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/*************************************************************************** |
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* * |
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* LinuxSampler - modular, streaming capable sampler * |
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* * |
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* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck * |
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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., 59 Temple Place, Suite 330, Boston, * |
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* MA 02111-1307 USA * |
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***************************************************************************/ |
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|
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#ifndef __LS_GIG_FILTER_H__ |
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#define __LS_GIG_FILTER_H__ |
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|
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#include "../../common/global.h" |
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|
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#if DEBUG_HEADERS |
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# warning Filter.h included |
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#endif // DEBUG_HEADERS |
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|
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#include "../common/BiquadFilter.h" |
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|
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// TODO: Gigasampler's "Turbo Lowpass" and "Bandreject" filters not implemented yet |
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|
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#include "../../lib/fileloader/libgig/gig.h" |
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|
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#define LSF_BW 0.9 |
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#define LSF_FB 0.9f |
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|
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namespace LinuxSampler { namespace gig { |
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|
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/** |
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* This is a filter similar to the ones from Gigasampler. |
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*/ |
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class Filter { |
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protected: |
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BandpassFilter BasicBPFilter; |
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HighpassFilter HPFilter; |
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BandpassFilter BPFilter; |
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LowpassFilter LPFilter; |
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BiquadFilter* pFilter; |
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bq_t scale; |
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bq_t resonance; |
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bq_t cutoff; |
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::gig::vcf_type_t Type; |
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public: |
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bool Enabled; |
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|
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inline Filter() { |
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// set filter type to 'lowpass' by default |
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pFilter = &LPFilter; |
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Type = ::gig::vcf_type_lowpass; |
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} |
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|
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inline bq_t Cutoff() { return cutoff; } |
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|
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inline bq_t Resonance() { return resonance; } |
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|
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inline void SetType(::gig::vcf_type_t FilterType) { |
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switch (FilterType) { |
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case ::gig::vcf_type_highpass: |
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pFilter = &HPFilter; |
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break; |
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case ::gig::vcf_type_bandreject: //TODO: not implemented yet |
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Type = ::gig::vcf_type_bandpass; |
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case ::gig::vcf_type_bandpass: |
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pFilter = &BPFilter; |
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break; |
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case ::gig::vcf_type_lowpassturbo: //TODO: not implemented yet |
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default: |
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Type = ::gig::vcf_type_lowpass; |
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case ::gig::vcf_type_lowpass: |
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pFilter = &LPFilter; |
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|
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} |
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Type = FilterType; |
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} |
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|
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inline void SetParameters(bq_t cutoff, bq_t resonance, bq_t fs) { |
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BasicBPFilter.SetParameters(cutoff, 0.7, fs); |
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switch (Type) { |
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case ::gig::vcf_type_highpass: |
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HPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
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break; |
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case ::gig::vcf_type_bandpass: |
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BPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
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break; |
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case ::gig::vcf_type_lowpass: |
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LPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs); |
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break; |
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} |
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this->scale = 1.0f - resonance * 0.7f; |
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this->resonance = resonance; |
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this->cutoff = cutoff; |
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} |
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|
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inline bq_t Apply(const bq_t in) { |
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return (Enabled) ? pFilter->Apply(in) * this->scale + |
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BasicBPFilter.ApplyFB(in, this->resonance * LSF_FB) * this->resonance |
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: in; |
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} |
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}; |
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|
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}} //namespace LinuxSampler::gig |
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|
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#endif // __LS_GIG_FILTER_H__ |