vg_audio_synth_bird.h

   1 #ifndef VG_AUDIO_SYNTH_BIRD_H
   2 #define VG_AUDIO_SYNTH_BIRD_H
   3
   4 #include "vg_binstr.h"
   5 #include "vg_stdint.h"
   6
   7 #ifndef BIRD_SAMPLE_RATE
   8  #define BIRD_SAMPLE_RATE 44100
   9 #endif
  10
  11 struct synth_bird_signature{
  12    float length, pause,  /* timings in seconds */
  13          x0,x1,x2,x3,    /* polynomial coefficients for the fundemental */
  14          v0,v1,v2,v3;    /* volume of each oscillator */
  15
  16    int   lfo_hz;         /* LFO frequency (30-60hz) */
  17    float fm;             /* LFO modulation depth (+/- hz) */
  18 };
  19
  20 struct synth_bird{
  21    struct{
  22       int osc_main[4],
  23           osc_lfo;
  24       float volume[4];
  25
  26       float fundamental;
  27       int x, length,       /* position/length of signature in samples */
  28           gate, adsr,      /* adsr ranges 0->44100 */
  29           frame;           /* current frame of the pattern */
  30
  31       int   lfo_hz;
  32       float fm_depth;
  33
  34       int adsr_rise,
  35           adsr_fall;
  36    }
  37    rt;
  38
  39    struct synth_bird_settings{
  40       int tones[4][2];        /* fraction of the fundemental tone
  41                                  for each oscillator */
  42       float adsr_rise,        /* rise/fall in seconds */
  43             adsr_fall;
  44
  45       enum bird_lfo_wave{
  46          k_bird_lfo_sine_approx,
  47          k_bird_lfo_bipolar_poly
  48       }
  49       type;
  50
  51       int pattern_length;
  52       struct synth_bird_signature pattern[];
  53    }
  54    settings;
  55 };
  56
  57 #define DEFAULT_VOL 1.0f,0.5f,0.2f,0.125f
  58 #define DEFAULT_TONES { {1,1}, {6,5}, {8,7}, {13,12} }
  59 #define DEFAULT_RISE 0.00090702947f
  60 #define DEFAULT_FALL 0.00226757369f
  61
  62 static struct synth_bird_settings synth_bird__default_settings =
  63 {
  64    .tones = DEFAULT_TONES,
  65    .type  = k_bird_lfo_sine_approx,
  66    .adsr_rise = DEFAULT_RISE,
  67    .adsr_fall = DEFAULT_FALL
  68 };
  69
  70 static struct synth_bird_signature synth_bird__warbling_vireo[] =
  71 {
  72    /* timing    fundemental            volumes       lfo hz,depth */
  73    {0.13,0.10,  4000,100,100,0,        DEFAULT_VOL,  60,200 },
  74    {0.10,0.05,  4200,-500,1700,0,      DEFAULT_VOL,  60,96  },
  75    {0.10,0.00,  2400,-1200,1000,1700,  DEFAULT_VOL,  60,96  },
  76    {0.06,0.04,  3100,200,-10,-1100,    DEFAULT_VOL,  60,90  },
  77    {0.13,0.07,  4600,-2000,0,1300,     DEFAULT_VOL,  60,10  },
  78    {0.05,0.00,  2700,-300,700,800,     DEFAULT_VOL,  60,10  },
  79    {0.09,0.07,  3600,-300,0,0,         DEFAULT_VOL,  60,20  },
  80    {0.05,0.07,  4800,1240,300,0,       DEFAULT_VOL,  60,20  },
  81    {0.08,0.02,  2700,-800,150,1000,    DEFAULT_VOL,  60,160 },
  82    {0.12,0.08,  2700,-800,150,1000,    DEFAULT_VOL,  60,160 },
  83    {0.10,0.04,  6300,-100,-3200,1000,  DEFAULT_VOL,  60,100 },
  84    {0.16,0.10,  4260,-200,300,1100,    DEFAULT_VOL,  60,20  }
  85 };
  86
  87 static struct synth_bird_signature synth_bird__pied_monarch[] =
  88 {
  89    /* timing    fundemental       volumes        lfo hz,depth */
  90    {0.18,0.13,  2200,700,-300,0,  0.6,0.05,0,0,  60,0  },
  91    {0.17,0.12,  2200,700,-300,0,  0.8,0.05,0,0,  60,0  },
  92    {0.16,0.11,  2200,700,-300,0,  0.9,0.05,0,0,  60,0  },
  93    {0.14,0.09,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  94    {0.12,0.07,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  95    {0.11,0.06,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  96    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  97    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  98    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
  99    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 100    {0.10,0.05,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  },
 101    {0.10,0.10,  2200,700,-300,0,  1.0,0.05,0,0,  60,0  }
 102 };
 103
 104 static struct synth_bird_signature synth_bird__bridled_honeyeater[] =
 105 {
 106    /* timing    fundemental        volumes               lfo hz,depth */
 107    {0.10,0.10,  2000,-1000,600,0,  1.00,0.00,0.00,0.00,  30,60},
 108    {0.10,0.10,  4000,0,-200,-200,  0.80,0.25,0.25,0.25,  30,60},
 109    {0.06,0.01,  4000,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 110    {0.07,0.01,  3950,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 111    {0.08,0.01,  3900,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 112    {0.09,0.01,  3850,0,-700,-800,  0.90,0.10,0.00,0.00,  60,20},
 113    {0.10,0.02,  3800,0,-700,-800,  0.90,0.20,0.10,0.00,  60,20},
 114    {0.11,0.05,  3750,0,-700,-800,  0.90,0.40,0.20,0.00,  60,20},
 115    {0.12,0.20,  3700,0,-700,-800,  0.30,0.10,0.00,0.00,  60,20},
 116    {0.10,0.10,  2600,1300,600,0,   0.97,0.03,0.00,0.00,  60,20},
 117 };
 118
 119 static struct synth_bird_signature synth_bird__cricket[] =
 120 {
 121    /* timing   fundemental   volumes              lfo hz, depth */
 122    {0.10,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 123    {0.11,0.14, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 124    {0.13,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 125    {0.09,0.16, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 126    {0.10,0.12, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 127    {0.10,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 128    {0.11,0.14, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 129    {0.13,0.15, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 130    {0.09,0.16, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200},
 131    {0.10,0.12, 5000,0,0,100, 0.25,0.25,0.25,0.25, 40,200}
 132 };
 133
 134 static struct synth_bird_signature synth_bird__gray_shrikethrush[] =
 135 {
 136    /* timing   fundemental         volumes             lfo hz, depth */
 137    { 0.13,0.1, 2600,-200,-100,200, 0.9,0.1,0.05,0.001, 60,10 }
 138 };
 139
 140 static struct synth_bird_signature synth_bird__boobook[] =
 141 {
 142    /* timing  fundemental     volumes           lfo hz, depth */
 143    {0.3,0.14, 700,0,-100,100, 0.9,0.14,0.0,0.2, 30,18},
 144    {0.3,1.20, 630,0,-100,100, 0.9,0.00,0.3,0.0, 30,18}
 145 };
 146
 147 static struct synth_bird_signature synth_bird__shrike_tit[] =
 148 {
 149    /* timing   fundemental         volumes           lfo hz, depth */
 150    {0.6,1.4,   2300,-300,-100,100, 1.0,0.14,0.0,0.1, 60,5 }
 151 };
 152
 153 /* sine functions over the range [0, 44100] : [-pi, pi].
 154  * Not accurate! */
 155
 156 static float sine_1second_1( int o )
 157 {
 158    float s = (o<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 159    float t = ((float)o*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s*0.5f;
 160    float t2 = t*t;
 161    float t4 = t2*t2;
 162    return s*(5.0f*t2-4.0f*t4-1.0f);
 163 }
 164
 165 static void sine_1second_4( int o[4], float v[4] )
 166 {
 167    float s[4],t[4],t2[4],t4[4];
 168    s[0] = (o[0]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 169    s[1] = (o[1]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 170    s[2] = (o[2]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 171    s[3] = (o[3]<(BIRD_SAMPLE_RATE/2))?-1.0f:1.0f;
 172
 173    t[0] = ((float)o[0]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[0]*0.5f;
 174    t[1] = ((float)o[1]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[1]*0.5f;
 175    t[2] = ((float)o[2]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[2]*0.5f;
 176    t[3] = ((float)o[3]*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f - s[3]*0.5f;
 177
 178    t2[0] = t[0]*t[0];
 179    t2[1] = t[1]*t[1];
 180    t2[2] = t[2]*t[2];
 181    t2[3] = t[3]*t[3];
 182
 183    t4[0] = t2[0]*t2[0];
 184    t4[1] = t2[1]*t2[1];
 185    t4[2] = t2[2]*t2[2];
 186    t4[3] = t2[3]*t2[3];
 187
 188    v[0] = s[0]*(5.0f*t2[0]-4.0f*t4[0]-1.0f);
 189    v[1] = s[1]*(5.0f*t2[1]-4.0f*t4[1]-1.0f);
 190    v[2] = s[2]*(5.0f*t2[2]-4.0f*t4[2]-1.0f);
 191    v[3] = s[3]*(5.0f*t2[3]-4.0f*t4[3]-1.0f);
 192 }
 193
 194 static float saw_1second_1( int o )
 195 {
 196    float t = ((float)o*(1.0f/(float)(BIRD_SAMPLE_RATE/2)))-1.0f,
 197          tt = t*t,
 198          ttt = tt*t;
 199
 200    return -2.5f*ttt+2.5f*t;
 201 }
 202
 203 static u32 synth_bird_get_length_in_samples( struct synth_bird *bird )
 204 {
 205    u32 total = 0;
 206
 207    for( int i=0; i<bird->settings.pattern_length; i ++ )
 208    {
 209       struct synth_bird_signature *sig = &bird->settings.pattern[i];
 210
 211       u32 l = sig->length * (float)BIRD_SAMPLE_RATE,
 212           p = sig->pause  * (float)BIRD_SAMPLE_RATE;
 213
 214       total += l+p;
 215    }
 216
 217    return total;
 218 }
 219
 220 static void synth_bird_reset( struct synth_bird *bird )
 221 {
 222    bird->rt.osc_main[0] = 0;
 223    bird->rt.osc_main[1] = 0;
 224    bird->rt.osc_main[2] = 0;
 225    bird->rt.osc_main[3] = 0;
 226    bird->rt.osc_lfo = 0;
 227
 228    bird->rt.volume[0] = 0.0f;
 229    bird->rt.volume[1] = 0.0f;
 230    bird->rt.volume[2] = 0.0f;
 231    bird->rt.volume[3] = 0.0f;
 232
 233    bird->rt.fundamental = 0.0f;
 234    bird->rt.x = 0;
 235    bird->rt.length = bird->settings.pattern[0].length * (float)BIRD_SAMPLE_RATE;
 236    bird->rt.gate = 1;
 237    bird->rt.adsr = 0;
 238    bird->rt.frame = 0;
 239    bird->rt.lfo_hz = 0;
 240    bird->rt.fm_depth = 0.0f;
 241
 242    bird->rt.adsr_rise = bird->settings.adsr_rise * (float)BIRD_SAMPLE_RATE;
 243    bird->rt.adsr_fall = bird->settings.adsr_fall * (float)BIRD_SAMPLE_RATE;
 244 }
 245
 246 static u32 synth_bird_save_size( struct synth_bird *bird )
 247 {
 248    return sizeof(struct synth_bird_signature) * bird->settings.pattern_length +
 249           sizeof(struct synth_bird_settings);
 250 }
 251
 252 static void synth_bird_save( struct synth_bird *bird, void *txt )
 253 {
 254    void *src = &bird->settings;
 255    vg_bin_str( src, txt, synth_bird_save_size( bird ) );
 256 }
 257
 258 #if 0
 259 static void synth_bird_load( struct synth_bird *bird,
 260                              const char *txt, u32 length )
 261 {
 262    vg_str_bin( txt, &bird->settings, length );
 263    synth_bird_reset( bird );
 264 }
 265
 266 /* expects a null terminated string */
 267 static u32 synth_bird_memory_requirement( u32 string_length )
 268 {
 269    return (string_length/2) +
 270             sizeof(struct synth_bird) - sizeof(struct synth_bird_settings);
 271 }
 272 #endif
 273
 274 #ifdef SYNTH_BIRD_STDLIB
 275 #include "stdlib.h"
 276 #include "string.h"
 277
 278 static struct synth_bird *synth_bird_create(
 279                            struct synth_bird_settings *settings,
 280                            struct synth_bird_signature *pattern,
 281                            u32 pattern_length )
 282 {
 283    u32 pattern_size = sizeof( struct synth_bird_signature ) * pattern_length;
 284    u32 total_size = sizeof( struct synth_bird ) + pattern_size;
 285    struct synth_bird *bird = malloc( total_size );
 286
 287    bird->settings = *settings;
 288
 289    memcpy( bird->settings.pattern, pattern, pattern_size );
 290    bird->settings.pattern_length = pattern_length;
 291
 292    synth_bird_reset( bird );
 293    return bird;
 294 }
 295
 296 #endif
 297
 298 static void synth_bird_think( struct synth_bird *bird )
 299 {
 300    struct synth_bird_signature *sig = &bird->settings.pattern[ bird->rt.frame ];
 301
 302    bird->rt.x ++;
 303    if( bird->rt.x >= bird->rt.length )
 304    {
 305       if( bird->rt.gate && (sig->pause != 0.0f) )
 306       {
 307          bird->rt.gate = 0;
 308          bird->rt.length = sig->pause * (float)BIRD_SAMPLE_RATE;
 309       }
 310       else
 311       {
 312          bird->rt.frame ++;
 313
 314          if( bird->rt.frame >= bird->settings.pattern_length )
 315             bird->rt.frame = 0;
 316
 317          sig = &bird->settings.pattern[ bird->rt.frame ];
 318
 319          bird->rt.gate = 1;
 320          bird->rt.length = sig->length * (float)BIRD_SAMPLE_RATE;
 321       }
 322
 323       bird->rt.x = 0;
 324    }
 325
 326    if( bird->rt.gate )
 327    {
 328       bird->rt.adsr += bird->rt.adsr_rise;
 329       if( bird->rt.adsr > BIRD_SAMPLE_RATE )
 330          bird->rt.adsr = BIRD_SAMPLE_RATE;
 331    }
 332    else
 333    {
 334       bird->rt.adsr -= bird->rt.adsr_fall;
 335       if( bird->rt.adsr < 0 )
 336          bird->rt.adsr = 0;
 337    }
 338
 339    if( bird->rt.gate )
 340    {
 341       float l = (float)bird->rt.length,
 342             t = ((float)bird->rt.x * (1.0f/l))*2.0f - 1.0f,
 343             tt = t*t,
 344             ttt = tt*t;
 345
 346       bird->rt.fundamental = sig->x0 + t*sig->x1 + tt*sig->x2 + ttt*sig->x3;
 347    }
 348
 349    float vol = (float)bird->rt.adsr * (1.0f/(float)BIRD_SAMPLE_RATE);
 350
 351    bird->rt.fm_depth  = sig->fm;
 352    bird->rt.lfo_hz    = sig->lfo_hz;
 353    bird->rt.volume[0] = sig->v0 * vol;
 354    bird->rt.volume[1] = sig->v1 * vol;
 355    bird->rt.volume[2] = sig->v2 * vol;
 356    bird->rt.volume[3] = sig->v3 * vol;
 357 }
 358
 359 static inline void int_add_mod( int *a, int const b )
 360 {
 361    *a += b;
 362
 363    if( *a > BIRD_SAMPLE_RATE )
 364       *a -= BIRD_SAMPLE_RATE;
 365 }
 366
 367 static void synth_bird_generate_samples( struct synth_bird *bird,
 368                                         float *stereo_buffer, int samples )
 369 {
 370    for( int _=0; _<samples; _++ )
 371    {
 372       synth_bird_think( bird );
 373
 374       int_add_mod( &bird->rt.osc_lfo, bird->rt.lfo_hz );
 375       float fm = sine_1second_1( bird->rt.osc_lfo ) * bird->rt.fm_depth;
 376
 377       int freq = bird->rt.fundamental + fm;
 378       int hz[4] =
 379       {
 380          (freq * bird->settings.tones[0][0]) / bird->settings.tones[0][1],
 381          (freq * bird->settings.tones[1][0]) / bird->settings.tones[1][1],
 382          (freq * bird->settings.tones[2][0]) / bird->settings.tones[2][1],
 383          (freq * bird->settings.tones[3][0]) / bird->settings.tones[3][1],
 384       };
 385
 386       int_add_mod( bird->rt.osc_main + 0, hz[0] );
 387       int_add_mod( bird->rt.osc_main + 1, hz[1] );
 388       int_add_mod( bird->rt.osc_main + 2, hz[2] );
 389       int_add_mod( bird->rt.osc_main + 3, hz[3] );
 390
 391       float v[4];
 392       sine_1second_4( bird->rt.osc_main, v );
 393
 394       float s = v[0] * bird->rt.volume[0] +
 395                 v[1] * bird->rt.volume[1] +
 396                 v[2] * bird->rt.volume[2] +
 397                 v[3] * bird->rt.volume[3] ;
 398
 399       stereo_buffer[ _*2+0 ] = s;
 400       stereo_buffer[ _*2+1 ] = s;
 401    }
 402 }
 403
 404 #ifdef SYNTH_BIRD_STDLIB
 405 #include "stdio.h"
 406
 407 #define KNRM  "\x1B[00m"
 408 #define KRED  "\x1B[31m"
 409 #define KGRN  "\x1B[32m"
 410 #define KYEL  "\x1B[33m"
 411 #define KBLU  "\x1B[34m"
 412 #define KMAG  "\x1B[35m"
 413 #define KCYN  "\x1B[36m"
 414 #define KWHT  "\x1B[37m"
 415
 416 #define LOG_BAR0 "               .               |"
 417 #define LOG_BAR1 "-------+-------+-------+-------+"
 418 #define LOG_BAR2     "                            "
 419
 420 static void synth_bird_log_pattern( struct synth_bird *bird )
 421 {
 422    synth_bird_reset( bird );
 423
 424    char output[][400]= {
 425 KNRM "9k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 426 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 427 KNRM "8k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 428 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 429 KNRM "7k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 430 KNRM "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 431 KMAG "6k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 432 KMAG "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 433 KCYN "5k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 434 KCYN "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 435 KBLU "4k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 436 KBLU "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 437 KGRN "3k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 438 KGRN "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 439 KYEL "2k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 440 KYEL "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 441 KRED "1k-"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 442 KRED "  -"   LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0      LOG_BAR0,
 443 KWHT "  +"   LOG_BAR1      LOG_BAR1      LOG_BAR1      LOG_BAR1      LOG_BAR1
 444 KWHT "  0.0s"LOG_BAR2"0.5s"LOG_BAR2"1.0s"LOG_BAR2"1.5s"LOG_BAR2"2.0s"LOG_BAR2
 445    };
 446
 447    for( int i=0; i<190*8; i++ )
 448    {
 449       for( int j=0; j<BIRD_SAMPLE_RATE/(32*8*2); j++ )
 450          synth_bird_think( bird );
 451
 452       float hz = bird->rt.fundamental / 500.0f;
 453       int j = hz;
 454
 455       if( j < 0 ) j = 0;
 456       if( j > 18 ) j = 18;
 457       j = 18-j;
 458
 459       float level = bird->rt.adsr;
 460             level *= (1.0f/(float)BIRD_SAMPLE_RATE);
 461
 462       int ch = level*3.0f;
 463
 464       if( ch )
 465          output[j][(i/8)+7] = " *###"[ch];
 466    }
 467
 468    for( int i=0; i<20; i++ )
 469    {
 470       puts( output[i] );
 471    }
 472 }
 473 #endif
 474
 475 #endif /* VG_AUDIO_SYNTH_BIRD_H */