From 976fc86811bbef6e8b79ed6157155593e5122740 Mon Sep 17 00:00:00 2001 From: Robin Gareus Date: Sun, 4 Aug 2013 16:13:43 +0200 Subject: fix no-roll LTC encoder, honor locates when transport is stopped --- libs/ardour/session_ltc.cc | 43 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 37 insertions(+), 6 deletions(-) (limited to 'libs/ardour/session_ltc.cc') diff --git a/libs/ardour/session_ltc.cc b/libs/ardour/session_ltc.cc index f293970dd4..d873bc07f9 100644 --- a/libs/ardour/session_ltc.cc +++ b/libs/ardour/session_ltc.cc @@ -82,6 +82,7 @@ Session::ltc_tx_initialize() * since the fps can change and A3's min fps: 24000/1001 */ ltc_enc_buf = (ltcsnd_sample_t*) calloc((nominal_frame_rate() / 23), sizeof(ltcsnd_sample_t)); ltc_speed = 0; + ltc_prev_cycle = -1; ltc_tx_reset(); ltc_tx_resync_latency(); Xrun.connect_same_thread (*this, boost::bind (&Session::ltc_tx_reset, this)); @@ -132,6 +133,7 @@ Session::ltc_tx_parse_offset() { offset_tc.drop = timecode_drop_frames(); timecode_to_sample(offset_tc, ltc_timecode_offset, false, false); ltc_timecode_negative_offset = !offset_tc.negative; + ltc_prev_cycle = -1; } void @@ -214,7 +216,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end if (cur_timecode != ltc_enc_tcformat) { DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX1: TC format mismatch - reinit sr: %1 fps: %2\n", nominal_frame_rate(), timecode_to_frames_per_second(cur_timecode))); if (ltc_encoder_reinit(ltc_encoder, nominal_frame_rate(), - timecode_to_frames_per_second(cur_timecode), + timecode_to_frames_per_second(cur_timecode), TV_STANDARD(cur_timecode), 0 )) { PBD::error << _("LTC encoder: invalid framerate - LTC encoding is disabled for the remainder of this session.") << endmsg; @@ -244,10 +246,25 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end * The _generated timecode_ is offset by the port-latency, * therefore the offset depends on the direction of transport. */ - framepos_t cycle_start_frame = (current_speed < 0) ? (start_frame - ltc_out_latency.max) : (start_frame + ltc_out_latency.max); + framepos_t cycle_start_frame; + + if (current_speed < 0) { + cycle_start_frame = (start_frame - ltc_out_latency.max); + } else if (current_speed > 0) { + cycle_start_frame = (start_frame + ltc_out_latency.max); + } else { + /* There is no need to compensate for latency when not rolling + * rather send the accurate NOW timecode + * (LTC encoder compenates latency by sending earlier timecode) + */ + cycle_start_frame = start_frame; + } /* LTC TV standard offset */ - cycle_start_frame -= ltc_frame_alignment(frames_per_timecode_frame(), TV_STANDARD(cur_timecode)); + if (current_speed != 0) { + /* ditto - send "NOW" if not rolling */ + cycle_start_frame -= ltc_frame_alignment(frames_per_timecode_frame(), TV_STANDARD(cur_timecode)); + } /* cycle-start may become negative due to latency compensation */ if (cycle_start_frame < 0) { cycle_start_frame = 0; } @@ -262,7 +279,13 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end ltc_tx_reset(); } - if (ltc_speed != new_ltc_speed) { + if (ltc_speed != new_ltc_speed + /* but only once if, current_speed changes to 0. In that case + * new_ltc_speed is > 0 because (end_frame - start_frame) == jack-period for no-roll + * but ltc_speed will still be 0 + */ + && (current_speed != 0 || ltc_speed != current_speed) + ) { /* check ./libs/ardour/interpolation.cc CubicInterpolation::interpolate * if target_speed != current_speed we should interpolate, too. * @@ -272,7 +295,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end * end_frame is calculated from 'frames_moved' which includes the interpolation. * so we're good. */ - DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX2: speed change old: %1 cur: %2 tgt: %3 ctd: %4\n", ltc_speed, current_speed, target_speed, fabs(current_speed) - target_speed)); + DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX2: speed change old: %1 cur: %2 tgt: %3 ctd: %4\n", ltc_speed, current_speed, target_speed, fabs(current_speed) - target_speed, new_ltc_speed)); speed_changed = true; ltc_encoder_set_filter(ltc_encoder, LTC_RISE_TIME(new_ltc_speed)); } @@ -292,6 +315,10 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end ltc_speed = new_ltc_speed; return; } + if (start_frame != ltc_prev_cycle) { + DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX2: no-roll seek from %1 to %2 (%3)\n", ltc_prev_cycle, start_frame, cycle_start_frame)); + ltc_tx_reset(); + } } if (fabs(new_ltc_speed) > 10.0) { @@ -375,6 +402,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end } } + ltc_prev_cycle = start_frame; ltc_speed = new_ltc_speed; DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX2: transport speed %1.\n", ltc_speed)); @@ -400,6 +428,9 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end /* difference between current frame and TC frame in samples */ frameoffset_t soff = cycle_start_frame - tc_sample_start; + if (current_speed == 0) { + soff = 0; + } DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX3: A3cycle: %1 = A3tc: %2 +off: %3\n", cycle_start_frame, tc_sample_start, soff)); @@ -501,7 +532,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end restarting = true; } - if (cyc_off > 0 && cyc_off <= nframes) { + if (cyc_off >= 0 && cyc_off <= nframes) { /* offset in this cycle */ txf= rint(cyc_off / fabs(ltc_speed)); memset(out, 0, cyc_off * sizeof(Sample)); -- cgit v1.2.3