/*
- Copyright (C) 2002-4 Paul Davis
+ Copyright (C) 2008 Paul Davis
+ Author: Hans Baier
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
*/
+#include <cmath>
#include <errno.h>
#include <poll.h>
#include <sys/types.h>
#include <unistd.h>
-#include <pbd/error.h>
-#include <pbd/failed_constructor.h>
-#include <pbd/pthread_utils.h>
+#include "pbd/error.h"
+#include "pbd/failed_constructor.h"
+#include "pbd/pthread_utils.h"
+#include "pbd/convert.h"
-#include <midi++/port.h>
-#include <ardour/slave.h>
-#include <ardour/session.h>
-#include <ardour/audioengine.h>
-#include <ardour/cycles.h>
-#include <ardour/tempo.h>
+#include "midi++/port.h"
+
+#include "ardour/debug.h"
+#include "ardour/midi_buffer.h"
+#include "ardour/midi_port.h"
+#include "ardour/slave.h"
+#include "ardour/tempo.h"
#include "i18n.h"
+using namespace std;
using namespace ARDOUR;
-using namespace sigc;
using namespace MIDI;
using namespace PBD;
-MIDIClock_Slave::MIDIClock_Slave (Session& s, MIDI::Port& p, int ppqn)
- : session (s)
- , ppqn (ppqn)
+MIDIClock_Slave::MIDIClock_Slave (Session& s, MidiPort& p, int ppqn)
+ : ppqn (ppqn)
+ , bandwidth (2.0 / 60.0) // 1 BpM = 1 / 60 Hz
{
+ session = (ISlaveSessionProxy *) new SlaveSessionProxy(s);
rebind (p);
reset ();
}
+MIDIClock_Slave::MIDIClock_Slave (ISlaveSessionProxy* session_proxy, int ppqn)
+ : session(session_proxy)
+ , ppqn (ppqn)
+ , bandwidth (2.0 / 60.0) // 1 BpM = 1 / 60 Hz
+{
+ reset ();
+}
+
MIDIClock_Slave::~MIDIClock_Slave()
{
+ delete session;
}
void
-MIDIClock_Slave::rebind (MIDI::Port& p)
+MIDIClock_Slave::rebind (MidiPort& port)
{
- for (vector<sigc::connection>::iterator i = connections.begin(); i != connections.end(); ++i) {
- (*i).disconnect ();
- }
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("MIDIClock_Slave: connecting to port %1\n", port.name()));
+
+ port_connections.drop_connections ();
+
+ port.self_parser().timing.connect_same_thread (port_connections, boost::bind (&MIDIClock_Slave::update_midi_clock, this, _1, _2));
+ port.self_parser().start.connect_same_thread (port_connections, boost::bind (&MIDIClock_Slave::start, this, _1, _2));
+ port.self_parser().contineu.connect_same_thread (port_connections, boost::bind (&MIDIClock_Slave::contineu, this, _1, _2));
+ port.self_parser().stop.connect_same_thread (port_connections, boost::bind (&MIDIClock_Slave::stop, this, _1, _2));
+ port.self_parser().position.connect_same_thread (port_connections, boost::bind (&MIDIClock_Slave::position, this, _1, _2, 3));
+
+}
+
+void
+MIDIClock_Slave::calculate_one_ppqn_in_frames_at(framepos_t time)
+{
+ const Tempo& current_tempo = session->tempo_map().tempo_at(time);
+ double frames_per_beat = current_tempo.frames_per_beat(session->frame_rate());
- port = &p;
+ double quarter_notes_per_beat = 4.0 / current_tempo.note_type();
+ double frames_per_quarter_note = frames_per_beat / quarter_notes_per_beat;
+
+ one_ppqn_in_frames = frames_per_quarter_note / double (ppqn);
+ // DEBUG_TRACE (DEBUG::MidiClock, string_compose ("at %1, one ppqn = %2\n", time, one_ppqn_in_frames));
+}
+
+ARDOUR::framepos_t
+MIDIClock_Slave::calculate_song_position(uint16_t song_position_in_sixteenth_notes)
+{
+ framepos_t song_position_frames = 0;
+ for (uint16_t i = 1; i <= song_position_in_sixteenth_notes; ++i) {
+ // one quarter note contains ppqn pulses, so a sixteenth note is ppqn / 4 pulses
+ calculate_one_ppqn_in_frames_at(song_position_frames);
+ song_position_frames += one_ppqn_in_frames * (framepos_t)(ppqn / 4);
+ }
- std::cerr << "MIDIClock_Slave: connecting to port " << port->name() << std::endl;
+ return song_position_frames;
+}
- connections.push_back (port->input()->timing.connect (mem_fun (*this, &MIDIClock_Slave::update_midi_clock)));
- connections.push_back (port->input()->start.connect (mem_fun (*this, &MIDIClock_Slave::start)));
- connections.push_back (port->input()->stop.connect (mem_fun (*this, &MIDIClock_Slave::stop)));
+void
+MIDIClock_Slave::calculate_filter_coefficients()
+{
+ // omega = 2 * PI * Bandwidth / MIDI clock frame frequency in Hz
+ omega = 2.0 * M_PI * bandwidth * one_ppqn_in_frames / session->frame_rate();
+ b = 1.4142135623730950488 * omega;
+ c = omega * omega;
}
void
-MIDIClock_Slave::update_midi_clock (Parser& parser)
+MIDIClock_Slave::update_midi_clock (Parser& /*parser*/, framepos_t timestamp)
{
- // ignore clock events if no start event received
- if(!_started)
+ // some pieces of hardware send MIDI Clock all the time
+ if ( (!_starting) && (!_started) ) {
return;
+ }
- nframes_t now = session.engine().frame_time();
+ pframes_t cycle_offset = timestamp - session->sample_time_at_cycle_start();
- SafeTime last;
- read_current (&last);
+ calculate_one_ppqn_in_frames_at(should_be_position);
- const Tempo& current_tempo = session.tempo_map().tempo_at(now);
- const Meter& current_meter = session.tempo_map().meter_at(now);
- double frames_per_beat =
- current_tempo.frames_per_beat(session.nominal_frame_rate(),
- current_meter);
+ framepos_t elapsed_since_start = timestamp - first_timestamp;
+ double error = 0;
- double quarter_notes_per_beat = 4.0 / current_tempo.note_type();
- double frames_per_quarter_note = frames_per_beat / quarter_notes_per_beat;
+ if (_starting || last_timestamp == 0) {
+ midi_clock_count = 0;
- one_ppqn_in_frames = frames_per_quarter_note / ppqn;
+ first_timestamp = timestamp;
+ elapsed_since_start = should_be_position;
- /*
- Also compensate for audio latency.
- */
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("first clock message after start received @ %1\n", timestamp));
- midi_clock_frame += (long) (one_ppqn_in_frames)
- + session.worst_output_latency();
+ // calculate filter coefficients
+ calculate_filter_coefficients();
- /*
- std::cerr << "got MIDI Clock message at time " << now
- << " result: " << midi_clock_frame
- << " open_ppqn_in_frames: " << one_ppqn_in_frames << std::endl;
- */
-
- if (first_midi_clock_frame == 0) {
- first_midi_clock_frame = midi_clock_frame;
- first_midi_clock_time = now;
+ // initialize DLL
+ e2 = double(one_ppqn_in_frames) / double(session->frame_rate());
+ t0 = double(elapsed_since_start) / double(session->frame_rate());
+ t1 = t0 + e2;
+
+ // let ardour go after first MIDI Clock Event
+ _starting = false;
+ } else {
+ midi_clock_count++;
+ should_be_position += one_ppqn_in_frames;
+ calculate_filter_coefficients();
+
+ // calculate loop error
+ // we use session->transport_frame() instead of t1 here
+ // because t1 is used to calculate the transport speed,
+ // so the loop will compensate for accumulating rounding errors
+ error = (double(should_be_position) - (double(session->transport_frame()) + double(cycle_offset)));
+ e = error / double(session->frame_rate());
+ current_delta = error;
+
+ // update DLL
+ t0 = t1;
+ t1 += b * e + e2;
+ e2 += c * e;
}
- current.guard1++;
- current.position = midi_clock_frame;
- current.timestamp = now;
- current.guard2++;
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("clock #%1 @ %2 should-be %3 transport %4 error %5 appspeed %6 "
+ "read-delta %7 should-be delta %8 t1-t0 %9 t0 %10 t1 %11 framerate %12 engine %13\n",
+ midi_clock_count, // #
+ elapsed_since_start, // @
+ should_be_position, // should-be
+ session->transport_frame(), // transport
+ error, // error
+ ((t1 - t0) * session->frame_rate()) / one_ppqn_in_frames, // appspeed
+ timestamp - last_timestamp, // read delta
+ one_ppqn_in_frames, // should-be delta
+ (t1 - t0) * session->frame_rate(), // t1-t0
+ t0 * session->frame_rate(), // t0
+ t1 * session->frame_rate(), // t1
+ session->frame_rate(), // framerate
+ session->frame_time()
+
+ ));
+
+ last_timestamp = timestamp;
+}
+
+void
+MIDIClock_Slave::start (Parser& /*parser*/, framepos_t timestamp)
+{
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("MIDIClock_Slave got start message at time %1 engine time %2 transport_frame %3\n", timestamp, session->frame_time(), session->transport_frame()));
+
+ if (!_started) {
+ reset();
+
+ _started = true;
+ _starting = true;
- last_inbound_frame = now;
+ should_be_position = session->transport_frame();
+ }
}
void
-MIDIClock_Slave::start (Parser& parser)
+MIDIClock_Slave::reset ()
{
- std::cerr << "MIDIClock_Slave got start message" << endl;
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("MidiClock_Slave reset(): calculated filter bandwidth is %1 for period size %2\n", bandwidth, session->frames_per_cycle()));
- midi_clock_speed = 1.0f;
- _started = true;
+ should_be_position = session->transport_frame();
+ last_timestamp = 0;
+
+ _starting = true;
+ _started = true;
+
+ // session->request_locate(0, false);
+ current_delta = 0;
}
void
-MIDIClock_Slave::stop (Parser& parser)
+MIDIClock_Slave::contineu (Parser& /*parser*/, framepos_t /*timestamp*/)
{
- std::cerr << "MIDIClock_Slave got stop message" << endl;
+ DEBUG_TRACE (DEBUG::MidiClock, "MIDIClock_Slave got continue message\n");
- midi_clock_speed = 0.0f;
- _started = false;
+ if (!_started) {
+ _starting = true;
+ _started = true;
+ }
}
+
void
-MIDIClock_Slave::read_current (SafeTime *st) const
+MIDIClock_Slave::stop (Parser& /*parser*/, framepos_t /*timestamp*/)
{
- int tries = 0;
- do {
- if (tries == 10) {
- error << _("MIDI Clock Slave: atomic read of current time failed, sleeping!") << endmsg;
- usleep (20);
- tries = 0;
- }
-
- *st = current;
- tries++;
-
- } while (st->guard1 != st->guard2);
+ DEBUG_TRACE (DEBUG::MidiClock, "MIDIClock_Slave got stop message\n");
+
+ if (_started || _starting) {
+ _starting = false;
+ _started = false;
+ // locate to last MIDI clock position
+ session->request_transport_speed(0.0);
+
+ // we need to go back to the last MIDI beat (6 ppqn)
+ // and lets hope the tempo didnt change in the meantime :)
+
+ // begin at the should be position, because
+ // that is the position of the last MIDI Clock
+ // message and that is probably what the master
+ // expects where we are right now
+ framepos_t stop_position = should_be_position;
+
+ // find out the last MIDI beat: go back #midi_clocks mod 6
+ // and lets hope the tempo didnt change in those last 6 beats :)
+ stop_position -= (midi_clock_count % 6) * one_ppqn_in_frames;
+
+ session->request_locate(stop_position, false);
+ should_be_position = stop_position;
+ last_timestamp = 0;
+ }
+}
+
+void
+MIDIClock_Slave::position (Parser& /*parser*/, byte* message, size_t size)
+{
+ // we are note supposed to get position messages while we are running
+ // so lets be robust and ignore those
+ if (_started || _starting) {
+ return;
+ }
+
+ assert(size == 3);
+ byte lsb = message[1];
+ byte msb = message[2];
+ assert((lsb <= 0x7f) && (msb <= 0x7f));
+
+ uint16_t position_in_sixteenth_notes = (uint16_t(msb) << 7) | uint16_t(lsb);
+ framepos_t position_in_frames = calculate_song_position(position_in_sixteenth_notes);
+
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("Song Position: %1 frames: %2\n", position_in_sixteenth_notes, position_in_frames));
+
+ session->request_locate(position_in_frames, false);
+ should_be_position = position_in_frames;
+ last_timestamp = 0;
+
}
bool
}
bool
-MIDIClock_Slave::speed_and_position (float& speed, nframes_t& pos)
+MIDIClock_Slave::starting() const
{
- //std::cerr << "MIDIClock_Slave speed and position() called" << endl;
-
- nframes_t now = session.engine().frame_time();
- nframes_t frame_rate = session.frame_rate();
- nframes_t elapsed;
- float speed_now;
-
- SafeTime last;
- read_current (&last);
-
- if (first_midi_clock_time == 0) {
- speed = 0;
- pos = last.position;
- return true;
- }
+ return false;
+}
+bool
+MIDIClock_Slave::stop_if_no_more_clock_events(framepos_t& pos, framepos_t now)
+{
/* no timecode for 1/4 second ? conclude that its stopped */
-
- if (last_inbound_frame && now > last_inbound_frame && now - last_inbound_frame > frame_rate / 4) {
- midi_clock_speed = 0;
- pos = last.position;
- session.request_locate (pos, false);
- session.request_transport_speed (0);
- this->stop(*port->input());
- reset();
+ if (last_timestamp &&
+ now > last_timestamp &&
+ now - last_timestamp > session->frame_rate() / 4) {
+ DEBUG_TRACE (DEBUG::MidiClock, "No MIDI Clock frames received for some time, stopping!\n");
+ pos = should_be_position;
+ session->request_transport_speed (0);
+ session->request_locate (should_be_position, false);
+ return true;
+ } else {
return false;
}
+}
- speed_now = (float) ((last.position - first_midi_clock_frame) / (double) (now - first_midi_clock_time));
-
- cerr << "speed_and_position: speed_now: " << speed_now ;
-
- accumulator[accumulator_index++] = speed_now;
-
- if (accumulator_index >= accumulator_size) {
- have_first_accumulated_speed = true;
- accumulator_index = 0;
+bool
+MIDIClock_Slave::speed_and_position (double& speed, framepos_t& pos)
+{
+ if (!_started || _starting) {
+ speed = 0.0;
+ pos = should_be_position;
+ return true;
}
- if (have_first_accumulated_speed) {
- float total = 0;
-
- for (int32_t i = 0; i < accumulator_size; ++i) {
- total += accumulator[i];
- }
-
- midi_clock_speed = total / accumulator_size;
-
- } else {
-
- midi_clock_speed = speed_now;
+ framepos_t engine_now = session->frame_time();
+ if (stop_if_no_more_clock_events(pos, engine_now)) {
+ return false;
}
- if (midi_clock_speed == 0.0f) {
+ // calculate speed
+ speed = ((t1 - t0) * session->frame_rate()) / one_ppqn_in_frames;
- elapsed = 0;
+ // provide a 0.1% deadzone to lock the speed
+ if (fabs(speed - 1.0) <= 0.001)
+ speed = 1.0;
+ // calculate position
+ if (engine_now > last_timestamp) {
+ // we are in between MIDI clock messages
+ // so we interpolate position according to speed
+ framecnt_t elapsed = engine_now - last_timestamp;
+ pos = (framepos_t) (should_be_position + double(elapsed) * speed);
} else {
-
- /* scale elapsed time by the current MIDI Clock speed */
-
- if (last.timestamp && (now > last.timestamp)) {
- elapsed = (nframes_t) floor (midi_clock_speed * (now - last.timestamp));
- } else {
- elapsed = 0; /* XXX is this right? */
- }
+ // A new MIDI clock message has arrived this cycle
+ pos = should_be_position;
}
- /* now add the most recent timecode value plus the estimated elapsed interval */
-
- pos = elapsed + last.position;
+ DEBUG_TRACE (DEBUG::MidiClock, string_compose ("speed_and_position: speed %1 should-be %2 transport %3 \n", speed, pos, session->transport_frame()));
- speed = midi_clock_speed;
-
- cerr << " final speed: " << speed << " position: " << pos << endl;
return true;
}
-ARDOUR::nframes_t
+ARDOUR::framecnt_t
MIDIClock_Slave::resolution() const
{
- return (nframes_t) one_ppqn_in_frames;
+ // one beat
+ return (framecnt_t) one_ppqn_in_frames * ppqn;
}
-void
-MIDIClock_Slave::reset ()
+std::string
+MIDIClock_Slave::approximate_current_delta() const
{
- /* XXX massive thread safety issue here. MTC could
- be being updated as we call this. but this
- supposed to be a realtime-safe call.
- */
-
- last_inbound_frame = 0;
- current.guard1++;
- current.position = 0;
- current.timestamp = 0;
- current.guard2++;
- first_midi_clock_frame = 0;
- first_midi_clock_time = 0;
-
- accumulator_index = 0;
- have_first_accumulated_speed = false;
- midi_clock_speed = 0;
+ char delta[80];
+ if (last_timestamp == 0 || _starting) {
+ snprintf(delta, sizeof(delta), "\u2012\u2012\u2012\u2012");
+ } else {
+ snprintf(delta, sizeof(delta), "\u0394<span foreground=\"green\" face=\"monospace\" >%s%s%" PRIi64 "</span>sm",
+ LEADINGZERO(abs(current_delta)), PLUSMINUS(-current_delta), abs(current_delta));
+ }
+ return std::string(delta);
}
+