diff options
| author | Robin Gareus <robin@gareus.org> | 2012-10-23 17:10:31 +0000 |
|---|---|---|
| committer | Robin Gareus <robin@gareus.org> | 2012-10-23 17:10:31 +0000 |
| commit | 4600530d50fb31c4ba9f2e76ce258519a336c82a (patch) | |
| tree | 20a15309c8247383c0f49e78bb17404b0980e763 /libs/ardour/mtc_slave.cc | |
| parent | 93b13251fa3b2f5db81d6ea1c50c58333dc376a6 (diff) | |
MTC slave - resolve drift issue
Close loop of quarter-frame DLL and
also re-enable the deadzone around speed 1.0.
DLL bandwidth have been slightly adjusted empirically.
git-svn-id: svn://localhost/ardour2/branches/3.0@13323 d708f5d6-7413-0410-9779-e7cbd77b26cf
Diffstat (limited to 'libs/ardour/mtc_slave.cc')
| -rw-r--r-- | libs/ardour/mtc_slave.cc | 30 |
1 files changed, 14 insertions, 16 deletions
diff --git a/libs/ardour/mtc_slave.cc b/libs/ardour/mtc_slave.cc index 305b12186f..c94c14b986 100644 --- a/libs/ardour/mtc_slave.cc +++ b/libs/ardour/mtc_slave.cc @@ -221,7 +221,7 @@ MTC_Slave::read_current (SafeTime *st) const void MTC_Slave::init_mtc_dll(framepos_t tme, double qtr) { - omega = 2.0 * M_PI * qtr / double(session.frame_rate()); + omega = 2.0 * M_PI * qtr / 2.0 / double(session.frame_rate()); b = 1.4142135623730950488 * omega; c = omega * omega; @@ -243,26 +243,25 @@ MTC_Slave::update_mtc_qtr (Parser& /*p*/, int which_qtr, framepos_t now) mtc_frame += qtr * transport_direction; DEBUG_TRACE (DEBUG::MTC, string_compose ("qtr frame %1 at %2 -> mtc_frame: %3\n", which_qtr, now, mtc_frame)); - framepos_t ts = 0; double mtc_speed = 0; if (first_mtc_timestamp != 0) { /* update MTC DLL and calculate speed */ - const double e = double(transport_direction) * (double(now) - double(current.timestamp) - qtr_d); + const double e = mtc_frame - (double(transport_direction) * (double(now) - double(current.timestamp) + t0)); t0 = t1; t1 += b * e + e2; e2 += c * e; mtc_speed = (t1 - t0) / qtr_d; - ts = now; DEBUG_TRACE (DEBUG::MTC, string_compose ("qtr frame DLL t0:%1 t1:%2 err:%3 spd:%4 ddt:%5\n", t0, t1, e, mtc_speed, e2 - qtr_d)); - } - current.guard1++; - current.position = mtc_frame; - current.timestamp = ts; - current.speed = mtc_speed; - current.guard2++; + current.guard1++; + current.position = mtc_frame; + current.timestamp = now; + current.speed = mtc_speed; + current.guard2++; + + } maybe_reset (); last_inbound_frame = now; @@ -530,7 +529,7 @@ MTC_Slave::init_engine_dll (framepos_t pos, framepos_t inc) * But this is only really a problem if the user performs manual * seeks while transport is running and slaved to MTC. */ - oe = 2.0 * M_PI * double(inc/6.0) / double(session.frame_rate()); + oe = 2.0 * M_PI * double(inc) / 2.0 / double(session.frame_rate()); be = 1.4142135623730950488 * oe; ce = oe * oe; @@ -581,8 +580,7 @@ MTC_Slave::speed_and_position (double& speed, framepos_t& pos) } - - DEBUG_TRACE (DEBUG::MTC, string_compose ("MTC::speed_and_position mtc-tme: %1 mtc-pos: %2\n", last.timestamp, last.position)); + DEBUG_TRACE (DEBUG::MTC, string_compose ("MTC::speed_and_position mtc-tme: %1 mtc-pos: %2 mtc-spd: %3\n", last.timestamp, last.position, last.speed)); DEBUG_TRACE (DEBUG::MTC, string_compose ("MTC::speed_and_position eng-tme: %1 eng-pos: %2\n", now, sess_pos)); double speed_flt = last.speed; ///< MTC speed from MTC-quarter-frame DLL @@ -630,9 +628,9 @@ MTC_Slave::speed_and_position (double& speed, framepos_t& pos) queue_reset (false); } -#if 0 - /* provide a 1% deadzone to lock the speed */ - if (fabs(speed - 1.0) <= 0.01) +#if 1 + /* provide a .1% deadzone to lock the speed */ + if (fabs(speed - 1.0) <= 0.001) speed = 1.0; #endif |