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* removed unnecessary method calls (preparse/postparse) in JACK_MidiPort

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* Changed calculation of current speed and transport position to double to avoid accumulating rounding errors

git-svn-id: svn://localhost/ardour2/branches/3.0@4106 d708f5d6-7413-0410-9779-e7cbd77b26cf
This commit is contained in:
Hans Baier 2008-11-07 20:31:05 +00:00
parent 72f286e10e
commit 6abd152d17
3 changed files with 27 additions and 28 deletions
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7
libs/ardour/ardour/slave.h
View file

@ -231,6 +231,9 @@ class MIDIClock_Slave : public Slave, public sigc::trackable {
/// the time stamp and transport position of the last inbound MIDI clock message
SafeTime current;
/// since current.position is integral, we need to keep track of decimal places
/// to be precise
double current_position;
/// The duration of the current MIDI clock frame in frames
nframes_t current_midi_clock_frame_duration;
@ -239,11 +242,11 @@ class MIDIClock_Slave : public Slave, public sigc::trackable {
/// how many MIDI clock frames to average over
static const int32_t accumulator_size = 4;
float accumulator[accumulator_size];
double accumulator[accumulator_size];
int32_t accumulator_index;
/// the running average of current_midi_clock_frame_duration
float average_midi_clock_frame_duration;
double average_midi_clock_frame_duration;
void reset ();
void start (MIDI::Parser& parser, nframes_t timestamp);

44
libs/ardour/midi_clock_slave.cc
View file

@ -85,13 +85,13 @@ MIDIClock_Slave::update_midi_clock (Parser& parser, nframes_t timestamp)
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.frame_rate(),
current_tempo.frames_per_beat(session.nominal_frame_rate(),
current_meter);
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 / ppqn;
one_ppqn_in_frames = frames_per_quarter_note / double (ppqn);
// for the first MIDI clock event we dont have any past
// data, so we assume a sane tempo
@ -100,20 +100,18 @@ MIDIClock_Slave::update_midi_clock (Parser& parser, nframes_t timestamp)
} else {
current_midi_clock_frame_duration = now - last.timestamp;
}
// moving average over incoming intervals
accumulator[accumulator_index++] = (float) current_midi_clock_frame_duration;
accumulator[accumulator_index++] = current_midi_clock_frame_duration;
if(accumulator_index == accumulator_size)
accumulator_index = 0;
average_midi_clock_frame_duration = 0.0;
for(int i = 0; i < accumulator_size; i++)
average_midi_clock_frame_duration += accumulator[i];
average_midi_clock_frame_duration /= accumulator_size;
average_midi_clock_frame_duration /= double(accumulator_size);
#if 0
#if 1
JACK_MidiPort *jack_port = dynamic_cast<JACK_MidiPort *>(port);
pthread_t process_thread_id = 0;
if(jack_port) {
@ -132,6 +130,7 @@ MIDIClock_Slave::update_midi_clock (Parser& parser, nframes_t timestamp)
current.guard1++;
current.position += one_ppqn_in_frames;
current_position += one_ppqn_in_frames;
current.timestamp = now;
current.guard2++;
@ -153,9 +152,10 @@ MIDIClock_Slave::start (Parser& parser, nframes_t timestamp)
current_midi_clock_frame_duration = 0;
session.request_transport_speed(one_ppqn_in_frames / average_midi_clock_frame_duration);
session.request_transport_speed(one_ppqn_in_frames / double(average_midi_clock_frame_duration));
current.guard1++;
current.position = 0;
current_position = 0;
current.timestamp = now;
current.guard2++;
@ -172,6 +172,7 @@ MIDIClock_Slave::stop (Parser& parser, nframes_t timestamp)
current.guard1++;
current.position = 0;
current_position = 0;
current.timestamp = 0;
current.guard2++;
@ -211,23 +212,17 @@ MIDIClock_Slave::ok() const
bool
MIDIClock_Slave::speed_and_position (float& speed, nframes_t& pos)
{
float previous_speed;
nframes_t now = session.engine().frame_time();
if(!_started) {
if (!_started) {
speed = 0.0;
pos = 0;
previous_speed = one_ppqn_in_frames / average_midi_clock_frame_duration;
return true;
}
nframes_t now = session.engine().frame_time();
SafeTime last;
read_current (&last);
/* no timecode for 1/4 second ? conclude that its stopped */
if (last_inbound_frame &&
now > last_inbound_frame &&
now - last_inbound_frame > session.frame_rate() / 4) {
@ -242,20 +237,20 @@ MIDIClock_Slave::speed_and_position (float& speed, nframes_t& pos)
//cerr << " now: " << now << " last: " << last.timestamp;
speed = one_ppqn_in_frames / average_midi_clock_frame_duration;
// calculate speed
double speed_double = one_ppqn_in_frames / average_midi_clock_frame_duration;
speed = float(speed_double);
//cerr << " final speed: " << speed;
// calculate position
if (now > last.timestamp) {
// we are in between MIDI clock messages
// so we interpolate position according to speed
nframes_t elapsed = now - last.timestamp;
nframes_t delta = elapsed * speed;
//cerr << " elapsed: " << elapsed << " elapsed (scaled) " << delta;
pos = last.position + delta;
pos = nframes_t (current_position + double(elapsed) * speed_double);
} else {
// A new MIDI clock message has arrived this cycle
pos = (last.position + session.transport_frame()) / 2.0;
previous_speed = speed;
pos = current_position;
}
/*
@ -265,7 +260,7 @@ MIDIClock_Slave::speed_and_position (float& speed, nframes_t& pos)
*/
// we want start on frame 0 on the first call after a MIDI start
if(_starting) {
if (_starting) {
pos = 0;
_starting = false;
}
@ -286,6 +281,7 @@ MIDIClock_Slave::reset ()
last_inbound_frame = 0;
current.guard1++;
current.position = 0;
current_position = 0;
current.timestamp = 0;
current.guard2++;

4
libs/midi++2/jack_midiport.cc
View file

@ -76,13 +76,11 @@ JACK_MidiPort::cycle_start (nframes_t nframes)
jack_midi_event_get (&ev, jack_buffer, i);
if (input_parser) {
input_parser->raw_preparse (*input_parser, ev.buffer, ev.size);
for (size_t i = 0; i < ev.size; i++) {
// the midi events here are used for MIDI clock only
input_parser->set_midi_clock_timestamp(ev.time + jack_last_frame_time(_jack_client));
input_parser->scanner (ev.buffer[i]);
}
input_parser->raw_postparse (*input_parser, ev.buffer, ev.size);
}
}
}
@ -199,6 +197,8 @@ JACK_MidiPort::read(byte * buf, size_t bufsize)
jack_midi_event_t ev;
cerr << "JACK_MidiPort::read called" << endl;
int err = jack_midi_event_get (&ev,
jack_port_get_buffer(_jack_input_port, _nframes_this_cycle),
_last_read_index++);