ardour/ardour
ardour/ardour
13
1
Fork 0
Code Pull Requests Releases Activity

fix MTC generator

Browse Source 
git-svn-id: svn://localhost/ardour2/branches/3.0@13805 d708f5d6-7413-0410-9779-e7cbd77b26cf
This commit is contained in:
Robin Gareus 2013-01-08 00:14:43 +00:00
parent 193a576e28
commit bc5b49ea3a
1 changed files with 57 additions and 21 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

78
libs/ardour/session_midi.cc
View File

@ -358,25 +358,53 @@ Session::send_full_time_code (framepos_t const t)
_send_timecode_update = false;
if (_engine.freewheeling() || !Config->get_send_mtc() || _slave) {
if (_engine.freewheeling() || !Config->get_send_mtc()) {
return 0;
}
if (_slave && !_slave->locked()) {
return 0;
}
// Get timecode time for the given time
sample_to_timecode (t, timecode, true /* use_offset */, false /* no subframes */);
// sample-align outbound to rounded (no subframes) timecode
timecode_to_sample(timecode, outbound_mtc_timecode_frame, true, false);
transmitting_timecode_time = timecode;
outbound_mtc_timecode_frame = t;
framecnt_t const quarter_frame_duration = ((framecnt_t) _frames_per_timecode_frame) >> 2;
if (ceil((t - outbound_mtc_timecode_frame) / quarter_frame_duration) > 0) {
Timecode::increment (transmitting_timecode_time, config.get_subframes_per_frame());
outbound_mtc_timecode_frame += _frames_per_timecode_frame;
}
DEBUG_TRACE (DEBUG::MTC, string_compose ("Full MTC TC %1\n", outbound_mtc_timecode_frame));
// I don't understand this bit yet.. [DR]
// I do [rg]:
// according to MTC spec 24, 30 drop and 30 non-drop TC, the frame-number represented by 8 quarter frames must be even.
if (((mtc_timecode_bits >> 5) != MIDI::MTC_25_FPS) && (transmitting_timecode_time.frames % 2)) {
// start MTC quarter frame transmission on an even frame
Timecode::increment (transmitting_timecode_time, config.get_subframes_per_frame());
outbound_mtc_timecode_frame += _frames_per_timecode_frame;
}
// Compensate for audio latency
#if 0 // compensate for audio latency -- disabled [rg]
/* this needs more thought and work.
* the proper solution will be to just offset MTC by the MIDI port's latency.
*
* using worst_playback_latency() is wrong when the generated MTC is used to sync
* clients which send audio to Ardour for recording.
* worst_capture_latency() vs. worst_playback_latency()
*
* NB. similarly to session_ltc, the offset should be subtracted from the timecode to send,
* instead of being added to timestamp when to send the timecode.
* Otherwise the timestamp may not fall into the jack-cycle of the current _transport frame.
* and no MTC QF will be sent.
*/
outbound_mtc_timecode_frame += worst_playback_latency();
#endif
next_quarter_frame_to_send = 0;
// Sync slave to the same Timecode time as we are on
@ -412,11 +440,13 @@ Session::send_full_time_code (framepos_t const t)
int
Session::send_midi_time_code_for_cycle (framepos_t start_frame, framepos_t end_frame, pframes_t nframes)
{
// XXX only if _slave == MTC_slave; we could generate MTC from jack or LTC
if (_engine.freewheeling() || _slave || !_send_qf_mtc || transmitting_timecode_time.negative || (next_quarter_frame_to_send < 0)) {
if (_engine.freewheeling() || !_send_qf_mtc || transmitting_timecode_time.negative || (next_quarter_frame_to_send < 0)) {
// cerr << "(MTC) Not sending MTC\n";
return 0;
}
if (_slave && !_slave->locked()) {
return 0;
}
/* MTC is max. 30 fps - assert() below will fail
* TODO actually limit it to 24,25,29df,30fps
@ -432,10 +462,14 @@ Session::send_midi_time_code_for_cycle (framepos_t start_frame, framepos_t end_f
/* Duration of one quarter frame */
framecnt_t const quarter_frame_duration = ((framecnt_t) _frames_per_timecode_frame) >> 2;
DEBUG_TRACE (DEBUG::MTC, string_compose ("TF %1 SF %2 NQ %3 FD %4\n", start_frame, outbound_mtc_timecode_frame,
next_quarter_frame_to_send, quarter_frame_duration));
DEBUG_TRACE (DEBUG::MTC, string_compose ("TF %1 SF %2 MT %3 QF %4 QD %5\n",
_transport_frame, start_frame, outbound_mtc_timecode_frame,
next_quarter_frame_to_send, quarter_frame_duration));
assert ((outbound_mtc_timecode_frame + (next_quarter_frame_to_send * quarter_frame_duration)) >= _transport_frame);
if ((outbound_mtc_timecode_frame + (next_quarter_frame_to_send * quarter_frame_duration)) < _transport_frame) {
send_full_time_code (_transport_frame);
return 0;
}
/* Send quarter frames for this cycle */
while (end_frame > (outbound_mtc_timecode_frame + (next_quarter_frame_to_send * quarter_frame_duration))) {
@ -475,23 +509,25 @@ Session::send_midi_time_code_for_cycle (framepos_t start_frame, framepos_t end_f
assert (msg_time >= start_frame);
assert (msg_time < end_frame);
/* convert from session frames back to JACK frames using the transport speed */
pframes_t const out_stamp = (msg_time - start_frame) / _transport_speed;
assert (out_stamp < nframes);
if (msg_time >= start_frame) {
/* convert from session frames back to JACK frames using the transport speed */
pframes_t const out_stamp = (msg_time - start_frame) / _transport_speed;
assert (out_stamp < nframes);
if (MIDI::Manager::instance()->mtc_output_port()->midimsg (mtc_msg, 2, out_stamp)) {
error << string_compose(_("Session: cannot send quarter-frame MTC message (%1)"), strerror (errno))
<< endmsg;
return -1;
}
if (MIDI::Manager::instance()->mtc_output_port()->midimsg (mtc_msg, 2, out_stamp)) {
error << string_compose(_("Session: cannot send quarter-frame MTC message (%1)"), strerror (errno))
<< endmsg;
return -1;
}
#ifndef NDEBUG
DEBUG_STR_DECL(foo)
DEBUG_STR_APPEND(foo,"sending ");
DEBUG_STR_APPEND(foo, transmitting_timecode_time);
DEBUG_TRACE (DEBUG::MTC, string_compose ("%1 qfm = %2, stamp = %3\n", DEBUG_STR(foo).str(), next_quarter_frame_to_send,
out_stamp));
DEBUG_STR_DECL(foo)
DEBUG_STR_APPEND(foo,"sending ");
DEBUG_STR_APPEND(foo, transmitting_timecode_time);
DEBUG_TRACE (DEBUG::MTC, string_compose ("%1 qfm = %2, stamp = %3\n", DEBUG_STR(foo).str(), next_quarter_frame_to_send,
out_stamp));
#endif
}
// Increment quarter frame counter
next_quarter_frame_to_send++;