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 <algorithm>
  20 #include <cmath>
  21
  22 #include "pbd/compose.h"
  23
  24 #include "ardour/audio_buffer.h"
  25 #include "ardour/buffer_set.h"
  26 #include "ardour/dB.h"
  27 #include "ardour/meter.h"
  28 #include "ardour/midi_buffer.h"
  29 #include "ardour/rc_configuration.h"
  30 #include "ardour/runtime_functions.h"
  31
  32 using namespace std;
  33
  34 using namespace ARDOUR;
  35
  36 PBD::Signal0<void> Metering::Meter;
  37
  38 PeakMeter::PeakMeter (Session& s, const std::string& name)
  39     : Processor (s, string_compose ("meter-%1", name))
  40 {
  41 }
  42
  43
  44 /** Get peaks from @a bufs
  45  * Input acceptance is lenient - the first n buffers from @a bufs will
  46  * be metered, where n was set by the last call to setup(), excess meters will
  47  * be set to 0.
  48  */
  49 void
  50 PeakMeter::run (BufferSet& bufs, framepos_t /*start_frame*/, framepos_t /*end_frame*/, pframes_t nframes, bool)
  51 {
  52         if (!_active && !_pending_active) {
  53                 return;
  54         }
  55
  56         // cerr << "meter " << name() << " runs with " << bufs.available() << " inputs\n";
  57
  58         const uint32_t n_audio = min (current_meters.n_audio(), bufs.count().n_audio());
  59         const uint32_t n_midi  = min (current_meters.n_midi(), bufs.count().n_midi());
  60
  61         uint32_t n = 0;
  62
  63         // Meter MIDI in to the first n_midi peaks
  64         for (uint32_t i = 0; i < n_midi; ++i, ++n) {
  65                 float val = 0.0f;
  66                 MidiBuffer& buf (bufs.get_midi(i));
  67
  68                 for (MidiBuffer::iterator e = buf.begin(); e != buf.end(); ++e) {
  69                         const Evoral::MIDIEvent<framepos_t> ev(*e, false);
  70                         if (ev.is_note_on()) {
  71                                 const float this_vel = log(ev.buffer()[2] / 127.0 * (M_E*M_E-M_E) + M_E) - 1.0;
  72                                 if (this_vel > val) {
  73                                         val = this_vel;
  74                                 }
  75                         } else {
  76                                 val += 1.0 / bufs.get_midi(n).capacity();
  77                                 if (val > 1.0) {
  78                                         val = 1.0;
  79                                 }
  80                         }
  81                 }
  82                 _peak_power[n] = max (val, _peak_power[n]);
  83         }
  84
  85         // Meter audio in to the rest of the peaks
  86         for (uint32_t i = 0; i < n_audio; ++i, ++n) {
  87                 _peak_power[n] = compute_peak (bufs.get_audio(i).data(), nframes, _peak_power[n]);
  88         }
  89
  90         // Zero any excess peaks
  91         for (uint32_t i = n; i < _peak_power.size(); ++i) {
  92                 _peak_power[i] = 0.0f;
  93         }
  94
  95         _active = _pending_active;
  96 }
  97
  98 void
  99 PeakMeter::reset ()
 100 {
 101         for (size_t i = 0; i < _peak_power.size(); ++i) {
 102                 _peak_power[i] = 0.0f;
 103         }
 104 }
 105
 106 void
 107 PeakMeter::reset_max ()
 108 {
 109         for (size_t i = 0; i < _max_peak_power.size(); ++i) {
 110                 _max_peak_power[i] = -INFINITY;
 111         }
 112 }
 113
 114 bool
 115 PeakMeter::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
 116 {
 117         out = in;
 118         return true;
 119 }
 120
 121 bool
 122 PeakMeter::configure_io (ChanCount in, ChanCount out)
 123 {
 124         if (out != in) { // always 1:1
 125                 return false;
 126         }
 127
 128         current_meters = in;
 129
 130         reset_max_channels (in);
 131
 132         return Processor::configure_io (in, out);
 133 }
 134
 135 void
 136 PeakMeter::reflect_inputs (const ChanCount& in)
 137 {
 138         current_meters = in;
 139
 140         ConfigurationChanged (in, in); /* EMIT SIGNAL */
 141 }
 142
 143 void
 144 PeakMeter::reset_max_channels (const ChanCount& chn)
 145 {
 146         uint32_t const limit = chn.n_total();
 147
 148         while (_peak_power.size() > limit) {
 149                 _peak_power.pop_back();
 150                 _visible_peak_power.pop_back();
 151                 _max_peak_power.pop_back();
 152         }
 153
 154         while (_peak_power.size() < limit) {
 155                 _peak_power.push_back(0);
 156                 _visible_peak_power.push_back(minus_infinity());
 157                 _max_peak_power.push_back(minus_infinity());
 158         }
 159
 160         assert(_peak_power.size() == limit);
 161         assert(_visible_peak_power.size() == limit);
 162         assert(_max_peak_power.size() == limit);
 163 }
 164
 165 /** To be driven by the Meter signal from IO.
 166  * Caller MUST hold its own processor_lock to prevent reconfiguration
 167  * of meter size during this call.
 168  */
 169
 170 void
 171 PeakMeter::meter ()
 172 {
 173         if (!_active) {
 174                 return;
 175         }
 176
 177         assert(_visible_peak_power.size() == _peak_power.size());
 178
 179         const size_t limit = min (_peak_power.size(), (size_t) current_meters.n_total ());
 180
 181         for (size_t n = 0; n < limit; ++n) {
 182
 183                 /* grab peak since last read */
 184
 185                 float new_peak = _peak_power[n]; /* XXX we should use atomic exchange from here ... */
 186                 _peak_power[n] = 0;              /* ... to here */
 187
 188                 /* compute new visible value using falloff */
 189
 190                 if (new_peak > 0.0) {
 191                         new_peak = fast_coefficient_to_dB (new_peak);
 192                 } else {
 193                         new_peak = minus_infinity();
 194                 }
 195
 196                 /* update max peak */
 197
 198                 _max_peak_power[n] = std::max (new_peak, _max_peak_power[n]);
 199
 200                 if (Config->get_meter_falloff() == 0.0f || new_peak > _visible_peak_power[n]) {
 201                         _visible_peak_power[n] = new_peak;
 202                 } else {
 203                         // do falloff
 204                         new_peak = _visible_peak_power[n] - (Config->get_meter_falloff() * 0.01f);
 205                         _visible_peak_power[n] = std::max (new_peak, -INFINITY);
 206                 }
 207         }
 208 }
 209
 210 XMLNode&
 211 PeakMeter::state (bool full_state)
 212 {
 213         XMLNode& node (Processor::state (full_state));
 214         node.add_property("type", "meter");
 215         return node;
 216 }
 217
 218