libs/plugins/a-comp.lv2/a-comp.c

   1 /* a-comp
   2  * Copyright (C) 2016 Damien Zammit <damien@zamaudio.com>
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License
   6  * as published by the Free Software Foundation; either version 2
   7  * of the License, or (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14
  15 #include <math.h>
  16 #include <stdlib.h>
  17 #include <string.h>
  18 #include <stdbool.h>
  19
  20 #ifdef LV2_EXTENDED
  21 #include <cairo/cairo.h>
  22 #include "ardour/lv2_extensions.h"
  23 #endif
  24
  25 #include "lv2/lv2plug.in/ns/lv2core/lv2.h"
  26
  27 #define ACOMP_URI "urn:ardour:a-comp"
  28
  29 typedef enum {
  30         ACOMP_INPUT0 = 0,
  31         ACOMP_INPUT1,
  32         ACOMP_OUTPUT,
  33
  34         ACOMP_ATTACK,
  35         ACOMP_RELEASE,
  36         ACOMP_KNEE,
  37         ACOMP_RATIO,
  38         ACOMP_THRESHOLD,
  39         ACOMP_MAKEUP,
  40
  41         ACOMP_GAINR,
  42         ACOMP_OUTLEVEL,
  43         ACOMP_SIDECHAIN,
  44 } PortIndex;
  45
  46
  47 typedef struct {
  48         float* input0;
  49         float* input1;
  50         float* output;
  51
  52         float* attack;
  53         float* release;
  54         float* knee;
  55         float* ratio;
  56         float* thresdb;
  57         float* makeup;
  58
  59         float* gainr;
  60         float* outlevel;
  61         float* sidechain;
  62
  63         float srate;
  64         float old_yl;
  65         float old_y1;
  66         float old_yg;
  67
  68 #ifdef LV2_EXTENDED
  69         bool                     need_expose;
  70         LV2_Inline_Display_Image_Surface surf;
  71         cairo_surface_t*         display;
  72         LV2_Inline_Display*      queue_draw;
  73         uint32_t                 w, h;
  74
  75         /* ports pointers are only valid during run so we'll
  76          * have to cache them for the display, besides
  77          * we do want to check for changes
  78          */
  79         float v_knee;
  80         float v_ratio;
  81         float v_thresdb;
  82         float v_lvl;
  83         float v_lvl_in;
  84         float v_lvl_out;
  85 #endif
  86 } AComp;
  87
  88 static LV2_Handle
  89 instantiate(const LV2_Descriptor* descriptor,
  90             double rate,
  91             const char* bundle_path,
  92             const LV2_Feature* const* features)
  93 {
  94         AComp* acomp = (AComp*)calloc(1, sizeof(AComp));
  95
  96         for (int i=0; features[i]; ++i) {
  97 #ifdef LV2_EXTENDED
  98                 if (!strcmp(features[i]->URI, LV2_INLINEDISPLAY__queue_draw)) {
  99                         acomp->queue_draw = (LV2_Inline_Display*) features[i]->data;
 100                 }
 101 #endif
 102         }
 103
 104         acomp->srate = rate;
 105         acomp->old_yl=acomp->old_y1=acomp->old_yg=0.f;
 106         acomp->need_expose = true;
 107
 108         return (LV2_Handle)acomp;
 109 }
 110
 111 static void
 112 connect_port(LV2_Handle instance,
 113              uint32_t port,
 114              void* data)
 115 {
 116         AComp* acomp = (AComp*)instance;
 117
 118         switch ((PortIndex)port) {
 119         case ACOMP_ATTACK:
 120                 acomp->attack = (float*)data;
 121                 break;
 122         case ACOMP_RELEASE:
 123                 acomp->release = (float*)data;
 124                 break;
 125         case ACOMP_KNEE:
 126                 acomp->knee = (float*)data;
 127                 break;
 128         case ACOMP_RATIO:
 129                 acomp->ratio = (float*)data;
 130                 break;
 131         case ACOMP_THRESHOLD:
 132                 acomp->thresdb = (float*)data;
 133                 break;
 134         case ACOMP_MAKEUP:
 135                 acomp->makeup = (float*)data;
 136                 break;
 137         case ACOMP_GAINR:
 138                 acomp->gainr = (float*)data;
 139                 break;
 140         case ACOMP_OUTLEVEL:
 141                 acomp->outlevel = (float*)data;
 142                 break;
 143         case ACOMP_SIDECHAIN:
 144                 acomp->sidechain = (float*)data;
 145                 break;
 146         case ACOMP_INPUT0:
 147                 acomp->input0 = (float*)data;
 148                 break;
 149         case ACOMP_INPUT1:
 150                 acomp->input1 = (float*)data;
 151                 break;
 152         case ACOMP_OUTPUT:
 153                 acomp->output = (float*)data;
 154                 break;
 155         }
 156 }
 157
 158 // Force already-denormal float value to zero
 159 static inline float
 160 sanitize_denormal(float value) {
 161         if (!isnormal(value)) {
 162                 value = 0.f;
 163         }
 164         return value;
 165 }
 166
 167 static inline float
 168 from_dB(float gdb) {
 169         return (exp(gdb/20.f*log(10.f)));
 170 }
 171
 172 static inline float
 173 to_dB(float g) {
 174         return (20.f*log10(g));
 175 }
 176
 177 static void
 178 activate(LV2_Handle instance)
 179 {
 180         AComp* acomp = (AComp*)instance;
 181
 182         *(acomp->gainr) = 0.0f;
 183         *(acomp->outlevel) = -45.0f;
 184         acomp->old_yl=acomp->old_y1=acomp->old_yg=0.f;
 185 }
 186
 187 static void
 188 run(LV2_Handle instance, uint32_t n_samples)
 189 {
 190         AComp* acomp = (AComp*)instance;
 191
 192         const float* const input0 = acomp->input0;
 193         const float* const input1 = acomp->input1;
 194         float* const output = acomp->output;
 195
 196         float srate = acomp->srate;
 197         float width = (6.f * *(acomp->knee)) + 0.01;
 198         float cdb=0.f;
 199         float attack_coeff = exp(-1000.f/(*(acomp->attack) * srate));
 200         float release_coeff = exp(-1000.f/(*(acomp->release) * srate));
 201
 202         float max = 0.f;
 203         float lgaininp = 0.f;
 204         float Lgain = 1.f;
 205         float Lxg, Lxl, Lyg, Lyl, Ly1;
 206         int usesidechain = (*(acomp->sidechain) < 0.5) ? 0 : 1;
 207         uint32_t i;
 208         float ingain;
 209         float in0;
 210         float in1;
 211         float ratio = *(acomp->ratio);
 212         float thresdb = *(acomp->thresdb);
 213
 214 #ifdef LV2_EXTENDED
 215         if (acomp->v_knee != *acomp->knee) {
 216                 acomp->v_knee = *acomp->knee;
 217                 acomp->need_expose = true;
 218         }
 219
 220         if (acomp->v_ratio != *acomp->ratio) {
 221                 acomp->v_ratio = *acomp->ratio;
 222                 acomp->need_expose = true;
 223         }
 224
 225         if (acomp->v_thresdb != *acomp->thresdb) {
 226                 acomp->v_thresdb = *acomp->thresdb;
 227                 acomp->need_expose = true;
 228         }
 229 #endif
 230
 231         float in_peak = 0;
 232
 233         for (i = 0; i < n_samples; i++) {
 234                 in0 = input0[i];
 235                 in1 = input1[i];
 236                 ingain = usesidechain ? in1 : in0;
 237                 Lyg = 0.f;
 238                 Lxg = (ingain==0.f) ? -160.f : to_dB(fabs(ingain));
 239                 Lxg = sanitize_denormal(Lxg);
 240
 241                 Lyg = Lxg + (1.f/ratio-1.f)*(Lxg-thresdb+width/2.f)*(Lxg-thresdb+width/2.f)/(2.f*width);
 242
 243                 if (2.f*(Lxg-thresdb) < -width) {
 244                         Lyg = Lxg;
 245                 } else {
 246                         Lyg = thresdb + (Lxg-thresdb)/ratio;
 247                         Lyg = sanitize_denormal(Lyg);
 248                 }
 249
 250                 Lxl = Lxg - Lyg;
 251
 252                 acomp->old_y1 = sanitize_denormal(acomp->old_y1);
 253                 acomp->old_yl = sanitize_denormal(acomp->old_yl);
 254                 Ly1 = fmaxf(Lxl, release_coeff * acomp->old_y1+(1.f-release_coeff)*Lxl);
 255                 Lyl = attack_coeff * acomp->old_yl+(1.f-attack_coeff)*Ly1;
 256                 Ly1 = sanitize_denormal(Ly1);
 257                 Lyl = sanitize_denormal(Lyl);
 258
 259                 cdb = -Lyl;
 260                 Lgain = from_dB(cdb);
 261
 262                 *(acomp->gainr) = Lyl;
 263
 264                 if (in0 > in_peak) {
 265                         in_peak = in0;
 266                 }
 267                 lgaininp = in0 * Lgain;
 268                 output[i] = lgaininp * from_dB(*(acomp->makeup));
 269
 270                 max = (fabsf(output[i]) > max) ? fabsf(output[i]) : sanitize_denormal(max);
 271
 272                 // TODO re-use local variables on stack
 273                 // store values back to acomp at the end of the inner-loop
 274                 acomp->old_yl = Lyl;
 275                 acomp->old_y1 = Ly1;
 276                 acomp->old_yg = Lyg;
 277         }
 278
 279         *(acomp->outlevel) = (max < 0.0056f) ? -45.f : to_dB(max);
 280
 281 #ifdef LV2_EXTENDED
 282         acomp->v_lvl += .1 * (in_peak - acomp->v_lvl);  // crude LPF TODO use n_samples/rate TC
 283         const float v_lvl_in = (acomp->v_lvl < 0.001f) ? -60.f : to_dB(acomp->v_lvl);
 284         const float v_lvl_out = (max < 0.001f) ? -60.f : to_dB(max);
 285         if (fabsf (acomp->v_lvl_out - v_lvl_out) >= 1 || fabsf (acomp->v_lvl_in - v_lvl_in) >= 1) {
 286                 // >= 1dB difference
 287                 acomp->need_expose = true;
 288                 acomp->v_lvl_in = v_lvl_in;
 289                 acomp->v_lvl_out = v_lvl_out - *acomp->makeup;
 290         }
 291         if (acomp->need_expose && acomp->queue_draw) {
 292                 acomp->need_expose = false;
 293                 acomp->queue_draw->queue_draw (acomp->queue_draw->handle);
 294         }
 295 #endif
 296 }
 297
 298 static void
 299 deactivate(LV2_Handle instance)
 300 {
 301         activate(instance);
 302 }
 303
 304 static void
 305 cleanup(LV2_Handle instance)
 306 {
 307 #ifdef LV2_EXTENDED
 308         AComp* acomp = (AComp*)instance;
 309         if (acomp->display) {
 310                 cairo_surface_destroy (acomp->display);
 311         }
 312 #endif
 313
 314         free(instance);
 315 }
 316
 317
 318 #ifndef MIN
 319 #define MIN(A,B) ((A) < (B)) ? (A) : (B)
 320 #endif
 321
 322 #ifdef LV2_EXTENDED
 323 static float
 324 comp_curve (AComp* self, float xg) {
 325         const float knee = self->v_knee;
 326         const float ratio = self->v_ratio;
 327         const float thresdb = self->v_thresdb;
 328
 329         const float width = 6.f * knee + 0.01f;
 330         float yg = 0.f;
 331
 332         if (2.f * (xg - thresdb) < -width) {
 333                 yg = xg;
 334         } else if (2.f * fabs (xg - thresdb) <= width) {
 335                 yg = xg + (1.f / ratio - 1.f ) * (xg - thresdb + width / 2.f) * (xg - thresdb + width / 2.f) / (2.f * width);
 336         } else if (2.f * (xg - thresdb) > width) {
 337                 yg = thresdb + (xg - thresdb) / ratio;
 338         }
 339         return yg;
 340 }
 341
 342 static LV2_Inline_Display_Image_Surface *
 343 render_inline (LV2_Handle instance, uint32_t w, uint32_t max_h)
 344 {
 345         AComp* self = (AComp*)instance;
 346         uint32_t h = MIN (w, max_h);
 347
 348         if (!self->display || self->w != w || self->h != h) {
 349                 if (self->display) cairo_surface_destroy(self->display);
 350                 self->display = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, w, h);
 351                 self->w = w;
 352                 self->h = h;
 353         }
 354
 355         cairo_t* cr = cairo_create (self->display);
 356
 357         // clear background
 358         cairo_rectangle (cr, 0, 0, w, h);
 359         cairo_set_source_rgba (cr, .2, .2, .2, 1.0);
 360         cairo_fill (cr);
 361
 362         cairo_set_line_width(cr, 1.0);
 363
 364         // draw grid 10dB steps
 365         const double dash1[] = {1, 2};
 366         const double dash2[] = {1, 3};
 367         cairo_save (cr);
 368         cairo_set_line_cap(cr, CAIRO_LINE_CAP_ROUND);
 369         cairo_set_dash(cr, dash2, 2, 2);
 370         cairo_set_source_rgba (cr, 0.5, 0.5, 0.5, 0.5);
 371
 372         for (uint32_t d = 1; d < 6; ++d) {
 373                 const float x = -.5 + floorf (w * (d * 10.f / 60.f));
 374                 const float y = -.5 + floorf (h * (d * 10.f / 60.f));
 375
 376                 cairo_move_to (cr, x, 0);
 377                 cairo_line_to (cr, x, h);
 378                 cairo_stroke (cr);
 379
 380                 cairo_move_to (cr, 0, y);
 381                 cairo_line_to (cr, w, y);
 382                 cairo_stroke (cr);
 383         }
 384         if (self->v_thresdb < 0) {
 385                 cairo_set_source_rgba (cr, 0.5, 0.5, 0.5, 1.0);
 386                 const float y = -.5 + floorf (h * (self->v_thresdb / -60.f));
 387                 cairo_set_dash(cr, dash1, 2, 2);
 388                 cairo_move_to (cr, 0, y);
 389                 cairo_line_to (cr, w, y);
 390                 cairo_stroke (cr);
 391                 cairo_move_to (cr, 0, h);
 392                 cairo_line_to (cr, w, 0);
 393                 cairo_stroke (cr);
 394         }
 395         cairo_restore (cr);
 396
 397
 398         // draw curve
 399         cairo_set_source_rgba (cr, .8, .8, .8, 1.0);
 400         cairo_move_to (cr, 0, h);
 401
 402         for (uint32_t x = 0; x < w; ++x) {
 403                 // plot -60..0  dB
 404                 const float x_db = 60.f * (-1.f + x / (float)w);
 405                 const float y_db = comp_curve (self, x_db);
 406                 const float y = h * (y_db / -60.f);
 407                 cairo_line_to (cr, x, y);
 408         }
 409         cairo_stroke_preserve (cr);
 410
 411         cairo_line_to (cr, w, h);
 412         cairo_close_path (cr);
 413         cairo_clip (cr);
 414
 415         // draw signal level & reduction/gradient
 416         const float top = comp_curve (self, 0);
 417         cairo_pattern_t* pat = cairo_pattern_create_linear (0.0, 0.0, 0.0, h);
 418         if (top > self->v_thresdb) {
 419                 cairo_pattern_add_color_stop_rgba (pat, 0.0, 0.8, 0.1, 0.1, 0.5);
 420                 cairo_pattern_add_color_stop_rgba (pat, top / -60.f, 0.8, 0.1, 0.1, 0.5);
 421         }
 422         if (self->v_knee > 0) {
 423                 cairo_pattern_add_color_stop_rgba (pat, (self->v_thresdb / -60.f), 0.7, 0.7, 0.2, 0.5);
 424                 cairo_pattern_add_color_stop_rgba (pat, ((self->v_thresdb - self->v_knee) / -60.f), 0.5, 0.5, 0.5, 0.5);
 425         } else {
 426                 cairo_pattern_add_color_stop_rgba (pat, (self->v_thresdb / -60.f), 0.7, 0.7, 0.2, 0.5);
 427                 cairo_pattern_add_color_stop_rgba (pat, ((self->v_thresdb - .01) / -60.f), 0.5, 0.5, 0.5, 0.5);
 428         }
 429         cairo_pattern_add_color_stop_rgba (pat, 1.0, 0.5, 0.5, 0.5, 0.5);
 430
 431         // maybe cut off at x-position?
 432         const float x = w * (self->v_lvl_in + 60) / 60.f;
 433         const float y = h * (self->v_lvl_out + 60) / 60.f;
 434         cairo_rectangle (cr, 0, h - y, x, y);
 435         if (self->v_ratio > 1.0) {
 436                 cairo_set_source (cr, pat);
 437         } else {
 438                 cairo_set_source_rgba (cr, 0.5, 0.5, 0.5, 0.5);
 439         }
 440         cairo_fill (cr);
 441
 442         cairo_pattern_destroy (pat); // TODO cache pattern
 443
 444
 445         // create RGBA surface
 446         cairo_destroy (cr);
 447         cairo_surface_flush (self->display);
 448         self->surf.width = cairo_image_surface_get_width (self->display);
 449         self->surf.height = cairo_image_surface_get_height (self->display);
 450         self->surf.stride = cairo_image_surface_get_stride (self->display);
 451         self->surf.data = cairo_image_surface_get_data  (self->display);
 452
 453         return &self->surf;
 454 }
 455 #endif
 456
 457 static const void*
 458 extension_data(const char* uri)
 459 {
 460         static const LV2_Inline_Display_Interface display  = { render_inline };
 461         if (!strcmp(uri, LV2_INLINEDISPLAY__interface)) {
 462                 return &display;
 463         }
 464         return NULL;
 465 }
 466
 467 static const LV2_Descriptor descriptor = {
 468         ACOMP_URI,
 469         instantiate,
 470         connect_port,
 471         activate,
 472         run,
 473         deactivate,
 474         cleanup,
 475         extension_data
 476 };
 477
 478 LV2_SYMBOL_EXPORT
 479 const LV2_Descriptor*
 480 lv2_descriptor(uint32_t index)
 481 {
 482         switch (index) {
 483         case 0:
 484                 return &descriptor;
 485         default:
 486                 return NULL;
 487         }
 488 }