2 * Copyright (C) 2008-2013 Hans Baier <hansfbaier@googlemail.com>
3 * Copyright (C) 2009-2010 Carl Hetherington <carl@carlh.net>
4 * Copyright (C) 2009-2012 David Robillard <d@drobilla.net>
5 * Copyright (C) 2009-2019 Paul Davis <paul@linuxaudiosystems.com>
6 * Copyright (C) 2012-2013 Robin Gareus <robin@gareus.org>
7 * Copyright (C) 2013-2018 John Emmas <john@creativepost.co.uk>
8 * Copyright (C) 2015-2016 Nick Mainsbridge <mainsbridge@gmail.com>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License along
21 * with this program; if not, write to the Free Software Foundation, Inc.,
22 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include <sys/types.h>
29 #include "pbd/error.h"
30 #include "pbd/failed_constructor.h"
31 #include "pbd/pthread_utils.h"
32 #include "pbd/convert.h"
34 #include "midi++/port.h"
36 #include "ardour/audioengine.h"
37 #include "ardour/debug.h"
38 #include "ardour/midi_buffer.h"
39 #include "ardour/midi_port.h"
40 #include "ardour/session.h"
41 #include "ardour/tempo.h"
42 #include "ardour/transport_master.h"
43 #include "ardour/transport_master_manager.h"
48 using namespace ARDOUR;
52 #define ENGINE AudioEngine::instance()
54 MIDIClock_TransportMaster::MIDIClock_TransportMaster (std::string const & name, int ppqn)
55 : TransportMaster (MIDIClock, name)
57 , midi_clock_count (0)
63 MIDIClock_TransportMaster::~MIDIClock_TransportMaster()
65 port_connections.drop_connections ();
69 MIDIClock_TransportMaster::init ()
76 MIDIClock_TransportMaster::create_port ()
78 if ((_port = create_midi_port (string_compose ("%1 in", _name))) == 0) {
79 throw failed_constructor();
84 MIDIClock_TransportMaster::set_session (Session *session)
86 port_connections.drop_connections();
89 /* only connect to signals if we have a proxy, because otherwise we
90 * cannot interpet incoming data (no tempo map etc.)
94 parser.timing.connect_same_thread (port_connections, boost::bind (&MIDIClock_TransportMaster::update_midi_clock, this, _1, _2));
95 parser.start.connect_same_thread (port_connections, boost::bind (&MIDIClock_TransportMaster::start, this, _1, _2));
96 parser.contineu.connect_same_thread (port_connections, boost::bind (&MIDIClock_TransportMaster::contineu, this, _1, _2));
97 parser.stop.connect_same_thread (port_connections, boost::bind (&MIDIClock_TransportMaster::stop, this, _1, _2));
98 parser.position.connect_same_thread (port_connections, boost::bind (&MIDIClock_TransportMaster::position, this, _1, _2, _3, _4));
105 MIDIClock_TransportMaster::pre_process (MIDI::pframes_t nframes, samplepos_t now, boost::optional<samplepos_t> session_pos)
107 /* Read and parse incoming MIDI */
109 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("preprocess with lt = %1 @ %2, running ? %3\n", current.timestamp, now, _running));
111 _midi_port->read_and_parse_entire_midi_buffer_with_no_speed_adjustment (nframes, parser, now);
113 /* no clock messages ever, or no clock messages for 1/4 second ? conclude that its stopped */
115 if (!current.timestamp || (now > current.timestamp && ((now - current.timestamp) > (ENGINE->sample_rate() / 4)))) {
119 midi_clock_count = 0;
121 DEBUG_TRACE (DEBUG::MidiClock, "No MIDI Clock messages received for some time, stopping!\n");
126 const samplepos_t current_pos = current.position + ((now - current.timestamp) * current.speed);
127 _current_delta = current_pos - *session_pos;
132 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("speed_and_position: speed %1 should-be %2 transport %3 \n", current.speed, current.position, _session->transport_sample()));
136 MIDIClock_TransportMaster::calculate_one_ppqn_in_samples_at(samplepos_t time)
138 const double samples_per_quarter_note = _session->tempo_map().samples_per_quarter_note_at (time, ENGINE->sample_rate());
140 one_ppqn_in_samples = samples_per_quarter_note / double (ppqn);
141 // DEBUG_TRACE (DEBUG::MidiClock, string_compose ("at %1, one ppqn = %2\n", time, one_ppqn_in_samples));
145 MIDIClock_TransportMaster::calculate_song_position(uint16_t song_position_in_sixteenth_notes)
147 samplepos_t song_position_samples = 0;
148 for (uint16_t i = 1; i <= song_position_in_sixteenth_notes; ++i) {
149 // one quarter note contains ppqn pulses, so a sixteenth note is ppqn / 4 pulses
150 calculate_one_ppqn_in_samples_at(song_position_samples);
151 song_position_samples += one_ppqn_in_samples * (samplepos_t)(ppqn / 4);
154 return song_position_samples;
158 MIDIClock_TransportMaster::calculate_filter_coefficients (double qpm)
160 /* Paul says: I don't understand this computation of bandwidth
163 const double bandwidth = 2.0 / qpm;
165 /* Frequency of the clock messages is ENGINE->sample_rate() / * one_ppqn_in_samples, per second or in Hz */
166 const double freq = (double) ENGINE->sample_rate() / one_ppqn_in_samples;
168 const double omega = 2.0 * M_PI * bandwidth / freq;
169 b = 1.4142135623730950488 * omega; // sqrt (2.0) * omega
172 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("DLL coefficients: bw:%1 omega:%2 b:%3 c:%4\n", bandwidth, omega, b, c));
176 MIDIClock_TransportMaster::update_midi_clock (Parser& /*parser*/, samplepos_t timestamp)
178 samplepos_t elapsed_since_start = timestamp - first_timestamp;
181 calculate_one_ppqn_in_samples_at (current.position);
183 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("clock count %1, sbp %2\n", midi_clock_count, current.position));
185 if (midi_clock_count == 0) {
186 /* second 0xf8 message after start/reset has arrived */
188 first_timestamp = timestamp;
189 current.update (0, timestamp, 0);
191 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("first clock message after start received @ %1\n", timestamp));
195 current.position += one_ppqn_in_samples;
197 } else if (midi_clock_count == 1) {
199 /* second 0xf8 message has arrived. we can now estimate QPM
200 * (quarters per minute, and fully initialize the DLL
203 e = timestamp - current.timestamp;
205 const samplecnt_t samples_per_quarter = e * 24;
206 _bpm = (ENGINE->sample_rate() * 60.0) / samples_per_quarter;
208 calculate_filter_coefficients (_bpm);
210 /* finish DLL initialization */
214 t1 = t0 + e2; /* timestamp we predict for the next 0xf8 clock message */
217 current.update (one_ppqn_in_samples, timestamp, 0);
221 /* 3rd or later MIDI clock message. We can now compute actual
222 * speed (and tempo) with the DLL
225 e = timestamp - t1; // error between actual time of arrival of clock message and our predicted time
230 const double samples_per_quarter = (timestamp - current.timestamp) * 24.0;
231 const double instantaneous_bpm = (ENGINE->sample_rate() * 60.0) / samples_per_quarter;
233 const double predicted_clock_interval_in_samples = (t1 - t0);
235 /* _speed is relative to session tempo map */
237 double speed = predicted_clock_interval_in_samples / one_ppqn_in_samples;
239 /* _bpm (really, _qpm) is absolute */
241 /* detect substantial changes in apparent tempo (defined as a
242 * change of more than 20% of the current tempo.
245 const double lpf_coeff = 0.063;
247 if (fabs (instantaneous_bpm - _bpm) > (0.20 * _bpm)) {
248 _bpm = instantaneous_bpm;
250 _bpm += lpf_coeff * (instantaneous_bpm - _bpm);
253 calculate_filter_coefficients (_bpm);
255 // need at least two clock events to compute speed
258 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("start mclock running with speed = %1\n", (t1 - t0) / one_ppqn_in_samples));
263 current.update (current.position + one_ppqn_in_samples, timestamp, speed);
265 if (TransportMasterManager::instance().current().get() == this) {
266 _session->maybe_update_tempo_from_midiclock_tempo (_bpm);
270 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("clock #%1 @ %2 should-be %3 transport %4 error %5 appspeed %6 "
271 "read-delta %7 should-be delta %8 t1-t0 %9 t0 %10 t1 %11 framerate %12 engine %13 running %14\n",
272 midi_clock_count, // #
273 elapsed_since_start, // @
274 current.position, // should-be
275 _session->transport_sample(), // transport
277 (t1 - t0) / one_ppqn_in_samples, // appspeed
278 timestamp - current.timestamp, // read delta
279 one_ppqn_in_samples, // should-be delta
283 ENGINE->sample_rate(), // framerate
284 ENGINE->sample_time(),
291 MIDIClock_TransportMaster::start (Parser& /*parser*/, samplepos_t timestamp)
293 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("MIDIClock_TransportMaster got start message at time %1 engine time %2 transport_sample %3\n", timestamp, ENGINE->sample_time(), _session->transport_sample()));
298 current.update (_session->transport_sample(), timestamp, 0);
303 MIDIClock_TransportMaster::reset (bool with_position)
305 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("MidiClock Master reset(): calculated filter for period size %2\n", ENGINE->samples_per_cycle()));
308 current.update (_session->transport_sample(), 0, 0);
318 MIDIClock_TransportMaster::contineu (Parser& /*parser*/, samplepos_t /*timestamp*/)
320 DEBUG_TRACE (DEBUG::MidiClock, "MIDIClock_TransportMaster got continue message\n");
326 MIDIClock_TransportMaster::stop (Parser& /*parser*/, samplepos_t timestamp)
328 DEBUG_TRACE (DEBUG::MidiClock, "MIDIClock_TransportMaster got stop message\n");
333 // we need to go back to the last MIDI beat (6 ppqn)
334 // and lets hope the tempo didnt change in the meantime :)
336 // begin at the should be position, because
337 // that is the position of the last MIDI Clock
338 // message and that is probably what the master
339 // expects where we are right now
341 // find out the last MIDI beat: go back #midi_clocks mod 6
342 // and lets hope the tempo didnt change in those last 6 beats :)
343 current.update (current.position - (midi_clock_count % 6) * one_ppqn_in_samples, 0, 0);
348 MIDIClock_TransportMaster::position (Parser& /*parser*/, MIDI::byte* message, size_t size, samplepos_t timestamp)
350 // we are not supposed to get position messages while we are running
351 // so lets be robust and ignore those
357 MIDI::byte lsb = message[1];
358 MIDI::byte msb = message[2];
359 assert((lsb <= 0x7f) && (msb <= 0x7f));
361 uint16_t position_in_sixteenth_notes = (uint16_t(msb) << 7) | uint16_t(lsb);
362 samplepos_t position_in_samples = calculate_song_position(position_in_sixteenth_notes);
364 DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Song Position: %1 samples: %2\n", position_in_sixteenth_notes, position_in_samples));
366 current.update (position_in_samples, timestamp, current.speed);
370 MIDIClock_TransportMaster::locked () const
376 MIDIClock_TransportMaster::ok() const
382 MIDIClock_TransportMaster::starting() const
388 MIDIClock_TransportMaster::update_interval() const
390 if (one_ppqn_in_samples) {
391 return resolution ();
394 return AudioEngine::instance()->sample_rate() / 120 / 4; /* pure guesswork */
398 MIDIClock_TransportMaster::resolution() const
401 return (samplecnt_t) one_ppqn_in_samples * ppqn;
405 MIDIClock_TransportMaster::position_string () const
407 return std::string();
411 MIDIClock_TransportMaster::delta_string() const
415 current.safe_read (last);
417 if (last.timestamp == 0 || starting()) {
418 snprintf(delta, sizeof(delta), "\u2012\u2012\u2012\u2012");
420 snprintf(delta, sizeof(delta), "\u0394<span foreground=\"green\" face=\"monospace\" >%s%s%" PRIi64 "</span>sm",
421 LEADINGZERO(abs(_current_delta)), PLUSMINUS(-_current_delta), abs(_current_delta));
423 return std::string(delta);
427 MIDIClock_TransportMaster::unregister_port ()
430 TransportMaster::unregister_port ();