libs/ardour/meter.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 "ardour/meter.h"
  20 #include <algorithm>
  21 #include <cmath>
  22 #include "ardour/buffer_set.h"
  23 #include "ardour/peak.h"
  24 #include "ardour/dB.h"
  25 #include "ardour/session.h"
  26 #include "ardour/midi_buffer.h"
  27 #include "ardour/audio_buffer.h"
  28 #include "ardour/runtime_functions.h"
  29
  30 using namespace std;
  31
  32 using namespace ARDOUR;
  33
  34 PBD::Signal0<void> Metering::Meter;
  35
  36 /** Get peaks from @a bufs
  37  * Input acceptance is lenient - the first n buffers from @a bufs will
  38  * be metered, where n was set by the last call to setup(), excess meters will
  39  * be set to 0.
  40  */
  41 void
  42 PeakMeter::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/, pframes_t nframes, bool)
  43 {
  44         if (!_active && !_pending_active) {
  45                 return;
  46         }
  47
  48         const uint32_t n_audio = min(_configured_input.n_audio(), bufs.count().n_audio());
  49         const uint32_t n_midi  = min(_configured_input.n_midi(), bufs.count().n_midi());
  50
  51         uint32_t n = 0;
  52
  53         // Meter MIDI in to the first n_midi peaks
  54         for (uint32_t i = 0; i < n_midi; ++i, ++n) {
  55                 float val = 0.0f;
  56                 for (MidiBuffer::iterator e = bufs.get_midi(i).begin(); e != bufs.get_midi(i).end(); ++e) {
  57                         const Evoral::MIDIEvent<framepos_t> ev(*e, false);
  58                         if (ev.is_note_on()) {
  59                                 const float this_vel = log(ev.buffer()[2] / 127.0 * (M_E*M_E-M_E) + M_E) - 1.0;
  60                                 if (this_vel > val) {
  61                                         val = this_vel;
  62                                 }
  63                         } else {
  64                                 val += 1.0 / bufs.get_midi(n).capacity();
  65                                 if (val > 1.0) {
  66                                         val = 1.0;
  67                                 }
  68                         }
  69                 }
  70                 _peak_power[n] = max (val, _peak_power[n]);
  71         }
  72
  73         // Meter audio in to the rest of the peaks
  74         for (uint32_t i = 0; i < n_audio; ++i, ++n) {
  75                 _peak_power[n] = compute_peak (bufs.get_audio(i).data(), nframes, _peak_power[n]);
  76         }
  77
  78         // Zero any excess peaks
  79         for (uint32_t i = n; i < _peak_power.size(); ++i) {
  80                 _peak_power[i] = 0.0f;
  81         }
  82
  83         _active = _pending_active;
  84 }
  85
  86 void
  87 PeakMeter::reset ()
  88 {
  89         for (size_t i = 0; i < _peak_power.size(); ++i) {
  90                 _peak_power[i] = 0.0f;
  91         }
  92 }
  93
  94 void
  95 PeakMeter::reset_max ()
  96 {
  97         for (size_t i = 0; i < _max_peak_power.size(); ++i) {
  98                 _max_peak_power[i] = -INFINITY;
  99         }
 100 }
 101
 102 bool
 103 PeakMeter::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
 104 {
 105         out = in;
 106         return true;
 107 }
 108
 109 bool
 110 PeakMeter::configure_io (ChanCount in, ChanCount out)
 111 {
 112         if (out != in) { // always 1:1
 113                 return false;
 114         }
 115
 116         current_meters = in;
 117
 118         reset_max_channels (in);
 119
 120         return Processor::configure_io (in, out);
 121 }
 122
 123 void
 124 PeakMeter::reflect_inputs (const ChanCount& in)
 125 {
 126         current_meters = in;
 127 }
 128
 129 void
 130 PeakMeter::reset_max_channels (const ChanCount& chn)
 131 {
 132         uint32_t limit = chn.n_total();
 133
 134         while (_peak_power.size() > limit) {
 135                 _peak_power.pop_back();
 136                 _visible_peak_power.pop_back();
 137                 _max_peak_power.pop_back();
 138         }
 139
 140         while (_peak_power.size() < limit) {
 141                 _peak_power.push_back(0);
 142                 _visible_peak_power.push_back(minus_infinity());
 143                 _max_peak_power.push_back(minus_infinity());
 144         }
 145
 146         assert(_peak_power.size() == limit);
 147         assert(_visible_peak_power.size() == limit);
 148         assert(_max_peak_power.size() == limit);
 149 }
 150
 151 /** To be driven by the Meter signal from IO.
 152  * Caller MUST hold its own processor_lock to prevent reconfiguration
 153  * of meter size during this call.
 154  */
 155
 156 void
 157 PeakMeter::meter ()
 158 {
 159         if (!_active) {
 160                 return;
 161         }
 162
 163         assert(_visible_peak_power.size() == _peak_power.size());
 164
 165         const size_t limit = min (_peak_power.size(), (size_t) current_meters.n_total ());
 166
 167         for (size_t n = 0; n < limit; ++n) {
 168
 169                 /* grab peak since last read */
 170
 171                 float new_peak = _peak_power[n]; /* XXX we should use atomic exchange from here ... */
 172                 _peak_power[n] = 0;              /* ... to here */
 173
 174                 /* compute new visible value using falloff */
 175
 176                 if (new_peak > 0.0) {
 177                         new_peak = fast_coefficient_to_dB (new_peak);
 178                 } else {
 179                         new_peak = minus_infinity();
 180                 }
 181
 182                 /* update max peak */
 183
 184                 _max_peak_power[n] = std::max (new_peak, _max_peak_power[n]);
 185
 186                 if (Config->get_meter_falloff() == 0.0f || new_peak > _visible_peak_power[n]) {
 187                         _visible_peak_power[n] = new_peak;
 188                 } else {
 189                         // do falloff
 190                         new_peak = _visible_peak_power[n] - (Config->get_meter_falloff() * 0.01f);
 191                         _visible_peak_power[n] = std::max (new_peak, -INFINITY);
 192                 }
 193         }
 194 }
 195
 196 XMLNode&
 197 PeakMeter::state (bool full_state)
 198 {
 199         XMLNode& node (Processor::state (full_state));
 200         node.add_property("type", "meter");
 201         return node;
 202 }
 203
 204