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authorPeter D'Hoye <peter.dhoye@gmail.com>2009-05-24 21:28:16 +0000
committerPeter D'Hoye <peter.dhoye@gmail.com>2009-05-24 21:28:16 +0000
commit526b5580dabbfed7cfe5439dc3a90ec727f563c2 (patch)
tree22b1af92348785daad16714ee5e2b633017e0e48 /apps/plugins/pdbox/PDa/extra/equalizer.c
parent4f2dfcc01b260d946044ef2b6af5fe36cb772c8d (diff)
downloadrockbox-526b5580dabbfed7cfe5439dc3a90ec727f563c2.tar.gz
rockbox-526b5580dabbfed7cfe5439dc3a90ec727f563c2.zip
Cut the files in half and it might work better (note to self: check your tree is really clean before patching)
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21070 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/plugins/pdbox/PDa/extra/equalizer.c')
-rw-r--r--apps/plugins/pdbox/PDa/extra/equalizer.c94
1 files changed, 1 insertions, 93 deletions
diff --git a/apps/plugins/pdbox/PDa/extra/equalizer.c b/apps/plugins/pdbox/PDa/extra/equalizer.c
index 1d21c4087c..743832302b 100644
--- a/apps/plugins/pdbox/PDa/extra/equalizer.c
+++ b/apps/plugins/pdbox/PDa/extra/equalizer.c
@@ -83,96 +83,4 @@ void equalizer_setup(void)
83 class_addfloat(equ_class,equ_float); 83 class_addfloat(equ_class,equ_float);
84} 84}
85 85
86 86
87
88
89
90/* (C) Guenter Geiger <geiger@epy.co.at> */
91
92
93/*
94
95 These filter coefficients computations are taken from
96 http://www.harmony-central.com/Computer/Programming/Audio-EQ-Cookbook.txt
97
98 written by Robert Bristow-Johnson
99
100*/
101
102#include "m_pd.h"
103#ifdef NT
104#pragma warning( disable : 4244 )
105#pragma warning( disable : 4305 )
106#endif
107#include <math.h>
108#include "filters.h"
109
110
111
112/* ------------------- equ ----------------------------*/
113static t_class *equ_class;
114
115void equ_bang(t_rbjfilter *x)
116{
117 t_atom at[5];
118 t_float omega = e_omega(x->x_freq,x->x_rate);
119 t_float alpha = e_alpha(x->x_bw*0.01,omega);
120 t_float b0 = 1 + alpha*e_A(x->x_gain);
121 t_float b1 = -2.*cos(omega);
122 t_float b2 = 1 - alpha*e_A(x->x_gain);
123 t_float a0 = 1 + alpha/e_A(x->x_gain);
124 t_float a1 = -2.*cos(omega);
125 t_float a2 = 1 - alpha/e_A(x->x_gain);
126
127/* post("bang %f %f %f",x->x_freq, x->x_gain, x->x_bw);*/
128
129 if (!check_stability(-a1/a0,-a2/a0,b0/a0,b1/a0,b2/a0)) {
130 post("equ: filter unstable -> resetting");
131 a0=1.;a1=0.;a2=0.;
132 b0=1.;b1=0.;b2=0.;
133 }
134
135 SETFLOAT(at,-a1/a0);
136 SETFLOAT(at+1,-a2/a0);
137 SETFLOAT(at+2,b0/a0);
138 SETFLOAT(at+3,b1/a0);
139 SETFLOAT(at+4,b2/a0);
140
141 outlet_list(x->x_obj.ob_outlet,&s_list,5,at);
142}
143
144
145void equ_float(t_rbjfilter *x,t_floatarg f)
146{
147 x->x_freq = f;
148 equ_bang(x);
149}
150
151
152static void *equ_new(t_floatarg f,t_floatarg g,t_floatarg bw)
153{
154 t_rbjfilter *x = (t_rbjfilter *)pd_new(equ_class);
155
156 x->x_rate = 44100.0;
157 outlet_new(&x->x_obj,&s_float);
158 floatinlet_new(&x->x_obj, &x->x_gain);
159 floatinlet_new(&x->x_obj, &x->x_bw);
160 if (f > 0.) x->x_freq = f;
161 if (bw > 0.) x->x_bw = bw;
162 if (g != 0.) x->x_gain = g;
163 return (x);
164}
165
166
167void equalizer_setup(void)
168{
169 equ_class = class_new(gensym("equalizer"), (t_newmethod)equ_new, 0,
170 sizeof(t_rbjfilter), 0,A_DEFFLOAT,A_DEFFLOAT,A_DEFFLOAT,0);
171 class_addbang(equ_class,equ_bang);
172 class_addfloat(equ_class,equ_float);
173}
174
175
176
177
178