13
0
livetrax/libs/ardour/mididm.cc

141 lines
4.0 KiB
C++

/*
* Copyright (C) 2013-2014 Robin Gareus <robin@gareus.org>
*
* 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
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "ardour/mididm.h"
#include "ardour/port_engine.h"
using namespace ARDOUR;
MIDIDM::MIDIDM (framecnt_t sample_rate)
: _sample_rate (sample_rate)
, _monotonic_cnt (sample_rate)
, _last_signal_tme (0)
, _cnt_total (0)
, _dly_total (0)
, _min_delay (INT32_MAX)
, _max_delay (0)
, _avg_delay (0)
, _var_m (0)
, _var_s (0)
{
}
int64_t
MIDIDM::parse_mclk (uint8_t* buf, pframes_t timestamp) const
{
/* calculate time difference */
#define MODCLK (16384) // 1<<(2*7)
const int64_t tc = (_monotonic_cnt + timestamp) & 0x3fff; // MODCLK - 1;
const int64_t ti = ((buf[2] & 0x7f) << 7) | (buf[1] & 0x7f);
const int64_t tdiff = (MODCLK + tc - ti) % MODCLK;
#ifdef DEBUG_MIDIDM
printf("MCLK DELAY: #%5"PRId64" dt:%6"PRId64" [spl] (%6"PRId64" - %8"PRId64") @(%8"PRId64" + %d)\n",
_cnt_total, tdiff, tc, ti, _monotonic_cnt, timestamp);
#endif
return tdiff;
}
int64_t
MIDIDM::parse_mtc (uint8_t* buf, pframes_t timestamp) const
{
#define MODTC (2097152) // 1<<(3*7)
const int64_t tc = (_monotonic_cnt + timestamp) & 0x001FFFFF;
const int64_t ti = (buf[5] & 0x7f)
| ((buf[6] & 0x7f) << 7)
| ((buf[7] & 0x7f) << 14)
| ((buf[8] & 0x7f) << 21);
const int64_t tdiff = (MODTC + tc - ti) % MODTC;
#ifdef DEBUG_MIDIDM
printf("MTC DELAY: #%5"PRId64" dt:%6"PRId64" [spl] (%6"PRId64" - %8"PRId64") @(%8"PRId64" + %d)\n",
_cnt_total, tdiff, tc, ti, _monotonic_cnt, timestamp);
#endif
return tdiff;
}
int MIDIDM::process (pframes_t nframes, PortEngine &pe, void *midi_in, void *midi_out)
{
/* send midi event */
pe.midi_clear(midi_out);
#ifndef USE_MTC // use 3-byte song position
uint8_t obuf[3];
obuf[0] = 0xf2;
obuf[1] = (_monotonic_cnt) & 0x7f;
obuf[2] = (_monotonic_cnt >> 7) & 0x7f;
pe.midi_event_put (midi_out, 0, obuf, 3);
#else // sysex MTC frame
uint8_t obuf[10];
obuf[0] = 0xf0;
obuf[1] = 0x7f;
obuf[2] = 0x7f;
obuf[3] = 0x01;
obuf[4] = 0x01;
obuf[9] = 0xf7;
obuf[5] = (_monotonic_cnt ) & 0x7f;
obuf[6] = (_monotonic_cnt >> 7) & 0x7f;
obuf[7] = (_monotonic_cnt >> 14) & 0x7f;
obuf[8] = (_monotonic_cnt >> 21) & 0x7f;
pe.midi_event_put (midi_out, 0, obuf, 10);
#endif
/* process incoming */
const pframes_t nevents = pe.get_midi_event_count (midi_in);
#ifdef DEBUG_MIDIDM
printf("MIDI SEND: @%8"PRId64", recv: %d systime:%"PRId64"\n", _monotonic_cnt, nevents, g_get_monotonic_time());
#endif
for (pframes_t n = 0; n < nevents; ++n) {
pframes_t timestamp;
size_t size;
uint8_t* buf;
int64_t tdiff;
pe.midi_event_get (timestamp, size, &buf, midi_in, n);
if (size == 3 && buf[0] == 0xf2 )
{
tdiff = parse_mclk(buf, timestamp);
} else if (size == 10 && buf[0] == 0xf0)
{
tdiff = parse_mtc(buf, timestamp);
}
else
{
continue;
}
_last_signal_tme = _monotonic_cnt;
/* running variance */
if (_cnt_total == 0) {
_var_m = tdiff;
} else {
const double var_m1 = _var_m;
_var_m = _var_m + ((double)tdiff - _var_m) / (double)(_cnt_total + 1);
_var_s = _var_s + ((double)tdiff - _var_m) * ((double)tdiff - var_m1);
}
/* average and mix/max */
++_cnt_total;
_dly_total += tdiff;
_avg_delay = _dly_total / _cnt_total;
if (tdiff < _min_delay) _min_delay = tdiff;
if (tdiff > _max_delay) _max_delay = tdiff;
}
_monotonic_cnt += nframes;
return 0;
}