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         // cerr << "meter " << name() << " runs with " << bufs.available() << " inputs\n";
  49
  50         const uint32_t n_audio = min (current_meters.n_audio(), bufs.count().n_audio());
  51         const uint32_t n_midi  = min (current_meters.n_midi(), bufs.count().n_midi());
  52
  53         uint32_t n = 0;
  54
  55         // Meter MIDI in to the first n_midi peaks
  56         for (uint32_t i = 0; i < n_midi; ++i, ++n) {
  57                 float val = 0.0f;
  58                 for (MidiBuffer::iterator e = bufs.get_midi(i).begin(); e != bufs.get_midi(i).end(); ++e) {
  59                         const Evoral::MIDIEvent<framepos_t> ev(*e, false);
  60                         if (ev.is_note_on()) {
  61                                 const float this_vel = log(ev.buffer()[2] / 127.0 * (M_E*M_E-M_E) + M_E) - 1.0;
  62                                 if (this_vel > val) {
  63                                         val = this_vel;
  64                                 }
  65                         } else {
  66                                 val += 1.0 / bufs.get_midi(n).capacity();
  67                                 if (val > 1.0) {
  68                                         val = 1.0;
  69                                 }
  70                         }
  71                 }
  72                 _peak_power[n] = max (val, _peak_power[n]);
  73         }
  74
  75         // Meter audio in to the rest of the peaks
  76         for (uint32_t i = 0; i < n_audio; ++i, ++n) {
  77                 _peak_power[n] = compute_peak (bufs.get_audio(i).data(), nframes, _peak_power[n]);
  78         }
  79
  80         // Zero any excess peaks
  81         for (uint32_t i = n; i < _peak_power.size(); ++i) {
  82                 _peak_power[i] = 0.0f;
  83         }
  84
  85         _active = _pending_active;
  86 }
  87
  88 void
  89 PeakMeter::reset ()
  90 {
  91         for (size_t i = 0; i < _peak_power.size(); ++i) {
  92                 _peak_power[i] = 0.0f;
  93         }
  94 }
  95
  96 void
  97 PeakMeter::reset_max ()
  98 {
  99         for (size_t i = 0; i < _max_peak_power.size(); ++i) {
 100                 _max_peak_power[i] = -INFINITY;
 101         }
 102 }
 103
 104 bool
 105 PeakMeter::can_support_io_configuration (const ChanCount& in, ChanCount& out) const
 106 {
 107         out = in;
 108         return true;
 109 }
 110
 111 bool
 112 PeakMeter::configure_io (ChanCount in, ChanCount out)
 113 {
 114         if (out != in) { // always 1:1
 115                 return false;
 116         }
 117
 118         current_meters = in;
 119
 120         reset_max_channels (in);
 121
 122         return Processor::configure_io (in, out);
 123 }
 124
 125 void
 126 PeakMeter::reflect_inputs (const ChanCount& in)
 127 {
 128         current_meters = in;
 129
 130         ConfigurationChanged (in, in); /* EMIT SIGNAL */
 131 }
 132
 133 void
 134 PeakMeter::reset_max_channels (const ChanCount& chn)
 135 {
 136         uint32_t const limit = chn.n_total();
 137
 138         while (_peak_power.size() > limit) {
 139                 _peak_power.pop_back();
 140                 _visible_peak_power.pop_back();
 141                 _max_peak_power.pop_back();
 142         }
 143
 144         while (_peak_power.size() < limit) {
 145                 _peak_power.push_back(0);
 146                 _visible_peak_power.push_back(minus_infinity());
 147                 _max_peak_power.push_back(minus_infinity());
 148         }
 149
 150         assert(_peak_power.size() == limit);
 151         assert(_visible_peak_power.size() == limit);
 152         assert(_max_peak_power.size() == limit);
 153 }
 154
 155 /** To be driven by the Meter signal from IO.
 156  * Caller MUST hold its own processor_lock to prevent reconfiguration
 157  * of meter size during this call.
 158  */
 159
 160 void
 161 PeakMeter::meter ()
 162 {
 163         if (!_active) {
 164                 return;
 165         }
 166
 167         assert(_visible_peak_power.size() == _peak_power.size());
 168
 169         const size_t limit = min (_peak_power.size(), (size_t) current_meters.n_total ());
 170
 171         for (size_t n = 0; n < limit; ++n) {
 172
 173                 /* grab peak since last read */
 174
 175                 float new_peak = _peak_power[n]; /* XXX we should use atomic exchange from here ... */
 176                 _peak_power[n] = 0;              /* ... to here */
 177
 178                 /* compute new visible value using falloff */
 179
 180                 if (new_peak > 0.0) {
 181                         new_peak = fast_coefficient_to_dB (new_peak);
 182                 } else {
 183                         new_peak = minus_infinity();
 184                 }
 185
 186                 /* update max peak */
 187
 188                 _max_peak_power[n] = std::max (new_peak, _max_peak_power[n]);
 189
 190                 if (Config->get_meter_falloff() == 0.0f || new_peak > _visible_peak_power[n]) {
 191                         _visible_peak_power[n] = new_peak;
 192                 } else {
 193                         // do falloff
 194                         new_peak = _visible_peak_power[n] - (Config->get_meter_falloff() * 0.01f);
 195                         _visible_peak_power[n] = std::max (new_peak, -INFINITY);
 196                 }
 197         }
 198 }
 199
 200 XMLNode&
 201 PeakMeter::state (bool full_state)
 202 {
 203         XMLNode& node (Processor::state (full_state));
 204         node.add_property("type", "meter");
 205         return node;
 206 }
 207
 208