowpass: |
607 |
BPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
pFilter = &lp1p; |
608 |
break; |
break; |
609 |
case ::gig::vcf_type_lowpass: |
case vcf_type_1p_highpass: |
610 |
LPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
pFilter = &hp1p; |
611 |
break; |
break; |
612 |
} |
case vcf_type_2p_lowpass: |
613 |
this->scale = 1.0f - resonance * 0.7f; |
pFilter = &lp2p; |
|
this->resonance = resonance; |
|
|
this->cutoff = cutoff; |
|
|
} |
|
|
|
|
|
inline void SetParameters(biquad_param_t* base, biquad_param_t* main, bq_t cutoff, bq_t resonance, bq_t fs) { |
|
|
BasicBPFilter.SetParameters(base, cutoff, 0.7, fs); |
|
|
switch (Type) { |
|
|
case ::gig::vcf_type_highpass: |
|
|
HPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs); |
|
614 |
break; |
break; |
615 |
case ::gig::vcf_type_bandpass: |
case vcf_type_2p_highpass: |
616 |
BPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs); |
pFilter = &hp2p; |
617 |
break; |
break; |
618 |
case ::gig::vcf_type_lowpass: |
case vcf_type_2p_bandpass: |
619 |
LPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs); |
pFilter = &bp2p; |
620 |
break; |
break; |
621 |
|
case vcf_type_2p_bandreject: |
622 |
|
pFilter = &br2p; |
623 |
|
break; |
624 |
|
case vcf_type_4p_lowpass: |
625 |
|
pFilter = &lp4p; |
626 |
|
break; |
627 |
|
case vcf_type_4p_highpass: |
628 |
|
pFilter = &hp4p; |
629 |
|
break; |
630 |
|
case vcf_type_6p_lowpass: |
631 |
|
pFilter = &lp6p; |
632 |
|
break; |
633 |
|
case vcf_type_6p_highpass: |
634 |
|
pFilter = &hp6p; |
635 |
|
break; |
636 |
|
default: |
637 |
|
pFilter = &LPFilter; |
638 |
} |
} |
639 |
this->scale = 1.0f - resonance * 0.7f; |
pFilter->Reset(d); |
|
this->resonance = resonance; |
|
|
this->cutoff = cutoff; |
|
|
} |
|
|
|
|
|
void Reset() { |
|
|
BasicBPFilter.Reset(); |
|
|
HPFilter.Reset(); |
|
|
BPFilter.Reset(); |
|
|
LPFilter.Reset(); |
|
640 |
} |
} |
641 |
|
|
642 |
inline bq_t Apply(const bq_t in) { |
void SetParameters(float cutoff, float resonance, float fs) { |
643 |
return pFilter->Apply(in) * this->scale + |
pFilter->SetParameters(d, cutoff, resonance, fs); |
|
BasicBPFilter.ApplyFB(in, this->resonance * LSF_FB) * this->resonance; |
|
644 |
} |
} |
645 |
|
|
646 |
inline bq_t Apply(biquad_param_t* base, biquad_param_t* main, const bq_t in) { |
void Reset() { |
647 |
return pFilter->Apply(main, in) * this->scale + |
return pFilter->Reset(d); |
|
BasicBPFilter.ApplyFB(base, in, this->resonance * LSF_FB) * this->resonance; |
|
648 |
} |
} |
649 |
|
|
650 |
#if ARCH_X86 |
float Apply(float in) { |
651 |
// expects to find input in xmm0 and leaves output in xmm7 |
return pFilter->Apply(d, in); |
|
inline void Apply4StepsSSE(biquad_param_t* base, biquad_param_t* main) { |
|
|
float fb; |
|
|
__asm__ __volatile__ ( |
|
|
"movss %0, %%xmm4\n\t" |
|
|
"mulss %1, %%xmm4 # this->resonance * LSF_FB\n\t" |
|
|
"movss %%xmm4, %2\n\t" |
|
|
:: "m" (fFB), /* %0 */ |
|
|
"m" (resonance), /* %1 */ |
|
|
"m" (fb) /* %2 */ |
|
|
); |
|
|
BasicBPFilter.ApplyFB4StepsSSE(base, fb); // leaves output in xmm7 |
|
|
__asm__ __volatile__ ( |
|
|
"movss %0, %%xmm4\n\t" |
|
|
"shufps $0, %%xmm4, %%xmm4 # copy to other 3 cells\n\t" |
|
|
"mulps %%xmm4, %%xmm7 # ApplyFB() * this->resonance\n\t" |
|
|
:: "m" (resonance) /* %0 */ |
|
|
); |
|
|
pFilter->Apply4StepsSSE(main); // leaves output in xmm6 |
|
|
__asm__ __volatile__ ( |
|
|
"movss %0, %%xmm5\n\t" |
|
|
"shufps $0, %%xmm5, %%xmm5 # copy to other 3 cells\n\t" |
|
|
"mulps %%xmm5, %%xmm6 # Apply() * this->scale\n\t" |
|
|
"addps %%xmm6, %%xmm7 # xmm7 = result\n\t" |
|
|
:: "m" (scale) /* %0 */ |
|
|
); |
|
652 |
} |
} |
|
#endif // ARCH_X86 |
|
|
|
|
653 |
}; |
}; |
654 |
|
|
655 |
}} //namespace LinuxSampler::gig |
} //namespace LinuxSampler |
656 |
|
|
657 |
#endif // __LS_GIG_FILTER_H__ |
#endif // __LS_GIG_FILTER_H__ |