2 Copyright (C) 2002-4 Paul Davis
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2 of the License, or
7 (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software
16 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 #include <sys/types.h>
24 #include <pbd/error.h>
25 #include <pbd/failed_constructor.h>
26 #include <pbd/pthread_utils.h>
28 #include <midi++/port.h>
29 #include <midi++/jack.h>
30 #include <ardour/slave.h>
31 #include <ardour/session.h>
32 #include <ardour/audioengine.h>
33 #include <ardour/cycles.h>
34 #include <ardour/tempo.h>
39 using namespace ARDOUR;
44 MIDIClock_Slave::MIDIClock_Slave (Session& s, MIDI::Port& p, int ppqn)
47 , accumulator_index (0)
48 , average_midi_clock_frame_duration (0.0)
53 for(int i = 0; i < accumulator_size; i++)
57 MIDIClock_Slave::~MIDIClock_Slave()
62 MIDIClock_Slave::rebind (MIDI::Port& p)
64 for (vector<sigc::connection>::iterator i = connections.begin(); i != connections.end(); ++i) {
70 std::cerr << "MIDIClock_Slave: connecting to port " << port->name() << std::endl;
72 connections.push_back (port->input()->timing.connect (mem_fun (*this, &MIDIClock_Slave::update_midi_clock)));
73 connections.push_back (port->input()->start.connect (mem_fun (*this, &MIDIClock_Slave::start)));
74 connections.push_back (port->input()->stop.connect (mem_fun (*this, &MIDIClock_Slave::stop)));
78 MIDIClock_Slave::update_midi_clock (Parser& parser, nframes_t timestamp)
80 nframes_t now = timestamp;
85 const Tempo& current_tempo = session.tempo_map().tempo_at(now);
86 const Meter& current_meter = session.tempo_map().meter_at(now);
87 double frames_per_beat =
88 current_tempo.frames_per_beat(session.frame_rate(),
91 double quarter_notes_per_beat = 4.0 / current_tempo.note_type();
92 double frames_per_quarter_note = frames_per_beat / quarter_notes_per_beat;
94 one_ppqn_in_frames = frames_per_quarter_note / ppqn;
96 // for the first MIDI clock event we dont have any past
97 // data, so we assume a sane tempo
98 if(last.timestamp == 0) {
99 current_midi_clock_frame_duration = one_ppqn_in_frames;
101 current_midi_clock_frame_duration = now - last.timestamp;
105 // moving average over incoming intervals
106 accumulator[accumulator_index++] = (float) current_midi_clock_frame_duration;
107 if(accumulator_index == accumulator_size)
108 accumulator_index = 0;
110 average_midi_clock_frame_duration = 0.0;
111 for(int i = 0; i < accumulator_size; i++)
112 average_midi_clock_frame_duration += accumulator[i];
113 average_midi_clock_frame_duration /= accumulator_size;
117 JACK_MidiPort *jack_port = dynamic_cast<JACK_MidiPort *>(port);
118 pthread_t process_thread_id = 0;
120 process_thread_id = jack_port->get_process_thread();
124 << " got MIDI Clock message at time " << now
125 << " session time: " << session.engine().frame_time()
126 << " transport position: " << session.transport_frame()
127 << " real delta: " << current_midi_clock_frame_duration
128 << " reference: " << one_ppqn_in_frames
129 << " average: " << average_midi_clock_frame_duration
134 current.position += one_ppqn_in_frames;
135 current.timestamp = now;
138 last_inbound_frame = now;
142 MIDIClock_Slave::start (Parser& parser, nframes_t timestamp)
145 nframes_t now = timestamp;
147 //cerr << "MIDIClock_Slave got start message at time " << now << " session time: " << session.engine().frame_time() << endl;
150 cerr << "Did not start because not locked!" << endl;
154 current_midi_clock_frame_duration = 0;
156 session.request_transport_speed(one_ppqn_in_frames / average_midi_clock_frame_duration);
158 current.position = 0;
159 current.timestamp = now;
167 MIDIClock_Slave::stop (Parser& parser, nframes_t timestamp)
169 //std::cerr << "MIDIClock_Slave got stop message" << endl;
171 current_midi_clock_frame_duration = 0;
174 current.position = 0;
175 current.timestamp = 0;
183 MIDIClock_Slave::read_current (SafeTime *st) const
188 error << _("MIDI Clock Slave: atomic read of current time failed, sleeping!") << endmsg;
196 } while (st->guard1 != st->guard2);
200 MIDIClock_Slave::locked () const
206 MIDIClock_Slave::ok() const
212 MIDIClock_Slave::speed_and_position (float& speed, nframes_t& pos)
214 float previous_speed;
216 nframes_t now = session.engine().frame_time();
221 previous_speed = one_ppqn_in_frames / average_midi_clock_frame_duration;
227 read_current (&last);
229 /* no timecode for 1/4 second ? conclude that its stopped */
231 if (last_inbound_frame &&
232 now > last_inbound_frame &&
233 now - last_inbound_frame > session.frame_rate() / 4) {
234 //cerr << "No MIDI Clock frames received for some time, stopping!" << endl;
236 session.request_locate (pos, false);
237 session.request_transport_speed (0);
238 this->stop(*port->input(), now);
243 //cerr << " now: " << now << " last: " << last.timestamp;
245 speed = one_ppqn_in_frames / average_midi_clock_frame_duration;
246 //cerr << " final speed: " << speed;
248 if (now > last.timestamp) {
249 // we are in between MIDI clock messages
250 // so we interpolate position according to speed
251 nframes_t elapsed = now - last.timestamp;
252 nframes_t delta = elapsed * speed;
253 //cerr << " elapsed: " << elapsed << " elapsed (scaled) " << delta;
254 pos = last.position + delta;
256 // A new MIDI clock message has arrived this cycle
257 pos = (last.position + session.transport_frame()) / 2.0;
258 previous_speed = speed;
262 cerr << " transport position now: " << session.transport_frame();
263 cerr << " calculated position: " << pos;
267 // we want start on frame 0 on the first call after a MIDI start
277 MIDIClock_Slave::resolution() const
279 return (nframes_t) one_ppqn_in_frames * 24;
283 MIDIClock_Slave::reset ()
286 last_inbound_frame = 0;
288 current.position = 0;
289 current.timestamp = 0;
292 session.request_locate(0, false);