libs/ardour/amp.cc

   1 /*
   2     Copyright (C) 2006 Paul Davis
   3
   4     This program is free software; you can redistribute it and/or modify it
   5     under the terms of the GNU General Public License as published by the Free
   6     Software Foundation; either version 2 of the License, or (at your option)
   7     any later version.
   8
   9     This program is distributed in the hope that it will be useful, but WITHOUT
  10     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12     for more details.
  13
  14     You should have received a copy of the GNU General Public License along
  15     with this program; if not, write to the Free Software Foundation, Inc.,
  16     675 Mass Ave, Cambridge, MA 02139, USA.
  17 */
  18
  19 #include <iostream>
  20 #include <cstring>
  21 #include <cmath>
  22 #include <algorithm>
  23
  24 #include "evoral/Curve.hpp"
  25
  26 #include "ardour/amp.h"
  27 #include "ardour/audio_buffer.h"
  28 #include "ardour/buffer_set.h"
  29 #include "ardour/configuration.h"
  30 #include "ardour/io.h"
  31 #include "ardour/mute_master.h"
  32 #include "ardour/session.h"
  33
  34 #include "i18n.h"
  35
  36 using namespace ARDOUR;
  37
  38 Amp::Amp(Session& s, boost::shared_ptr<MuteMaster> mm)
  39         : Processor(s, "Amp")
  40         , _apply_gain(true)
  41         , _apply_gain_automation(false)
  42         , _current_gain(1.0)
  43         , _mute_master (mm)
  44 {
  45         boost::shared_ptr<AutomationList> gl(new AutomationList(Evoral::Parameter(GainAutomation)));
  46         _gain_control = boost::shared_ptr<GainControl>( new GainControl(X_("gaincontrol"), s, this, Evoral::Parameter(GainAutomation), gl ));
  47         add_control(_gain_control);
  48 }
  49
  50 bool
  51 Amp::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
  52 {
  53         out = in;
  54         return true;
  55 }
  56
  57 bool
  58 Amp::configure_io (ChanCount in, ChanCount out)
  59 {
  60         if (out != in) { // always 1:1
  61                 return false;
  62         }
  63
  64         return Processor::configure_io (in, out);
  65 }
  66
  67 void
  68 Amp::run (BufferSet& bufs, sframes_t start_frame, sframes_t end_frame, nframes_t nframes)
  69 {
  70         gain_t mute_gain;
  71
  72         if (_mute_master) {
  73                 mute_gain = _mute_master->mute_gain_at (MuteMaster::PreFader);
  74         } else {
  75                 mute_gain = 1.0;
  76         }
  77
  78         if (_apply_gain) {
  79
  80                 if (_apply_gain_automation) {
  81
  82                         gain_t* gab = _session.gain_automation_buffer ();
  83
  84                         if (mute_gain == 0.0) {
  85
  86                                 /* absolute mute */
  87
  88                                 if (_current_gain == 0.0) {
  89
  90                                         /* already silent */
  91
  92                                         for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
  93                                                 i->clear ();
  94                                         }
  95                                 } else {
  96
  97                                         /* cut to silence */
  98
  99                                         Amp::apply_gain (bufs, nframes, _current_gain, 0.0);
 100                                         _current_gain = 0.0;
 101                                 }
 102
 103
 104                         } else if (mute_gain != 1.0) {
 105
 106                                 /* mute dimming */
 107
 108                                 for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 109                                         Sample* const sp = i->data();
 110                                         for (nframes_t nx = 0; nx < nframes; ++nx) {
 111                                                 sp[nx] *= gab[nx] * mute_gain;
 112                                         }
 113                                 }
 114
 115                                 _current_gain = gab[nframes-1] * mute_gain;
 116
 117                         } else {
 118
 119                                 /* no mute */
 120
 121                                 for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 122                                         Sample* const sp = i->data();
 123                                         for (nframes_t nx = 0; nx < nframes; ++nx) {
 124                                                 sp[nx] *= gab[nx];
 125                                         }
 126                                 }
 127
 128                                 _current_gain = gab[nframes-1];
 129                         }
 130
 131
 132                 } else { /* manual (scalar) gain */
 133
 134                         gain_t dg = _gain_control->user_float() * mute_gain;
 135
 136                         if (_current_gain != dg) {
 137
 138                                 Amp::apply_gain (bufs, nframes, _current_gain, dg);
 139                                 _current_gain = dg;
 140
 141                         } else if (_current_gain != 1.0f) {
 142
 143                                 /* gain has not changed, but its non-unity
 144                                 */
 145
 146                                 for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 147                                         apply_gain_to_buffer (i->data(), nframes, _current_gain);
 148                                 }
 149                         }
 150                 }
 151         }
 152 }
 153
 154 void
 155 Amp::apply_gain (BufferSet& bufs, nframes_t nframes, gain_t initial, gain_t target)
 156 {
 157         /** Apply a (potentially) declicked gain to the audio buffers of @a bufs
 158          */
 159
 160         if (nframes == 0 || bufs.count().n_audio() == 0) {
 161                 return;
 162         }
 163
 164         // if we don't need to declick, defer to apply_simple_gain
 165         if (initial == target) {
 166                 apply_simple_gain (bufs, nframes, target);
 167                 return;
 168         }
 169
 170         const nframes_t declick = std::min ((nframes_t)128, nframes);
 171         gain_t         delta;
 172         double         fractional_shift = -1.0/declick;
 173         double         fractional_pos;
 174         gain_t         polscale = 1.0f;
 175
 176         if (target < initial) {
 177                 /* fade out: remove more and more of delta from initial */
 178                 delta = -(initial - target);
 179         } else {
 180                 /* fade in: add more and more of delta from initial */
 181                 delta = target - initial;
 182         }
 183
 184         for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 185                 Sample* const buffer = i->data();
 186
 187                 fractional_pos = 1.0;
 188
 189                 for (nframes_t nx = 0; nx < declick; ++nx) {
 190                         buffer[nx] *= polscale * (initial + (delta * (0.5 + 0.5 * cos (M_PI * fractional_pos))));
 191                         fractional_pos += fractional_shift;
 192                 }
 193
 194                 /* now ensure the rest of the buffer has the target value applied, if necessary. */
 195
 196                 if (declick != nframes) {
 197
 198                         if (target == 0.0) {
 199                                 memset (&buffer[declick], 0, sizeof (Sample) * (nframes - declick));
 200                         } else if (target != 1.0) {
 201                                 apply_gain_to_buffer (&buffer[declick], nframes - declick, target);
 202                         }
 203                 }
 204         }
 205 }
 206
 207 void
 208 Amp::apply_simple_gain (BufferSet& bufs, nframes_t nframes, gain_t target)
 209 {
 210         if (target == 0.0) {
 211                 for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 212                         memset (i->data(), 0, sizeof (Sample) * nframes);
 213                 }
 214         } else if (target != 1.0) {
 215                 for (BufferSet::audio_iterator i = bufs.audio_begin(); i != bufs.audio_end(); ++i) {
 216                         apply_gain_to_buffer (i->data(), nframes, target);
 217                 }
 218         }
 219 }
 220
 221 void
 222 Amp::inc_gain (gain_t factor, void *src)
 223 {
 224         float desired_gain = _gain_control->user_float();
 225         if (desired_gain == 0.0f) {
 226                 set_gain (0.000001f + (0.000001f * factor), src);
 227         } else {
 228                 set_gain (desired_gain + (desired_gain * factor), src);
 229         }
 230 }
 231
 232 void
 233 Amp::set_gain (gain_t val, void *src)
 234 {
 235         // max gain at about +6dB (10.0 ^ ( 6 dB * 0.05))
 236         if (val > 1.99526231f) {
 237                 val = 1.99526231f;
 238         }
 239
 240         //cerr << "set desired gain to " << val << " when curgain = " << _gain_control->get_value () << endl;
 241
 242         if (src != _gain_control.get()) {
 243                 _gain_control->set_value (val);
 244                 // bit twisty, this will come back and call us again
 245                 // (this keeps control in sync with reality)
 246                 return;
 247         }
 248
 249         _gain_control->set_float(val, false);
 250         _session.set_dirty();
 251 }
 252
 253 XMLNode&
 254 Amp::state (bool full_state)
 255 {
 256         XMLNode& node (Processor::state (full_state));
 257         node.add_property("type", "amp");
 258         return node;
 259 }
 260
 261 void
 262 Amp::GainControl::set_value (float val)
 263 {
 264         // max gain at about +6dB (10.0 ^ ( 6 dB * 0.05))
 265         if (val > 1.99526231f)
 266                 val = 1.99526231f;
 267
 268         _amp->set_gain (val, this);
 269
 270         AutomationControl::set_value(val);
 271 }
 272
 273 float
 274 Amp::GainControl::get_value (void) const
 275 {
 276         return AutomationControl::get_value();
 277 }
 278
 279 void
 280 Amp::setup_gain_automation (sframes_t start_frame, sframes_t end_frame, nframes_t nframes)
 281 {
 282         Glib::Mutex::Lock am (data().control_lock(), Glib::TRY_LOCK);
 283
 284         if (am.locked() && _session.transport_rolling() && _gain_control->automation_playback()) {
 285                 _apply_gain_automation = _gain_control->list()->curve().rt_safe_get_vector (
 286                         start_frame, end_frame, _session.gain_automation_buffer(), nframes);
 287         } else {
 288                 _apply_gain_automation = false;
 289         }
 290 }