gst/equalizer/gstiirequalizer.c

   1 /* GStreamer
   2  * Copyright (C) <2004> Benjamin Otte <otte@gnome.org>
   3  *               <2007> Stefan Kost <ensonic@users.sf.net>
   4  *               <2007> Sebastian Dröge <slomo@circular-chaos.org>
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Library General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Library General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Library General Public
  17  * License along with this library; if not, write to the
  18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19  * Boston, MA 02111-1307, USA.
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include "config.h"
  24 #endif
  25
  26 #include <math.h>
  27 #include <string.h>
  28
  29 #include "gstiirequalizer.h"
  30 #include "gstiirequalizernbands.h"
  31 #include "gstiirequalizer3bands.h"
  32 #include "gstiirequalizer10bands.h"
  33
  34 GST_DEBUG_CATEGORY (equalizer_debug);
  35 #define GST_CAT_DEFAULT equalizer_debug
  36
  37 #define BANDS_LOCK(equ) g_mutex_lock(equ->bands_lock)
  38 #define BANDS_UNLOCK(equ) g_mutex_unlock(equ->bands_lock)
  39
  40 static void gst_iir_equalizer_child_proxy_interface_init (gpointer g_iface,
  41     gpointer iface_data);
  42
  43 static void gst_iir_equalizer_finalize (GObject * object);
  44
  45 static gboolean gst_iir_equalizer_setup (GstAudioFilter * filter,
  46     GstRingBufferSpec * fmt);
  47 static GstFlowReturn gst_iir_equalizer_transform_ip (GstBaseTransform * btrans,
  48     GstBuffer * buf);
  49
  50 #define ALLOWED_CAPS \
  51     "audio/x-raw-int,"                                                \
  52     " depth=(int)16,"                                                 \
  53     " width=(int)16,"                                                 \
  54     " endianness=(int)BYTE_ORDER,"                                    \
  55     " signed=(bool)TRUE,"                                             \
  56     " rate=(int)[1000,MAX],"                                          \
  57     " channels=(int)[1,MAX]; "                                        \
  58     "audio/x-raw-float,"                                              \
  59     " width=(int) { 32, 64 } ,"                                       \
  60     " endianness=(int)BYTE_ORDER,"                                    \
  61     " rate=(int)[1000,MAX],"                                          \
  62     " channels=(int)[1,MAX]"
  63
  64 static void
  65 _do_init (GType object_type)
  66 {
  67   const GInterfaceInfo child_proxy_interface_info = {
  68     (GInterfaceInitFunc) gst_iir_equalizer_child_proxy_interface_init,
  69     NULL,                       /* interface_finalize */
  70     NULL                        /* interface_data */
  71   };
  72
  73   g_type_add_interface_static (object_type, GST_TYPE_CHILD_PROXY,
  74       &child_proxy_interface_info);
  75 }
  76
  77 GST_BOILERPLATE_FULL (GstIirEqualizer, gst_iir_equalizer,
  78     GstAudioFilter, GST_TYPE_AUDIO_FILTER, _do_init);
  79
  80 /* child object */
  81
  82 enum
  83 {
  84   PROP_GAIN = 1,
  85   PROP_FREQ,
  86   PROP_BANDWIDTH,
  87   PROP_TYPE
  88 };
  89
  90 typedef enum
  91 {
  92   BAND_TYPE_PEAK = 0,
  93   BAND_TYPE_LOW_SHELF,
  94   BAND_TYPE_HIGH_SHELF
  95 } GstIirEqualizerBandType;
  96
  97 #define GST_TYPE_IIR_EQUALIZER_BAND_TYPE (gst_iir_equalizer_band_type_get_type ())
  98 static GType
  99 gst_iir_equalizer_band_type_get_type (void)
 100 {
 101   static GType gtype = 0;
 102
 103   if (gtype == 0) {
 104     static const GEnumValue values[] = {
 105       {BAND_TYPE_PEAK, "Peak filter (default for inner bands)", "peak"},
 106       {BAND_TYPE_LOW_SHELF, "Low shelf filter (default for first band)",
 107           "low-shelf"},
 108       {BAND_TYPE_HIGH_SHELF, "High shelf filter (default for last band)",
 109           "high-shelf"},
 110       {0, NULL, NULL}
 111     };
 112
 113     gtype = g_enum_register_static ("GstIirEqualizerBandType", values);
 114   }
 115   return gtype;
 116 }
 117
 118
 119 typedef struct _GstIirEqualizerBandClass GstIirEqualizerBandClass;
 120
 121 #define GST_TYPE_IIR_EQUALIZER_BAND \
 122   (gst_iir_equalizer_band_get_type())
 123 #define GST_IIR_EQUALIZER_BAND(obj) \
 124   (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_IIR_EQUALIZER_BAND,GstIirEqualizerBand))
 125 #define GST_IIR_EQUALIZER_BAND_CLASS(klass) \
 126   (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_IIR_EQUALIZER_BAND,GstIirEqualizerBandClass))
 127 #define GST_IS_IIR_EQUALIZER_BAND(obj) \
 128   (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_IIR_EQUALIZER_BAND))
 129 #define GST_IS_IIR_EQUALIZER_BAND_CLASS(klass) \
 130   (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_IIR_EQUALIZER_BAND))
 131
 132 struct _GstIirEqualizerBand
 133 {
 134   GstObject object;
 135
 136   /*< private > */
 137   /* center frequency and gain */
 138   gdouble freq;
 139   gdouble gain;
 140   gdouble width;
 141   GstIirEqualizerBandType type;
 142
 143   /* second order iir filter */
 144   gdouble b1, b2;               /* IIR coefficients for outputs */
 145   gdouble a0, a1, a2;           /* IIR coefficients for inputs */
 146 };
 147
 148 struct _GstIirEqualizerBandClass
 149 {
 150   GstObjectClass parent_class;
 151 };
 152
 153 static GType gst_iir_equalizer_band_get_type (void);
 154
 155 static void
 156 gst_iir_equalizer_band_set_property (GObject * object, guint prop_id,
 157     const GValue * value, GParamSpec * pspec)
 158 {
 159   GstIirEqualizerBand *band = GST_IIR_EQUALIZER_BAND (object);
 160   GstIirEqualizer *equ =
 161       GST_IIR_EQUALIZER (gst_object_get_parent (GST_OBJECT (band)));
 162
 163   switch (prop_id) {
 164     case PROP_GAIN:{
 165       gdouble gain;
 166
 167       gain = g_value_get_double (value);
 168       GST_DEBUG_OBJECT (band, "gain = %lf -> %lf", band->gain, gain);
 169       if (gain != band->gain) {
 170         BANDS_LOCK (equ);
 171         equ->need_new_coefficients = TRUE;
 172         band->gain = gain;
 173         BANDS_UNLOCK (equ);
 174         GST_DEBUG_OBJECT (band, "changed gain = %lf ", band->gain);
 175       }
 176       break;
 177     }
 178     case PROP_FREQ:{
 179       gdouble freq;
 180
 181       freq = g_value_get_double (value);
 182       GST_DEBUG_OBJECT (band, "freq = %lf -> %lf", band->freq, freq);
 183       if (freq != band->freq) {
 184         BANDS_LOCK (equ);
 185         equ->need_new_coefficients = TRUE;
 186         band->freq = freq;
 187         BANDS_UNLOCK (equ);
 188         GST_DEBUG_OBJECT (band, "changed freq = %lf ", band->freq);
 189       }
 190       break;
 191     }
 192     case PROP_BANDWIDTH:{
 193       gdouble width;
 194
 195       width = g_value_get_double (value);
 196       GST_DEBUG_OBJECT (band, "width = %lf -> %lf", band->width, width);
 197       if (width != band->width) {
 198         BANDS_LOCK (equ);
 199         equ->need_new_coefficients = TRUE;
 200         band->width = width;
 201         BANDS_UNLOCK (equ);
 202         GST_DEBUG_OBJECT (band, "changed width = %lf ", band->width);
 203       }
 204       break;
 205     }
 206     case PROP_TYPE:{
 207       GstIirEqualizerBandType type;
 208
 209       type = g_value_get_enum (value);
 210       GST_DEBUG_OBJECT (band, "type = %d -> %d", band->type, type);
 211       if (type != band->type) {
 212         BANDS_LOCK (equ);
 213         equ->need_new_coefficients = TRUE;
 214         band->type = type;
 215         BANDS_UNLOCK (equ);
 216         GST_DEBUG_OBJECT (band, "changed type = %d ", band->type);
 217       }
 218       break;
 219     }
 220     default:
 221       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 222       break;
 223   }
 224
 225   gst_object_unref (equ);
 226 }
 227
 228 static void
 229 gst_iir_equalizer_band_get_property (GObject * object, guint prop_id,
 230     GValue * value, GParamSpec * pspec)
 231 {
 232   GstIirEqualizerBand *band = GST_IIR_EQUALIZER_BAND (object);
 233
 234   switch (prop_id) {
 235     case PROP_GAIN:
 236       g_value_set_double (value, band->gain);
 237       break;
 238     case PROP_FREQ:
 239       g_value_set_double (value, band->freq);
 240       break;
 241     case PROP_BANDWIDTH:
 242       g_value_set_double (value, band->width);
 243       break;
 244     case PROP_TYPE:
 245       g_value_set_enum (value, band->type);
 246       break;
 247     default:
 248       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
 249       break;
 250   }
 251 }
 252
 253 static void
 254 gst_iir_equalizer_band_class_init (GstIirEqualizerBandClass * klass)
 255 {
 256   GObjectClass *gobject_class = G_OBJECT_CLASS (klass);
 257
 258   gobject_class->set_property = gst_iir_equalizer_band_set_property;
 259   gobject_class->get_property = gst_iir_equalizer_band_get_property;
 260
 261   g_object_class_install_property (gobject_class, PROP_GAIN,
 262       g_param_spec_double ("gain", "gain",
 263           "gain for the frequency band ranging from -24.0 dB to +12.0 dB",
 264           -24.0, 12.0, 0.0,
 265           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
 266
 267   g_object_class_install_property (gobject_class, PROP_FREQ,
 268       g_param_spec_double ("freq", "freq",
 269           "center frequency of the band",
 270           0.0, 100000.0, 0.0,
 271           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
 272
 273   g_object_class_install_property (gobject_class, PROP_BANDWIDTH,
 274       g_param_spec_double ("bandwidth", "bandwidth",
 275           "difference between bandedges in Hz",
 276           0.0, 100000.0, 1.0,
 277           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
 278
 279   g_object_class_install_property (gobject_class, PROP_TYPE,
 280       g_param_spec_enum ("type", "Type",
 281           "Filter type", GST_TYPE_IIR_EQUALIZER_BAND_TYPE,
 282           BAND_TYPE_PEAK,
 283           G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS | GST_PARAM_CONTROLLABLE));
 284 }
 285
 286 static void
 287 gst_iir_equalizer_band_init (GstIirEqualizerBand * band,
 288     GstIirEqualizerBandClass * klass)
 289 {
 290   band->freq = 0.0;
 291   band->gain = 0.0;
 292   band->width = 1.0;
 293   band->type = BAND_TYPE_PEAK;
 294 }
 295
 296 static GType
 297 gst_iir_equalizer_band_get_type (void)
 298 {
 299   static GType type = 0;
 300
 301   if (G_UNLIKELY (!type)) {
 302     const GTypeInfo type_info = {
 303       sizeof (GstIirEqualizerBandClass),
 304       NULL,
 305       NULL,
 306       (GClassInitFunc) gst_iir_equalizer_band_class_init,
 307       NULL,
 308       NULL,
 309       sizeof (GstIirEqualizerBand),
 310       0,
 311       (GInstanceInitFunc) gst_iir_equalizer_band_init,
 312     };
 313     type =
 314         g_type_register_static (GST_TYPE_OBJECT, "GstIirEqualizerBand",
 315         &type_info, 0);
 316   }
 317   return (type);
 318 }
 319
 320
 321 /* child proxy iface */
 322 static GstObject *
 323 gst_iir_equalizer_child_proxy_get_child_by_index (GstChildProxy * child_proxy,
 324     guint index)
 325 {
 326   GstIirEqualizer *equ = GST_IIR_EQUALIZER (child_proxy);
 327   GstObject *ret;
 328
 329   BANDS_LOCK (equ);
 330   if (G_UNLIKELY (index >= equ->freq_band_count)) {
 331     BANDS_UNLOCK (equ);
 332     g_return_val_if_fail (index < equ->freq_band_count, NULL);
 333   }
 334
 335   ret = gst_object_ref (equ->bands[index]);
 336   BANDS_UNLOCK (equ);
 337
 338   GST_LOG_OBJECT (equ, "return child[%d] %" GST_PTR_FORMAT, index, ret);
 339   return ret;
 340 }
 341
 342 static guint
 343 gst_iir_equalizer_child_proxy_get_children_count (GstChildProxy * child_proxy)
 344 {
 345   GstIirEqualizer *equ = GST_IIR_EQUALIZER (child_proxy);
 346
 347   GST_LOG ("we have %d children", equ->freq_band_count);
 348   return equ->freq_band_count;
 349 }
 350
 351 static void
 352 gst_iir_equalizer_child_proxy_interface_init (gpointer g_iface,
 353     gpointer iface_data)
 354 {
 355   GstChildProxyInterface *iface = g_iface;
 356
 357   GST_DEBUG ("initializing iface");
 358
 359   iface->get_child_by_index = gst_iir_equalizer_child_proxy_get_child_by_index;
 360   iface->get_children_count = gst_iir_equalizer_child_proxy_get_children_count;
 361 }
 362
 363
 364 /* equalizer implementation */
 365
 366 static void
 367 gst_iir_equalizer_base_init (gpointer g_class)
 368 {
 369   GstAudioFilterClass *audiofilter_class = GST_AUDIO_FILTER_CLASS (g_class);
 370   GstCaps *caps;
 371
 372   caps = gst_caps_from_string (ALLOWED_CAPS);
 373   gst_audio_filter_class_add_pad_templates (audiofilter_class, caps);
 374   gst_caps_unref (caps);
 375 }
 376
 377 static void
 378 gst_iir_equalizer_class_init (GstIirEqualizerClass * klass)
 379 {
 380   GstAudioFilterClass *audio_filter_class = (GstAudioFilterClass *) klass;
 381   GstBaseTransformClass *btrans_class = (GstBaseTransformClass *) klass;
 382   GObjectClass *gobject_class = (GObjectClass *) klass;
 383
 384   gobject_class->finalize = gst_iir_equalizer_finalize;
 385   audio_filter_class->setup = gst_iir_equalizer_setup;
 386   btrans_class->transform_ip = gst_iir_equalizer_transform_ip;
 387 }
 388
 389 static void
 390 gst_iir_equalizer_init (GstIirEqualizer * eq, GstIirEqualizerClass * g_class)
 391 {
 392   eq->bands_lock = g_mutex_new ();
 393   eq->need_new_coefficients = TRUE;
 394 }
 395
 396 static void
 397 gst_iir_equalizer_finalize (GObject * object)
 398 {
 399   GstIirEqualizer *equ = GST_IIR_EQUALIZER (object);
 400   gint i;
 401
 402   for (i = 0; i < equ->freq_band_count; i++) {
 403     if (equ->bands[i])
 404       gst_object_unparent (GST_OBJECT (equ->bands[i]));
 405     equ->bands[i] = NULL;
 406   }
 407   equ->freq_band_count = 0;
 408
 409   g_free (equ->bands);
 410   g_free (equ->history);
 411
 412   g_mutex_free (equ->bands_lock);
 413
 414   G_OBJECT_CLASS (parent_class)->finalize (object);
 415 }
 416
 417 /* Filter taken from
 418  *
 419  * The Equivalence of Various Methods of Computing
 420  * Biquad Coefficients for Audio Parametric Equalizers
 421  *
 422  * by Robert Bristow-Johnson
 423  *
 424  * http://www.aes.org/e-lib/browse.cfm?elib=6326
 425  * http://www.musicdsp.org/files/EQ-Coefficients.pdf
 426  * http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
 427  *
 428  * The bandwidth method that we use here is the preferred
 429  * one from this article transformed from octaves to frequency
 430  * in Hz.
 431  */
 432 static inline gdouble
 433 arg_to_scale (gdouble arg)
 434 {
 435   return (pow (10.0, arg / 40.0));
 436 }
 437
 438 static gdouble
 439 calculate_omega (gdouble freq, gint rate)
 440 {
 441   gdouble omega;
 442
 443   if (freq / rate >= 0.5)
 444     omega = G_PI;
 445   else if (freq <= 0.0)
 446     omega = 0.0;
 447   else
 448     omega = 2.0 * G_PI * (freq / rate);
 449
 450   return omega;
 451 }
 452
 453 static gdouble
 454 calculate_bw (GstIirEqualizerBand * band, gint rate)
 455 {
 456   gdouble bw = 0.0;
 457
 458   if (band->width / rate >= 0.5) {
 459     /* If bandwidth == 0.5 the calculation below fails as tan(G_PI/2)
 460      * is undefined. So set the bandwidth to a slightly smaller value.
 461      */
 462     bw = G_PI - 0.00000001;
 463   } else if (band->width <= 0.0) {
 464     /* If bandwidth == 0 this band won't change anything so set
 465      * the coefficients accordingly. The coefficient calculation
 466      * below would create coefficients that for some reason amplify
 467      * the band.
 468      */
 469     band->a0 = 1.0;
 470     band->a1 = 0.0;
 471     band->a2 = 0.0;
 472     band->b1 = 0.0;
 473     band->b2 = 0.0;
 474   } else {
 475     bw = 2.0 * G_PI * (band->width / rate);
 476   }
 477   return bw;
 478 }
 479
 480 static void
 481 setup_peak_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band)
 482 {
 483   g_return_if_fail (GST_AUDIO_FILTER (equ)->format.rate);
 484
 485   {
 486     gdouble gain, omega, bw;
 487     gdouble alpha, alpha1, alpha2, b0;
 488
 489     gain = arg_to_scale (band->gain);
 490     omega = calculate_omega (band->freq, GST_AUDIO_FILTER (equ)->format.rate);
 491     bw = calculate_bw (band, GST_AUDIO_FILTER (equ)->format.rate);
 492     if (bw == 0.0)
 493       goto out;
 494
 495     alpha = tan (bw / 2.0);
 496
 497     alpha1 = alpha * gain;
 498     alpha2 = alpha / gain;
 499
 500     b0 = (1.0 + alpha2);
 501
 502     band->a0 = (1.0 + alpha1) / b0;
 503     band->a1 = (-2.0 * cos (omega)) / b0;
 504     band->a2 = (1.0 - alpha1) / b0;
 505     band->b1 = (2.0 * cos (omega)) / b0;
 506     band->b2 = -(1.0 - alpha2) / b0;
 507
 508   out:
 509     GST_INFO
 510         ("gain = %5.1f, width= %7.2f, freq = %7.2f, a0 = %7.5g, a1 = %7.5g, a2=%7.5g b1 = %7.5g, b2 = %7.5g",
 511         band->gain, band->width, band->freq, band->a0, band->a1, band->a2,
 512         band->b1, band->b2);
 513   }
 514 }
 515
 516 static void
 517 setup_low_shelf_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band)
 518 {
 519   g_return_if_fail (GST_AUDIO_FILTER (equ)->format.rate);
 520
 521   {
 522     gdouble gain, omega, bw;
 523     gdouble alpha, delta, b0;
 524     gdouble egp, egm;
 525
 526     gain = arg_to_scale (band->gain);
 527     omega = calculate_omega (band->freq, GST_AUDIO_FILTER (equ)->format.rate);
 528     bw = calculate_bw (band, GST_AUDIO_FILTER (equ)->format.rate);
 529     if (bw == 0.0)
 530       goto out;
 531
 532     egm = gain - 1.0;
 533     egp = gain + 1.0;
 534     alpha = tan (bw / 2.0);
 535
 536     delta = 2.0 * sqrt (gain) * alpha;
 537     b0 = egp + egm * cos (omega) + delta;
 538
 539     band->a0 = ((egp - egm * cos (omega) + delta) * gain) / b0;
 540     band->a1 = ((egm - egp * cos (omega)) * 2.0 * gain) / b0;
 541     band->a2 = ((egp - egm * cos (omega) - delta) * gain) / b0;
 542     band->b1 = ((egm + egp * cos (omega)) * 2.0) / b0;
 543     band->b2 = -((egp + egm * cos (omega) - delta)) / b0;
 544
 545
 546   out:
 547     GST_INFO
 548         ("gain = %5.1f, width= %7.2f, freq = %7.2f, a0 = %7.5g, a1 = %7.5g, a2=%7.5g b1 = %7.5g, b2 = %7.5g",
 549         band->gain, band->width, band->freq, band->a0, band->a1, band->a2,
 550         band->b1, band->b2);
 551   }
 552 }
 553
 554 static void
 555 setup_high_shelf_filter (GstIirEqualizer * equ, GstIirEqualizerBand * band)
 556 {
 557   g_return_if_fail (GST_AUDIO_FILTER (equ)->format.rate);
 558
 559   {
 560     gdouble gain, omega, bw;
 561     gdouble alpha, delta, b0;
 562     gdouble egp, egm;
 563
 564     gain = arg_to_scale (band->gain);
 565     omega = calculate_omega (band->freq, GST_AUDIO_FILTER (equ)->format.rate);
 566     bw = calculate_bw (band, GST_AUDIO_FILTER (equ)->format.rate);
 567     if (bw == 0.0)
 568       goto out;
 569
 570     egm = gain - 1.0;
 571     egp = gain + 1.0;
 572     alpha = tan (bw / 2.0);
 573
 574     delta = 2.0 * sqrt (gain) * alpha;
 575     b0 = egp - egm * cos (omega) + delta;
 576
 577     band->a0 = ((egp + egm * cos (omega) + delta) * gain) / b0;
 578     band->a1 = ((egm + egp * cos (omega)) * -2.0 * gain) / b0;
 579     band->a2 = ((egp + egm * cos (omega) - delta) * gain) / b0;
 580     band->b1 = ((egm - egp * cos (omega)) * -2.0) / b0;
 581     band->b2 = -((egp - egm * cos (omega) - delta)) / b0;
 582
 583
 584   out:
 585     GST_INFO
 586         ("gain = %5.1f, width= %7.2f, freq = %7.2f, a0 = %7.5g, a1 = %7.5g, a2=%7.5g b1 = %7.5g, b2 = %7.5g",
 587         band->gain, band->width, band->freq, band->a0, band->a1, band->a2,
 588         band->b1, band->b2);
 589   }
 590 }
 591
 592 /* Must be called with bands_lock and transform lock! */
 593 static void
 594 set_passthrough (GstIirEqualizer * equ)
 595 {
 596   gint i;
 597   gboolean passthrough = TRUE;
 598
 599   for (i = 0; i < equ->freq_band_count; i++) {
 600     passthrough = passthrough && (equ->bands[i]->gain == 0.0);
 601   }
 602
 603   gst_base_transform_set_passthrough (GST_BASE_TRANSFORM (equ), passthrough);
 604   GST_DEBUG ("Passthrough mode: %d\n", passthrough);
 605 }
 606
 607 /* Must be called with bands_lock and transform lock! */
 608 static void
 609 update_coefficients (GstIirEqualizer * equ)
 610 {
 611   gint i, n = equ->freq_band_count;
 612
 613   for (i = 0; i < n; i++) {
 614     if (equ->bands[i]->type == BAND_TYPE_PEAK)
 615       setup_peak_filter (equ, equ->bands[i]);
 616     else if (equ->bands[i]->type == BAND_TYPE_LOW_SHELF)
 617       setup_low_shelf_filter (equ, equ->bands[i]);
 618     else
 619       setup_high_shelf_filter (equ, equ->bands[i]);
 620   }
 621
 622   equ->need_new_coefficients = FALSE;
 623 }
 624
 625 /* Must be called with transform lock! */
 626 static void
 627 alloc_history (GstIirEqualizer * equ)
 628 {
 629   /* free + alloc = no memcpy */
 630   g_free (equ->history);
 631   equ->history =
 632       g_malloc0 (equ->history_size * GST_AUDIO_FILTER (equ)->format.channels *
 633       equ->freq_band_count);
 634 }
 635
 636 void
 637 gst_iir_equalizer_compute_frequencies (GstIirEqualizer * equ, guint new_count)
 638 {
 639   guint old_count, i;
 640   gdouble freq0, freq1, step;
 641   gchar name[20];
 642
 643   if (equ->freq_band_count == new_count)
 644     return;
 645
 646   BANDS_LOCK (equ);
 647
 648   if (G_UNLIKELY (equ->freq_band_count == new_count)) {
 649     BANDS_UNLOCK (equ);
 650     return;
 651   }
 652
 653   old_count = equ->freq_band_count;
 654   equ->freq_band_count = new_count;
 655   GST_DEBUG ("bands %u -> %u", old_count, new_count);
 656
 657   if (old_count < new_count) {
 658     /* add new bands */
 659     equ->bands = g_realloc (equ->bands, sizeof (GstObject *) * new_count);
 660     for (i = old_count; i < new_count; i++) {
 661       equ->bands[i] = g_object_new (GST_TYPE_IIR_EQUALIZER_BAND, NULL);
 662       /* otherwise they get names like 'iirequalizerband5' */
 663       sprintf (name, "band%u", i);
 664       gst_object_set_name (GST_OBJECT (equ->bands[i]), name);
 665       GST_DEBUG ("adding band[%d]=%p", i, equ->bands[i]);
 666
 667       gst_object_set_parent (GST_OBJECT (equ->bands[i]), GST_OBJECT (equ));
 668       gst_child_proxy_child_added (GST_OBJECT (equ),
 669           GST_OBJECT (equ->bands[i]));
 670     }
 671   } else {
 672     /* free unused bands */
 673     for (i = new_count; i < old_count; i++) {
 674       GST_DEBUG ("removing band[%d]=%p", i, equ->bands[i]);
 675       gst_child_proxy_child_removed (GST_OBJECT (equ),
 676           GST_OBJECT (equ->bands[i]));
 677       gst_object_unparent (GST_OBJECT (equ->bands[i]));
 678       equ->bands[i] = NULL;
 679     }
 680   }
 681
 682   alloc_history (equ);
 683
 684   /* set center frequencies and name band objects
 685    * FIXME: arg! we can't change the name of parented objects :(
 686    *   application should read band->freq to get the name
 687    */
 688
 689   step = pow (HIGHEST_FREQ / LOWEST_FREQ, 1.0 / new_count);
 690   freq0 = LOWEST_FREQ;
 691   for (i = 0; i < new_count; i++) {
 692     freq1 = freq0 * step;
 693
 694     if (i == 0)
 695       equ->bands[i]->type = BAND_TYPE_LOW_SHELF;
 696     else if (i == new_count - 1)
 697       equ->bands[i]->type = BAND_TYPE_HIGH_SHELF;
 698     else
 699       equ->bands[i]->type = BAND_TYPE_PEAK;
 700
 701     equ->bands[i]->freq = freq0 + ((freq1 - freq0) / 2.0);
 702     equ->bands[i]->width = freq1 - freq0;
 703     GST_DEBUG ("band[%2d] = '%lf'", i, equ->bands[i]->freq);
 704
 705     g_object_notify (G_OBJECT (equ->bands[i]), "bandwidth");
 706     g_object_notify (G_OBJECT (equ->bands[i]), "freq");
 707     g_object_notify (G_OBJECT (equ->bands[i]), "type");
 708
 709     /*
 710        if(equ->bands[i]->freq<10000.0)
 711        sprintf (name,"%dHz",(gint)equ->bands[i]->freq);
 712        else
 713        sprintf (name,"%dkHz",(gint)(equ->bands[i]->freq/1000.0));
 714        gst_object_set_name( GST_OBJECT (equ->bands[i]), name);
 715        GST_DEBUG ("band[%2d] = '%s'",i,name);
 716      */
 717     freq0 = freq1;
 718   }
 719
 720   equ->need_new_coefficients = TRUE;
 721   BANDS_UNLOCK (equ);
 722 }
 723
 724 /* start of code that is type specific */
 725
 726 #define CREATE_OPTIMIZED_FUNCTIONS_INT(TYPE,BIG_TYPE,MIN_VAL,MAX_VAL)   \
 727 typedef struct {                                                        \
 728   BIG_TYPE x1, x2;          /* history of input values for a filter */  \
 729   BIG_TYPE y1, y2;          /* history of output values for a filter */ \
 730 } SecondOrderHistory ## TYPE;                                           \
 731                                                                         \
 732 static inline BIG_TYPE                                                  \
 733 one_step_ ## TYPE (GstIirEqualizerBand *filter,                         \
 734     SecondOrderHistory ## TYPE *history, BIG_TYPE input)                \
 735 {                                                                       \
 736   /* calculate output */                                                \
 737   BIG_TYPE output = filter->a0 * input +                                \
 738       filter->a1 * history->x1 + filter->a2 * history->x2 +             \
 739       filter->b1 * history->y1 + filter->b2 * history->y2;              \
 740   /* update history */                                                  \
 741   history->y2 = history->y1;                                            \
 742   history->y1 = output;                                                 \
 743   history->x2 = history->x1;                                            \
 744   history->x1 = input;                                                  \
 745                                                                         \
 746   return output;                                                        \
 747 }                                                                       \
 748                                                                         \
 749 static const guint                                                      \
 750 history_size_ ## TYPE = sizeof (SecondOrderHistory ## TYPE);            \
 751                                                                         \
 752 static void                                                             \
 753 gst_iir_equ_process_ ## TYPE (GstIirEqualizer *equ, guint8 *data,       \
 754 guint size, guint channels)                                             \
 755 {                                                                       \
 756   guint frames = size / channels / sizeof (TYPE);                       \
 757   guint i, c, f, nf = equ->freq_band_count;                             \
 758   BIG_TYPE cur;                                                         \
 759   GstIirEqualizerBand **filters = equ->bands;                           \
 760                                                                         \
 761   for (i = 0; i < frames; i++) {                                        \
 762     SecondOrderHistory ## TYPE *history = equ->history;                 \
 763     for (c = 0; c < channels; c++) {                                    \
 764       cur = *((TYPE *) data);                                           \
 765       for (f = 0; f < nf; f++) {                                        \
 766         cur = one_step_ ## TYPE (filters[f], history, cur);             \
 767         history++;                                                      \
 768       }                                                                 \
 769       cur = CLAMP (cur, MIN_VAL, MAX_VAL);                              \
 770       *((TYPE *) data) = (TYPE) floor (cur);                            \
 771       data += sizeof (TYPE);                                            \
 772     }                                                                   \
 773   }                                                                     \
 774 }
 775
 776 #define CREATE_OPTIMIZED_FUNCTIONS(TYPE)                                \
 777 typedef struct {                                                        \
 778   TYPE x1, x2;          /* history of input values for a filter */  \
 779   TYPE y1, y2;          /* history of output values for a filter */ \
 780 } SecondOrderHistory ## TYPE;                                           \
 781                                                                         \
 782 static inline TYPE                                                      \
 783 one_step_ ## TYPE (GstIirEqualizerBand *filter,                         \
 784     SecondOrderHistory ## TYPE *history, TYPE input)                    \
 785 {                                                                       \
 786   /* calculate output */                                                \
 787   TYPE output = filter->a0 * input + filter->a1 * history->x1 +         \
 788       filter->a2 * history->x2 + filter->b1 * history->y1 +             \
 789       filter->b2 * history->y2;                                         \
 790   /* update history */                                                  \
 791   history->y2 = history->y1;                                            \
 792   history->y1 = output;                                                 \
 793   history->x2 = history->x1;                                            \
 794   history->x1 = input;                                                  \
 795                                                                         \
 796   return output;                                                        \
 797 }                                                                       \
 798                                                                         \
 799 static const guint                                                      \
 800 history_size_ ## TYPE = sizeof (SecondOrderHistory ## TYPE);            \
 801                                                                         \
 802 static void                                                             \
 803 gst_iir_equ_process_ ## TYPE (GstIirEqualizer *equ, guint8 *data,       \
 804 guint size, guint channels)                                             \
 805 {                                                                       \
 806   guint frames = size / channels / sizeof (TYPE);                       \
 807   guint i, c, f, nf = equ->freq_band_count;                             \
 808   TYPE cur;                                                             \
 809   GstIirEqualizerBand **filters = equ->bands;                           \
 810                                                                         \
 811   for (i = 0; i < frames; i++) {                                        \
 812     SecondOrderHistory ## TYPE *history = equ->history;                 \
 813     for (c = 0; c < channels; c++) {                                    \
 814       cur = *((TYPE *) data);                                           \
 815       for (f = 0; f < nf; f++) {                                        \
 816         cur = one_step_ ## TYPE (filters[f], history, cur);             \
 817         history++;                                                      \
 818       }                                                                 \
 819       *((TYPE *) data) = (TYPE) cur;                                    \
 820       data += sizeof (TYPE);                                            \
 821     }                                                                   \
 822   }                                                                     \
 823 }
 824
 825 CREATE_OPTIMIZED_FUNCTIONS_INT (gint16, gfloat, -32768.0, 32767.0);
 826 CREATE_OPTIMIZED_FUNCTIONS (gfloat);
 827 CREATE_OPTIMIZED_FUNCTIONS (gdouble);
 828
 829 static GstFlowReturn
 830 gst_iir_equalizer_transform_ip (GstBaseTransform * btrans, GstBuffer * buf)
 831 {
 832   GstAudioFilter *filter = GST_AUDIO_FILTER (btrans);
 833   GstIirEqualizer *equ = GST_IIR_EQUALIZER (btrans);
 834   GstClockTime timestamp;
 835
 836   if (G_UNLIKELY (filter->format.channels < 1 || equ->process == NULL))
 837     return GST_FLOW_NOT_NEGOTIATED;
 838
 839   BANDS_LOCK (equ);
 840   if (equ->need_new_coefficients) {
 841     update_coefficients (equ);
 842     set_passthrough (equ);
 843   }
 844   BANDS_UNLOCK (equ);
 845
 846   if (gst_base_transform_is_passthrough (btrans))
 847     return GST_FLOW_OK;
 848
 849   timestamp = GST_BUFFER_TIMESTAMP (buf);
 850   timestamp =
 851       gst_segment_to_stream_time (&btrans->segment, GST_FORMAT_TIME, timestamp);
 852
 853   if (GST_CLOCK_TIME_IS_VALID (timestamp))
 854     gst_object_sync_values (G_OBJECT (equ), timestamp);
 855
 856   equ->process (equ, GST_BUFFER_DATA (buf), GST_BUFFER_SIZE (buf),
 857       filter->format.channels);
 858
 859   return GST_FLOW_OK;
 860 }
 861
 862 static gboolean
 863 gst_iir_equalizer_setup (GstAudioFilter * audio, GstRingBufferSpec * fmt)
 864 {
 865   GstIirEqualizer *equ = GST_IIR_EQUALIZER (audio);
 866
 867   switch (fmt->type) {
 868     case GST_BUFTYPE_LINEAR:
 869       switch (fmt->width) {
 870         case 16:
 871           equ->history_size = history_size_gint16;
 872           equ->process = gst_iir_equ_process_gint16;
 873           break;
 874         default:
 875           return FALSE;
 876       }
 877       break;
 878     case GST_BUFTYPE_FLOAT:
 879       switch (fmt->width) {
 880         case 32:
 881           equ->history_size = history_size_gfloat;
 882           equ->process = gst_iir_equ_process_gfloat;
 883           break;
 884         case 64:
 885           equ->history_size = history_size_gdouble;
 886           equ->process = gst_iir_equ_process_gdouble;
 887           break;
 888         default:
 889           return FALSE;
 890       }
 891       break;
 892     default:
 893       return FALSE;
 894   }
 895
 896   alloc_history (equ);
 897   return TRUE;
 898 }
 899
 900
 901 static gboolean
 902 plugin_init (GstPlugin * plugin)
 903 {
 904   GST_DEBUG_CATEGORY_INIT (equalizer_debug, "equalizer", 0, "equalizer");
 905
 906   if (!(gst_element_register (plugin, "equalizer-nbands", GST_RANK_NONE,
 907               GST_TYPE_IIR_EQUALIZER_NBANDS)))
 908     return FALSE;
 909
 910   if (!(gst_element_register (plugin, "equalizer-3bands", GST_RANK_NONE,
 911               GST_TYPE_IIR_EQUALIZER_3BANDS)))
 912     return FALSE;
 913
 914   if (!(gst_element_register (plugin, "equalizer-10bands", GST_RANK_NONE,
 915               GST_TYPE_IIR_EQUALIZER_10BANDS)))
 916     return FALSE;
 917
 918   return TRUE;
 919 }
 920
 921 GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
 922     GST_VERSION_MINOR,
 923     "equalizer",
 924     "GStreamer audio equalizers",
 925     plugin_init, VERSION, GST_LICENSE, GST_PACKAGE_NAME, GST_PACKAGE_ORIGIN)