compressor.c

   1 /*
   2 Calf Box, an open source musical instrument.
   3 Copyright (C) 2010-2011 Krzysztof Foltman
   4
   5 This program is free software: you can redistribute it and/or modify
   6 it under the terms of the GNU General Public License as published by
   7 the Free Software Foundation, either version 3 of the License, or
   8 (at your option) any later version.
   9
  10 This program is distributed in the hope that it will be useful,
  11 but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 GNU General Public License for more details.
  14
  15 You should have received a copy of the GNU General Public License
  16 along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 */
  18
  19 #include "config.h"
  20 #include "config-api.h"
  21 #include "dspmath.h"
  22 #include "module.h"
  23 #include "onepole-float.h"
  24 #include <glib.h>
  25 #include <malloc.h>
  26 #include <math.h>
  27 #include <memory.h>
  28 #include <sndfile.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31
  32 #define MODULE_PARAMS compressor_params
  33
  34 struct compressor_params
  35 {
  36     float threshold;
  37     float ratio;
  38     float attack;
  39     float release;
  40     float makeup;
  41 };
  42
  43 struct compressor_module
  44 {
  45     struct cbox_module module;
  46
  47     struct compressor_params *params, *old_params;
  48     struct cbox_onepolef_coeffs attack_lp, release_lp, fast_attack_lp;
  49     struct cbox_onepolef_state tracker;
  50     struct cbox_onepolef_state tracker2;
  51 };
  52
  53 MODULE_PROCESSCMD_FUNCTION(compressor)
  54 {
  55     struct compressor_module *m = (struct compressor_module *)ct->user_data;
  56
  57     EFFECT_PARAM("/makeup", "f", makeup, double, dB2gain_simple, -100, 100) else
  58     EFFECT_PARAM("/threshold", "f", threshold, double, dB2gain_simple, -100, 100) else
  59     EFFECT_PARAM("/ratio", "f", ratio, double, , 1, 100) else
  60     EFFECT_PARAM("/attack", "f", attack, double, , 1, 1000) else
  61     EFFECT_PARAM("/release", "f", release, double, , 1, 1000) else
  62     if (!strcmp(cmd->command, "/status") && !strcmp(cmd->arg_types, ""))
  63     {
  64         if (!cbox_check_fb_channel(fb, cmd->command, error))
  65             return FALSE;
  66         return cbox_execute_on(fb, NULL, "/makeup", "f", error, gain2dB_simple(m->params->makeup))
  67             && cbox_execute_on(fb, NULL, "/threshold", "f", error, gain2dB_simple(m->params->threshold))
  68             && cbox_execute_on(fb, NULL, "/ratio", "f", error, m->params->ratio)
  69             && cbox_execute_on(fb, NULL, "/attack", "f", error, m->params->attack)
  70             && cbox_execute_on(fb, NULL, "/release", "f", error, m->params->release)
  71             && CBOX_OBJECT_DEFAULT_STATUS(&m->module, fb, error)
  72             ;
  73     }
  74     else
  75         return cbox_object_default_process_cmd(ct, fb, cmd, error);
  76     return TRUE;
  77 }
  78
  79 void compressor_process_event(struct cbox_module *module, const uint8_t *data, uint32_t len)
  80 {
  81     // struct compressor_module *m = module->user_data;
  82 }
  83
  84 void compressor_process_block(struct cbox_module *module, cbox_sample_t **inputs, cbox_sample_t **outputs)
  85 {
  86     struct compressor_module *m = module->user_data;
  87
  88     if (m->params != m->old_params)
  89     {
  90         float scale = M_PI * 1000 / m->module.srate;
  91         cbox_onepolef_set_lowpass(&m->fast_attack_lp, 2 * scale / m->params->attack);
  92         cbox_onepolef_set_lowpass(&m->attack_lp, scale / m->params->attack);
  93         cbox_onepolef_set_lowpass(&m->release_lp, scale / m->params->release);
  94         m->old_params = m->params;
  95     }
  96
  97     float threshold = m->params->threshold, invratio = 1.0 / m->params->ratio;
  98     for (int i = 0; i < CBOX_BLOCK_SIZE; i++)
  99     {
 100         float left = inputs[0][i], right = inputs[1][i];
 101         float sig = 0.5 * (fabs(left) > fabs(right) ? fabs(left) : fabs(right));
 102
 103         int falling = sig < m->tracker.y1 && sig < m->tracker.x1;
 104         int rising_fast = sig > 4 * m->tracker.y1 && sig > 4 * m->tracker.x1;
 105         sig = cbox_onepolef_process_sample(&m->tracker, falling ? &m->release_lp : (rising_fast * m->tracker.y1 ? &m->fast_attack_lp : &m->attack_lp), sig);
 106         sig = cbox_onepolef_process_sample(&m->tracker2, falling ? &m->release_lp : (rising_fast * m->tracker2.y1 ? &m->fast_attack_lp : &m->attack_lp), sig);
 107         float gain = 1.0;
 108         if (sig > threshold)
 109             gain = threshold * powf(sig / threshold, invratio) / sig;
 110         gain *= m->params->makeup;
 111
 112         outputs[0][i] = left * gain;
 113         outputs[1][i] = right * gain;
 114     }
 115 }
 116
 117 MODULE_SIMPLE_DESTROY_FUNCTION(compressor)
 118
 119 MODULE_CREATE_FUNCTION(compressor)
 120 {
 121     static int inited = 0;
 122     if (!inited)
 123     {
 124         inited = 1;
 125     }
 126
 127     struct compressor_module *m = malloc(sizeof(struct compressor_module));
 128     CALL_MODULE_INIT(m, 2, 2, compressor);
 129     m->module.process_event = compressor_process_event;
 130     m->module.process_block = compressor_process_block;
 131
 132     struct compressor_params *p = malloc(sizeof(struct compressor_params));
 133     p->threshold = cbox_config_get_gain_db(cfg_section, "threshold", -12.0);
 134     p->ratio = cbox_config_get_float(cfg_section, "ratio", 2.0);
 135     p->attack = cbox_config_get_float(cfg_section, "attack", 5.0);
 136     p->release = cbox_config_get_float(cfg_section, "release", 100.0);
 137     p->makeup = cbox_config_get_gain_db(cfg_section, "makeup", 6.0);
 138     m->params = p;
 139     m->old_params = NULL;
 140
 141     cbox_onepolef_reset(&m->tracker);
 142     cbox_onepolef_reset(&m->tracker2);
 143
 144     return &m->module;
 145 }
 146
 147
 148 struct cbox_module_keyrange_metadata compressor_keyranges[] = {
 149 };
 150
 151 struct cbox_module_livecontroller_metadata compressor_controllers[] = {
 152 };
 153
 154 DEFINE_MODULE(compressor, 2, 2)
 155