engines/gig/Filter.h

/***************************************************************************
 *                                                                         *
 *   LinuxSampler - modular, streaming capable sampler                     *
 *                                                                         *
 *   Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck   *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program; if not, write to the Free Software           *
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston,                 *
 *   MA  02111-1307  USA                                                   *
 ***************************************************************************/

#ifndef __LS_GIG_FILTER_H__
#define __LS_GIG_FILTER_H__

#include "../../common/global.h"

#if DEBUG_HEADERS
# warning Filter.h included
#endif // DEBUG_HEADERS

#include "../common/BiquadFilter.h"

// TODO: Gigasampler's "Turbo Lowpass" and "Bandreject" filters not implemented yet

#include "../../lib/fileloader/libgig/gig.h"

#define LSF_BW 0.9
#define LSF_FB 0.9f

namespace LinuxSampler { namespace gig {

    /**
     * These are filters similar to the ones from Gigasampler.
     */
    class Filter {
        protected:
            BandpassFilter    BasicBPFilter;
            HighpassFilter    HPFilter;
            BandpassFilter    BPFilter;
            LowpassFilter     LPFilter;
            BiquadFilter*     pFilter;
            bq_t              scale;
            bq_t              resonance;
            bq_t              cutoff;
            ::gig::vcf_type_t Type;
        public:
            bool Enabled;

            inline Filter() {
                // set filter type to 'lowpass' by default
                pFilter = &LPFilter;
                Type    = ::gig::vcf_type_lowpass;
            }

            inline bq_t Cutoff()     { return cutoff; }

            inline bq_t Resonance()  { return resonance; }

            inline void SetType(::gig::vcf_type_t FilterType) {
                switch (FilterType) {
                    case ::gig::vcf_type_highpass:
                        pFilter = &HPFilter;
                        break;
                    case ::gig::vcf_type_bandreject: //TODO: not implemented yet
                        Type = ::gig::vcf_type_bandpass;
                    case ::gig::vcf_type_bandpass:
                        pFilter = &BPFilter;
                        break;
                    case ::gig::vcf_type_lowpassturbo: //TODO: not implemented yet
                    default:
                        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);
                        break;
                    case ::gig::vcf_type_bandpass:
                        BPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs);
                        break;
                    case ::gig::vcf_type_lowpass:
                        LPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs);
                        break;
                }
                this->scale     = 1.0f - resonance * 0.7f;
                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);
                        break;
                    case ::gig::vcf_type_bandpass:
                        BPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs);
                        break;
                    case ::gig::vcf_type_lowpass:
                        LPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs);
                        break;
                }
                this->scale     = 1.0f - resonance * 0.7f;
                this->resonance = resonance;
                this->cutoff    = cutoff;
            }

            inline bq_t Apply(const bq_t in) {
                return (Enabled) ? pFilter->Apply(in) * this->scale +
                                  BasicBPFilter.ApplyFB(in, this->resonance * LSF_FB) * this->resonance
                                : in;
            }

            inline bq_t Apply(biquad_param_t* base, biquad_param_t* main, const bq_t in) {
                return (Enabled) ? pFilter->Apply(main, in) * this->scale +
                                  BasicBPFilter.ApplyFB(base, in, this->resonance * LSF_FB) * this->resonance
                                : in;
            }
    };

}} //namespace LinuxSampler::gig

#endif // __LS_GIG_FILTER_H__
1	schoenebeck	53	/***************************************************************************
2			* *
3			* LinuxSampler - modular, streaming capable sampler *
4			* *
5	schoenebeck	56	* Copyright (C) 2003, 2004 by Benno Senoner and Christian Schoenebeck *
6	schoenebeck	53	* *
7			* This program is free software; you can redistribute it and/or modify *
8			* it under the terms of the GNU General Public License as published by *
9			* the Free Software Foundation; either version 2 of the License, or *
10			* (at your option) any later version. *
11			* *
12			* This program is distributed in the hope that it will be useful, *
13			* but WITHOUT ANY WARRANTY; without even the implied warranty of *
14			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
15			* GNU General Public License for more details. *
16			* *
17			* You should have received a copy of the GNU General Public License *
18			* along with this program; if not, write to the Free Software *
19			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, *
20			* MA 02111-1307 USA *
21			***************************************************************************/
22
23			#ifndef __LS_GIG_FILTER_H__
24			#define __LS_GIG_FILTER_H__
25
26			#include "../../common/global.h"
27
28			#if DEBUG_HEADERS
29			# warning Filter.h included
30			#endif // DEBUG_HEADERS
31
32			#include "../common/BiquadFilter.h"
33
34			// TODO: Gigasampler's "Turbo Lowpass" and "Bandreject" filters not implemented yet
35
36			#include "../../lib/fileloader/libgig/gig.h"
37
38			#define LSF_BW 0.9
39			#define LSF_FB 0.9f
40
41			namespace LinuxSampler { namespace gig {
42
43			/**
44	schoenebeck	80	* These are filters similar to the ones from Gigasampler.
45	schoenebeck	53	*/
46			class Filter {
47			protected:
48			BandpassFilter BasicBPFilter;
49			HighpassFilter HPFilter;
50			BandpassFilter BPFilter;
51			LowpassFilter LPFilter;
52			BiquadFilter* pFilter;
53			bq_t scale;
54			bq_t resonance;
55			bq_t cutoff;
56			::gig::vcf_type_t Type;
57			public:
58			bool Enabled;
59
60			inline Filter() {
61			// set filter type to 'lowpass' by default
62			pFilter = &LPFilter;
63			Type = ::gig::vcf_type_lowpass;
64			}
65
66			inline bq_t Cutoff() { return cutoff; }
67
68			inline bq_t Resonance() { return resonance; }
69
70			inline void SetType(::gig::vcf_type_t FilterType) {
71			switch (FilterType) {
72			case ::gig::vcf_type_highpass:
73			pFilter = &HPFilter;
74			break;
75			case ::gig::vcf_type_bandreject: //TODO: not implemented yet
76			Type = ::gig::vcf_type_bandpass;
77			case ::gig::vcf_type_bandpass:
78			pFilter = &BPFilter;
79			break;
80			case ::gig::vcf_type_lowpassturbo: //TODO: not implemented yet
81			default:
82			Type = ::gig::vcf_type_lowpass;
83			case ::gig::vcf_type_lowpass:
84			pFilter = &LPFilter;
85
86			}
87			Type = FilterType;
88			}
89
90			inline void SetParameters(bq_t cutoff, bq_t resonance, bq_t fs) {
91			BasicBPFilter.SetParameters(cutoff, 0.7, fs);
92			switch (Type) {
93			case ::gig::vcf_type_highpass:
94			HPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs);
95			break;
96			case ::gig::vcf_type_bandpass:
97			BPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs);
98			break;
99			case ::gig::vcf_type_lowpass:
100			LPFilter.SetParameters(cutoff, 1.0 - resonance * LSF_BW, fs);
101			break;
102			}
103			this->scale = 1.0f - resonance * 0.7f;
104			this->resonance = resonance;
105			this->cutoff = cutoff;
106			}
107
108	schoenebeck	80	inline void SetParameters(biquad_param_t* base, biquad_param_t* main, bq_t cutoff, bq_t resonance, bq_t fs) {
109			BasicBPFilter.SetParameters(base, cutoff, 0.7, fs);
110			switch (Type) {
111			case ::gig::vcf_type_highpass:
112			HPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs);
113			break;
114			case ::gig::vcf_type_bandpass:
115			BPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs);
116			break;
117			case ::gig::vcf_type_lowpass:
118			LPFilter.SetParameters(main, cutoff, 1.0 - resonance * LSF_BW, fs);
119			break;
120			}
121			this->scale = 1.0f - resonance * 0.7f;
122			this->resonance = resonance;
123			this->cutoff = cutoff;
124			}
125
126	schoenebeck	53	inline bq_t Apply(const bq_t in) {
127			return (Enabled) ? pFilter->Apply(in) * this->scale +
128			BasicBPFilter.ApplyFB(in, this->resonance * LSF_FB) * this->resonance
129			: in;
130			}
131	schoenebeck	80
132			inline bq_t Apply(biquad_param_t* base, biquad_param_t* main, const bq_t in) {
133			return (Enabled) ? pFilter->Apply(main, in) * this->scale +
134			BasicBPFilter.ApplyFB(base, in, this->resonance * LSF_FB) * this->resonance
135			: in;
136			}
137	schoenebeck	53	};
138
139			}} //namespace LinuxSampler::gig
140
141			#endif // __LS_GIG_FILTER_H__