X-Git-Url: https://main.carlh.net/gitweb/?a=blobdiff_plain;f=libs%2Fardour%2Fsession_ltc.cc;h=2cd21f9afd77b63f7ff902ae1b2a0fbf34afa7a1;hb=4bdbe77414b956e27f2c1631e67189c70409a3d1;hp=25ba783fc7a08f0c8b8e50fc52d5501bbfc44ecf;hpb=8872844a60311c060f6a3f352c5972e2676157cd;p=ardour.git diff --git a/libs/ardour/session_ltc.cc b/libs/ardour/session_ltc.cc index 25ba783fc7..2cd21f9afd 100644 --- a/libs/ardour/session_ltc.cc +++ b/libs/ardour/session_ltc.cc @@ -31,7 +31,6 @@ using namespace std; using namespace ARDOUR; -using namespace MIDI; using namespace PBD; using namespace Timecode; @@ -56,17 +55,22 @@ using namespace Timecode; * This filter is adaptive so that fast vari-speed signals * will not be affected by it. */ -#define LTC_RISE_TIME(speed) MIN (100, MAX(25, (4000000 / ((speed==0)?1:speed) / engine().frame_rate()))) +#define LTC_RISE_TIME(speed) MIN (100, MAX(40, (4000000 / ((speed==0)?1:speed) / engine().sample_rate()))) + +#define TV_STANDARD(tcf) \ + (timecode_to_frames_per_second(tcf)==25.0 ? LTC_TV_625_50 : \ + timecode_has_drop_frames(tcf)? LTC_TV_525_60 : LTC_TV_FILM_24) void Session::ltc_tx_initialize() { ltc_enc_tcformat = config.get_timecode_format(); + ltc_tx_parse_offset(); DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX init sr: %1 fps: %2\n", nominal_frame_rate(), timecode_to_frames_per_second(ltc_enc_tcformat))); ltc_encoder = ltc_encoder_create(nominal_frame_rate(), timecode_to_frames_per_second(ltc_enc_tcformat), - -2); + TV_STANDARD(ltc_enc_tcformat), 0); ltc_encoder_set_bufsize(ltc_encoder, nominal_frame_rate(), 23.0); ltc_encoder_set_filter(ltc_encoder, LTC_RISE_TIME(1.0)); @@ -77,6 +81,7 @@ 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)); @@ -88,7 +93,8 @@ void Session::ltc_tx_cleanup() { DEBUG_TRACE (DEBUG::LTC, "LTC TX cleanup\n"); - if (ltc_enc_buf) free(ltc_enc_buf); + free(ltc_enc_buf); + ltc_enc_buf = NULL; ltc_encoder_free(ltc_encoder); ltc_encoder = NULL; } @@ -118,6 +124,17 @@ Session::ltc_tx_reset() ltc_encoder_reset(ltc_encoder); } +void +Session::ltc_tx_parse_offset() { + Timecode::Time offset_tc; + Timecode::parse_timecode_format(config.get_timecode_generator_offset(), offset_tc); + offset_tc.rate = timecode_frames_per_second(); + 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 Session::ltc_tx_recalculate_position() { @@ -135,7 +152,7 @@ Session::ltc_tx_recalculate_position() Timecode::timecode_to_sample (a3tc, ltc_enc_pos, true, false, (double)frame_rate(), config.get_subframes_per_frame(), - config.get_timecode_generator_offset_negative(), config.get_timecode_generator_offset() + ltc_timecode_negative_offset, ltc_timecode_offset ); restarting = false; } @@ -197,13 +214,17 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end TimecodeFormat cur_timecode = config.get_timecode_format(); 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), -2)) { + if (ltc_encoder_reinit(ltc_encoder, nominal_frame_rate(), + 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; ltc_tx_cleanup(); return; } ltc_encoder_set_filter(ltc_encoder, LTC_RISE_TIME(ltc_speed)); ltc_enc_tcformat = cur_timecode; + ltc_tx_parse_offset(); ltc_tx_reset(); } @@ -223,8 +244,39 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end /* port latency compensation: * The _generated timecode_ is offset by the port-latency, * therefore the offset depends on the direction of transport. + * + * latency is compensated by adding it to the timecode to + * be generated. e.g. if the signal will reach the output in + * N samples time from now, generate the timecode for (now + N). + * + * sample-sync is achieved by further calculating the difference + * between the timecode and the session-transport and offsetting the + * buffer. + * + * The timecode is generated directly in the Session process callback + * using _transport_frame. It requires that the session has set the + * port's playback latency to worst_playback_latency() prior to + * calling ltc_tx_send_time_code_for_cycle(). */ - 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 + worst_playback_latency()); + } else if (current_speed > 0) { + cycle_start_frame = (start_frame + ltc_out_latency.max - worst_playback_latency()); + } 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 */ + 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; } @@ -239,7 +291,13 @@ 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. * @@ -249,7 +307,7 @@ 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)); } @@ -269,6 +327,10 @@ 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) { @@ -352,6 +414,7 @@ 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)); @@ -365,18 +428,21 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end timecode_drop_frames(), (double)frame_rate(), config.get_subframes_per_frame(), - config.get_timecode_generator_offset_negative(), config.get_timecode_generator_offset() + ltc_timecode_negative_offset, ltc_timecode_offset ); /* convert timecode back to sample-position */ Timecode::timecode_to_sample (tc_start, tc_sample_start, true, false, (double)frame_rate(), config.get_subframes_per_frame(), - config.get_timecode_generator_offset_negative(), config.get_timecode_generator_offset() + ltc_timecode_negative_offset, ltc_timecode_offset ); /* 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)); @@ -442,7 +508,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end DEBUG_TRACE (DEBUG::LTC, string_compose("LTC TX4: now: %1 trs: %2 toff %3\n", cycle_start_frame, tc_sample_start, soff)); - uint32_t cyc_off; + int32_t cyc_off; if (soff < 0 || soff >= fptcf) { /* session framerate change between (2) and now */ ltc_tx_reset(); @@ -478,7 +544,7 @@ 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 <= (int32_t) nframes) { /* offset in this cycle */ txf= rint(cyc_off / fabs(ltc_speed)); memset(out, 0, cyc_off * sizeof(Sample)); @@ -511,7 +577,7 @@ Session::ltc_tx_send_time_code_for_cycle (framepos_t start_frame, framepos_t end * To do better than this, resampling (or a rewrite of the * encoder) is required. */ - ltc_speed -= ((ltc_enc_pos + ltc_enc_cnt - poff) - cycle_start_frame) / engine().frame_rate(); + ltc_speed -= ((ltc_enc_pos + ltc_enc_cnt - poff) - cycle_start_frame) / engine().sample_rate(); }