aboutsummaryrefslogtreecommitdiff
path: root/src/mtx_dispersive_dline.c
blob: 649ceab54f14122f33b8facead73c7544ea986d5 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
/******************************************************
 *
 * warped delay line
 *
 *   written by Franz Zotter
 *
 *   2007
 *
 *   institute of electronic music and acoustics (iem)
 *
 ******************************************************
 *
 * license: GNU General Public License v.2
 *
 ******************************************************/


/* ------------------------ mtx_dispersive_dline~ ----------------------------- */

/* builds a tap vector with first order all-passes A instead of unit delays.
 * 'ha *' denotes the convolution with the impulse response of A. The chain is of
 * length L
   {x[n]} -> {... ha * ha * x[n], ha * x[n], x[n]} 

   especially useful for frequency warped ffts

   All-pass z-Transform A(z)=(1+lambda*z)/(z-lambda), lambda ... input parameter
   
inlet:  is a signal matrix with C rows (number of channels) and N columns (samples)
outlet: C rows and L colums matrix with current state of the dispersive delay 
   line after computing the N imput samples. It is possible to capture 
   the list outlet every sample when using a column (sample) vector as input matrix.
 
   creation input parameters are:

1: L ...        length of allpass chain
2: lambda ...   alpass/warping parameter


*/

#include "iemmatrix.h"

static t_class *mtx_dispersive_dline_class;

typedef struct _mtx_dispersive_dline
{
  t_object x_obj;
  t_float lambda;
  int length;
  int channels;
  int size;
  t_float *z;
  t_float *tap;
  t_atom *list_out;
  t_outlet *list_outlet;
} t_mtx_dispersive_dline;

static void mtx_dispersive_dline_bang (t_mtx_dispersive_dline *x)
{
   int count;
   t_atom *list = x->list_out;
   SETFLOAT(list, (t_float) x->channels);
   SETFLOAT(list+1, (t_float) x->length);

   list+=2;
   for (count=0; count < x->size; count++)
      SETFLOAT(&list[count],x->tap[count]);
   outlet_anything (x->list_outlet, gensym("matrix"), x->size+2, x->list_out);

}

static void mtx_dispersive_dline_set_lambda(t_mtx_dispersive_dline *x, t_floatarg f)
{
  if ((f<1.0f)&&(f>-1.0f))
	  x->lambda = f;
  else
	  post("mtx_dispersive_dline: stable allpass coefficient must be -1<lambda<1");
}

static void mtx_dispersive_dline_reset(t_mtx_dispersive_dline *x)
{
   int count;
   for (count=0;count<x->size;count++) {
      x->tap[count]=0;
      x->z[count]=0;
   }
}

static void mtx_dispersive_dline_delete(t_mtx_dispersive_dline *x)
{
      if(x->list_out)freebytes(x->list_out, sizeof(t_atom)*(x->size+2));
      if(x->tap)freebytes(x->tap, sizeof(t_float)*x->size);
      if(x->z)freebytes(x->z, sizeof(t_float)*x->size);
      x->z=0;
      x->tap=0;
      x->list_out=0;
}


static void mtx_dispersive_dline_resize(t_mtx_dispersive_dline *x, t_symbol *s,
      int argc, t_atom *argv)
{
   int length=(int)atom_getfloat(argv);
   int channels=x->channels;
   int size=length*channels;

   if (argc>1) {
      channels=(int)atom_getfloat(argv+1);
      size=length*channels;
      if ((channels<1)||(channels>1000)) {
	 post("mtx_dispersive_dline: number of channels (input rows) must lie between 1 and 1000!");
	 return; 
      }
   }

   if ((length<1)||(length>10000)) {
	  post("mtx_dispersive_dline: length not between 1 and 10000!");
	  return;
   }
   if ((x->size!=size)) {
      mtx_dispersive_dline_delete(x);
      if(!(x->list_out=(t_atom*) getbytes(sizeof(t_atom)*(size+2)))) {
	 post("mtx_dispersive_dline: out of memory");
	 mtx_dispersive_dline_delete(x);
	 return;
      }
      if(!(x->tap=(t_float*) getbytes(sizeof(t_float)*size))) {
	 post("mtx_dispersive_dline: out of memory");
	 mtx_dispersive_dline_delete(x);
	 return;
      }
      if(!(x->z = (t_float*) getbytes(sizeof(t_float)*size))) {
	 post("mtx_dispersive_dline: out of memory");
	 mtx_dispersive_dline_delete(x);
	 return;
      }
      x->length=length;
      x->channels=channels;
      x->size=size;
   }
}

static void allpass_chain_cycle (t_float x, t_float *y, t_float *z, int n, t_float a) {
	t_float w, in;
        int c;
	in = y[0] = x;
        // z[0] unused here
	for (c=1; c<n; c++) {
		w  = in + a * z[c]; 
		in = y[c] = z[c] - a * w;
		z[c] = w;
	}
}

static void mtx_dispersive_dline_matrix(t_mtx_dispersive_dline *x, t_symbol *s,
      int argc, t_atom *argv)
{
  int channels=(int)atom_getfloat(argv);
  int samples=(int)atom_getfloat(argv+1);
  int c,n,n2;
  t_atom resize_msg[2];
  
  if (channels*samples>argc) {
     post("mtx_dispersive_dline: corrupt matrix passed");
     return;
  }
  post("%d samples, %d channels",samples,channels);

  SETFLOAT(resize_msg,(t_float)x->length);
  SETFLOAT(resize_msg+1,(t_float)channels);
  mtx_dispersive_dline_resize(x,gensym("resize"),2,resize_msg);

  post("%d new size",x->size);

  argv+=2;
  for (c=0, n2=0; c<x->size; c+=x->length) {
     for (n=0; n<samples; n++, n2++) {
         allpass_chain_cycle (atom_getfloat(argv+n2),x->tap+c,x->z+c,x->length,x->lambda); 
     }
  }

  mtx_dispersive_dline_bang(x);
}

static void mtx_dispersive_dline_helper(void)
{
  post("\n%c mtx_dispersive_dline~-object for warping a signal");
  post("'help' : view this\n"
       "signal~");
  post("outlet : signal~");
}

static void *mtx_dispersive_dline_new(t_symbol *s, int argc, t_atom *argv)
{
  t_mtx_dispersive_dline *x = (t_mtx_dispersive_dline *)pd_new(mtx_dispersive_dline_class);
  t_float length=1;
  t_float lambda=0;
  t_atom resize_msg[2];

  x->list_outlet = outlet_new(&x->x_obj, &s_list);

  switch ((argc>2)?2:argc)
  {
     case 2:
	lambda=atom_getfloat(argv+1);
     case 1:
	length=atom_getfloat(argv);
  }
   
  x->length=0;
  x->channels=0;
  x->size=0;
  x->z=0;
  x->tap=0;
  x->list_out=0;
  mtx_dispersive_dline_set_lambda (x,lambda);
  SETFLOAT(resize_msg,(t_float)length);
  SETFLOAT(resize_msg+1,(t_float)1);
  mtx_dispersive_dline_resize (x,gensym("resize"),2,resize_msg);
  mtx_dispersive_dline_reset (x);
  return (x);
}

void mtx_dispersive_dline_setup(void)
{
  mtx_dispersive_dline_class = class_new(
	gensym("mtx_dispersive_dline"), 
	(t_newmethod)mtx_dispersive_dline_new, 
	(t_method)mtx_dispersive_dline_delete,
	sizeof(t_mtx_dispersive_dline),
	CLASS_DEFAULT,
	A_GIMME,0);
  class_addmethod (mtx_dispersive_dline_class, (t_method) mtx_dispersive_dline_matrix, 
	gensym("matrix"),A_GIMME,0);
  class_addmethod (mtx_dispersive_dline_class, (t_method) mtx_dispersive_dline_reset, 
	gensym("reset"), 0); 
  class_addmethod (mtx_dispersive_dline_class, (t_method) mtx_dispersive_dline_resize, 
	gensym("resize"), A_GIMME,0); 
  class_addmethod (mtx_dispersive_dline_class, (t_method) mtx_dispersive_dline_set_lambda, 
	gensym("lambda"), A_DEFFLOAT,0); 
 
  class_addmethod(mtx_dispersive_dline_class, (t_method)mtx_dispersive_dline_helper, gensym("help"), 0);
}

void iemtx_dispersive_dline_setup(void)
{
    mtx_dispersive_dline_setup();
}