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author | Peter D'Hoye <peter.dhoye@gmail.com> | 2009-05-22 21:58:48 +0000 |
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committer | Peter D'Hoye <peter.dhoye@gmail.com> | 2009-05-22 21:58:48 +0000 |
commit | 513389b4c1bc8afe4b2dc9947c534bfeb105e3da (patch) | |
tree | 10e673b35651ac567fed2eda0c679c7ade64cbc6 /apps/plugins/pdbox/PDa/extra/equalizer.c | |
parent | 95fa7f6a2ef466444fbe3fe87efc6d5db6b77b36 (diff) | |
download | rockbox-513389b4c1bc8afe4b2dc9947c534bfeb105e3da.tar.gz rockbox-513389b4c1bc8afe4b2dc9947c534bfeb105e3da.zip |
Add FS #10214. Initial commit of the original PDa code for the GSoC Pure Data plugin project of Wincent Balin. Stripped some non-sourcefiles and added a rockbox readme that needs a bit more info from Wincent. Is added to CATEGORIES and viewers, but not yet to SUBDIRS (ie doesn't build yet)
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21044 a1c6a512-1295-4272-9138-f99709370657
Diffstat (limited to 'apps/plugins/pdbox/PDa/extra/equalizer.c')
-rw-r--r-- | apps/plugins/pdbox/PDa/extra/equalizer.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/apps/plugins/pdbox/PDa/extra/equalizer.c b/apps/plugins/pdbox/PDa/extra/equalizer.c new file mode 100644 index 0000000000..1d21c4087c --- /dev/null +++ b/apps/plugins/pdbox/PDa/extra/equalizer.c | |||
@@ -0,0 +1,178 @@ | |||
1 | /* (C) Guenter Geiger <geiger@epy.co.at> */ | ||
2 | |||
3 | |||
4 | /* | ||
5 | |||
6 | These filter coefficients computations are taken from | ||
7 | http://www.harmony-central.com/Computer/Programming/Audio-EQ-Cookbook.txt | ||
8 | |||
9 | written by Robert Bristow-Johnson | ||
10 | |||
11 | */ | ||
12 | |||
13 | #include "m_pd.h" | ||
14 | #ifdef NT | ||
15 | #pragma warning( disable : 4244 ) | ||
16 | #pragma warning( disable : 4305 ) | ||
17 | #endif | ||
18 | #include <math.h> | ||
19 | #include "filters.h" | ||
20 | |||
21 | |||
22 | |||
23 | /* ------------------- equ ----------------------------*/ | ||
24 | static t_class *equ_class; | ||
25 | |||
26 | void equ_bang(t_rbjfilter *x) | ||
27 | { | ||
28 | t_atom at[5]; | ||
29 | t_float omega = e_omega(x->x_freq,x->x_rate); | ||
30 | t_float alpha = e_alpha(x->x_bw*0.01,omega); | ||
31 | t_float b0 = 1 + alpha*e_A(x->x_gain); | ||
32 | t_float b1 = -2.*cos(omega); | ||
33 | t_float b2 = 1 - alpha*e_A(x->x_gain); | ||
34 | t_float a0 = 1 + alpha/e_A(x->x_gain); | ||
35 | t_float a1 = -2.*cos(omega); | ||
36 | t_float a2 = 1 - alpha/e_A(x->x_gain); | ||
37 | |||
38 | /* post("bang %f %f %f",x->x_freq, x->x_gain, x->x_bw);*/ | ||
39 | |||
40 | if (!check_stability(-a1/a0,-a2/a0,b0/a0,b1/a0,b2/a0)) { | ||
41 | post("equ: filter unstable -> resetting"); | ||
42 | a0=1.;a1=0.;a2=0.; | ||
43 | b0=1.;b1=0.;b2=0.; | ||
44 | } | ||
45 | |||
46 | SETFLOAT(at,-a1/a0); | ||
47 | SETFLOAT(at+1,-a2/a0); | ||
48 | SETFLOAT(at+2,b0/a0); | ||
49 | SETFLOAT(at+3,b1/a0); | ||
50 | SETFLOAT(at+4,b2/a0); | ||
51 | |||
52 | outlet_list(x->x_obj.ob_outlet,&s_list,5,at); | ||
53 | } | ||
54 | |||
55 | |||
56 | void equ_float(t_rbjfilter *x,t_floatarg f) | ||
57 | { | ||
58 | x->x_freq = f; | ||
59 | equ_bang(x); | ||
60 | } | ||
61 | |||
62 | |||
63 | static void *equ_new(t_floatarg f,t_floatarg g,t_floatarg bw) | ||
64 | { | ||
65 | t_rbjfilter *x = (t_rbjfilter *)pd_new(equ_class); | ||
66 | |||
67 | x->x_rate = 44100.0; | ||
68 | outlet_new(&x->x_obj,&s_float); | ||
69 | floatinlet_new(&x->x_obj, &x->x_gain); | ||
70 | floatinlet_new(&x->x_obj, &x->x_bw); | ||
71 | if (f > 0.) x->x_freq = f; | ||
72 | if (bw > 0.) x->x_bw = bw; | ||
73 | if (g != 0.) x->x_gain = g; | ||
74 | return (x); | ||
75 | } | ||
76 | |||
77 | |||
78 | void equalizer_setup(void) | ||
79 | { | ||
80 | equ_class = class_new(gensym("equalizer"), (t_newmethod)equ_new, 0, | ||
81 | sizeof(t_rbjfilter), 0,A_DEFFLOAT,A_DEFFLOAT,A_DEFFLOAT,0); | ||
82 | class_addbang(equ_class,equ_bang); | ||
83 | class_addfloat(equ_class,equ_float); | ||
84 | } | ||
85 | |||
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 ----------------------------*/ | ||
113 | static t_class *equ_class; | ||
114 | |||
115 | void 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 | |||
145 | void equ_float(t_rbjfilter *x,t_floatarg f) | ||
146 | { | ||
147 | x->x_freq = f; | ||
148 | equ_bang(x); | ||
149 | } | ||
150 | |||
151 | |||
152 | static 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 | |||
167 | void 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 | |||