LTC slave reworked
* detect LTC framerate * detect LTC discontinuities * use a DLL for flywheel sync (engine rate) * don't use seekahead - internal resync git-svn-id: svn://localhost/ardour2/branches/3.0@13291 d708f5d6-7413-0410-9779-e7cbd77b26cf
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@ -261,10 +261,10 @@ class MTC_Slave : public TimecodeSlave {
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bool requires_seekahead () const { return true; }
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framecnt_t seekahead_distance() const;
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bool give_slave_full_control_over_transport_speed() const;
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std::string approximate_current_delta() const;
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Timecode::TimecodeFormat apparent_timecode_format() const;
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std::string approximate_current_position() const;
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std::string approximate_current_delta() const;
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private:
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Session& session;
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@ -337,18 +337,22 @@ public:
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bool ok() const;
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framecnt_t resolution () const;
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bool requires_seekahead () const { return true; }
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bool requires_seekahead () const { return false; }
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framecnt_t seekahead_distance() const;
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bool give_slave_full_control_over_transport_speed() const;
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Timecode::TimecodeFormat apparent_timecode_format() const;
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std::string approximate_current_position() const;
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std::string approximate_current_delta() const;
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private:
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int parse_ltc(const jack_nframes_t, const jack_default_audio_sample_t * const, const framecnt_t);
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bool process_ltc(framepos_t, framecnt_t);
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void init_ltc_dll(framepos_t, double);
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void detect_ltc_fps(int, bool);
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bool process_ltc(framepos_t const, framepos_t const, framecnt_t);
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void init_ltc_dll(framepos_t const, double const);
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void init_engine_dll (framepos_t, framepos_t);
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bool detect_ltc_fps(int, bool);
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bool detect_ltc_discontinuity(LTCFrameExt *);
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void reset();
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Session& session;
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bool did_reset_tc_format;
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@ -357,11 +361,14 @@ public:
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LTCDecoder *decoder;
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Timecode::Time timecode;
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double frames_per_ltc_frame;
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bool ltc_discontinuity;
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framecnt_t monotonic_cnt;
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framecnt_t last_timestamp;
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framecnt_t last_ltc_frame;
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framepos_t ltc_transport_pos;
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double ltc_speed;
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frameoffset_t current_delta;
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int ltc_detect_fps_cnt;
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int ltc_detect_fps_max;
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@ -369,11 +376,26 @@ public:
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Timecode::TimecodeFormat a3e_timecode;
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bool printed_timecode_warning;
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/* DLL - chase MTC */
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LTCFrame prev_ltc_frame;
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uint64_t frames_in_sequence;
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int delayedlocked;
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/* DLL - chase LTC */
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double t0; ///< time at the beginning of the MTC quater frame
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double t1; ///< calculated end of the MTC quater frame
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double e2; ///< second order loop error
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double b, c, omega; ///< DLL filter coefficients
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/* DLL - sync engine */
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int transport_direction;
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int engine_dll_initstate;
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double te0; ///< time at the beginning of the engine process
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double te1; ///< calculated sync time
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double ee2; ///< second order loop error
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double be, ce, oe; ///< DLL filter coefficients
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};
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#endif
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@ -39,25 +39,30 @@ using namespace MIDI;
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using namespace PBD;
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using namespace Timecode;
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#define FLYWHEEL_TIMEOUT ( 3 * session.frame_rate() )
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LTC_Slave::LTC_Slave (Session& s)
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: session (s)
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{
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frames_per_ltc_frame = session.frames_per_timecode_frame();
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frames_per_ltc_frame = session.frames_per_timecode_frame(); // XXX at most 30fps ?
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timecode.rate = session.timecode_frames_per_second();
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timecode.drop = session.timecode_drop_frames();
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printf("LTC initial rate: %f %f\n", timecode.rate, frames_per_ltc_frame);
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ltc_transport_pos = 0;
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ltc_speed = 1.0;
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last_timestamp = 0;
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ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
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did_reset_tc_format = false;
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delayedlocked = 10;
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engine_dll_initstate = 0;
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monotonic_cnt = 0;
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memset(&prev_ltc_frame, 0, sizeof(LTCFrame));
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ltc_timecode = timecode_60; // track changes of LTC timecode
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a3e_timecode = timecode_60; // track canges of Ardour's timecode
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printed_timecode_warning = false;
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decoder = ltc_decoder_create((int) frames_per_ltc_frame, 128 /*queue size*/);
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reset();
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//session.engine().Xrun.connect_same_thread (*this, boost::bind (<C_Slave::reset, this));
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}
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LTC_Slave::~LTC_Slave()
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@ -85,13 +90,13 @@ LTC_Slave::resolution () const
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ARDOUR::framecnt_t
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LTC_Slave::seekahead_distance () const
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{
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return (framecnt_t) (frames_per_ltc_frame * 2);
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return 0;
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}
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bool
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LTC_Slave::locked () const
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{
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return true; // TODO check if >2 sequential LTC frames have been received
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return (delayedlocked < 5);
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}
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bool
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@ -100,6 +105,19 @@ LTC_Slave::ok() const
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return true;
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}
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void
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LTC_Slave::reset()
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{
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DEBUG_TRACE (DEBUG::LTC, "LTC reset()\n");
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frames_in_sequence = 0;
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ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
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last_timestamp = 0;
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current_delta = 0;
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transport_direction = 0;
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ltc_speed = 0;
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ltc_decoder_queue_flush(decoder);
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}
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int
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LTC_Slave::parse_ltc(const jack_nframes_t nframes, const jack_default_audio_sample_t * const in, const framecnt_t posinfo)
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{
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@ -115,7 +133,7 @@ LTC_Slave::parse_ltc(const jack_nframes_t nframes, const jack_default_audio_samp
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return 0;
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}
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void
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bool
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LTC_Slave::detect_ltc_fps(int frameno, bool df)
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{
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double detected_fps = 0;
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@ -151,7 +169,7 @@ LTC_Slave::detect_ltc_fps(int frameno, bool df)
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frames_per_ltc_frame = double(session.frame_rate()) / timecode.rate;
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC reset to FPS: %1%2 ; audio-frames per LTC: %3\n",
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detected_fps, df?"df":"ndf", frames_per_ltc_frame));
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last_timestamp = 0; // re-init
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return true; // reset()
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}
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/* poll and check session TC */
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@ -187,23 +205,57 @@ LTC_Slave::detect_ltc_fps(int frameno, bool df)
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ltc_timecode = tc_format;
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a3e_timecode = cur_timecode;
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}
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return false;
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}
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bool
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LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
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LTC_Slave::detect_ltc_discontinuity(LTCFrameExt *frame) {
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bool discontinuity_detected = false;
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/* detect discontinuities */
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if (frame->reverse) {
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ltc_frame_decrement(&prev_ltc_frame, ceil(timecode.rate), 0);
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} else {
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ltc_frame_increment(&prev_ltc_frame, ceil(timecode.rate), 0);
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}
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if (memcmp(&prev_ltc_frame, &frame->ltc, sizeof(LTCFrame))) {
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discontinuity_detected = true;
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}
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memcpy(&prev_ltc_frame, &frame->ltc, sizeof(LTCFrame));
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/* notfify about discontinuities */
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if (frames_in_sequence > 0 && discontinuity_detected) {
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fprintf(stdout, "# LTC DISCONTINUITY\n");
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frames_in_sequence=0;
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return true;
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}
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frames_in_sequence++;
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return false;
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}
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bool
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LTC_Slave::process_ltc(framepos_t const now, framepos_t const sess_pos, framecnt_t const nframes)
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{
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bool have_frame = false;
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framepos_t sess_pos = session.transport_frame(); // corresponds to now
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//sess_pos -= session.engine().frames_since_cycle_start();
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC Process eng-tme: %1 eng-pos: %2\n", now, sess_pos));
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LTCFrameExt frame;
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while (ltc_decoder_read(decoder,&frame)) {
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bool reinitialize_ltc_dll = false;
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SMPTETimecode stime;
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ltc_frame_to_time(&stime, &frame.ltc, 0);
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timecode.negative = false;
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timecode.subframes = 0;
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/* set timecode.rate and timecode.drop: */
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if (detect_ltc_fps(stime.frame, (frame.ltc.dfbit)? true : false)) {
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reset();
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break;
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}
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if (detect_ltc_discontinuity(&frame)) {
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ltc_discontinuity = true;
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}
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#if 0 // Devel/Debug
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fprintf(stdout, "LTC %02d:%02d:%02d%c%02d | %8lld %8lld%s\n",
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@ -216,12 +268,16 @@ LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
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frame.off_end,
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frame.reverse ? " R" : " "
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);
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#endif
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timecode.negative = false;
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timecode.subframes = 0;
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/* set timecode.rate and timecode.drop: */
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detect_ltc_fps(stime.frame, (frame.ltc.dfbit)? true : false);
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if (frames_in_sequence < 1) {
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fprintf(stdout, " ####### FIRST LTC FRAME in SEQ #######\n");
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continue;
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}
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if (ltc_discontinuity) {
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fprintf(stdout, " ####### LTC DISCONTINUITY #######\n");
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}
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#endif
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/* when a full LTC frame is decoded, the timecode the LTC frame
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* is referring has just passed.
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@ -244,45 +300,95 @@ LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
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timecode.seconds = stime.secs;
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timecode.frames = stime.frame;
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framepos_t ltc_frame;
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/* map LTC timecode to session TC setting */
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framepos_t ltc_frame; ///< audio-frame corresponding to LTC frame
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Timecode::timecode_to_sample (timecode, ltc_frame, true, false,
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double(session.frame_rate()),
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session.config.get_subframes_per_frame(),
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session.config.get_timecode_offset_negative(), session.config.get_timecode_offset()
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);
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double poff = (frame.off_end - now);
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/* (frame.off_end + 1) = start of next LTC frame */
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double poff = (frame.off_end + 1 - now);
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ltc_transport_pos = ltc_frame - poff;
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frames_per_ltc_frame = (double(session.frame_rate()) / timecode.rate);
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//frames_per_ltc_frame = frame.off_end - frame.off_start; // the first one is off.
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC frame: %1 poff: %2 pos :%3\n", ltc_frame, poff, ltc_transport_pos));
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#if 0 // vari-speed LTC, no DLL
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frames_per_ltc_frame = 1 + frame.off_end - frame.off_start;
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#else
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frames_per_ltc_frame = (double(session.frame_rate()) / timecode.rate);
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#endif
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC frame: %1 poff: %2 pos: %3\n", ltc_frame, poff, ltc_transport_pos));
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if (ltc_discontinuity) {
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ltc_discontinuity=false;
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if (ltc_speed==0
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|| !locked()
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|| (ltc_transport_pos - sess_pos) > FLYWHEEL_TIMEOUT)
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{
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engine_dll_initstate = 0;
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reset();
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}
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reinitialize_ltc_dll = true;
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}
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if (last_timestamp == 0
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|| ((now - last_timestamp) > FLYWHEEL_TIMEOUT)
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|| (abs(current_delta) > FLYWHEEL_TIMEOUT) // TODO LTC-delta not engine delta
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|| (frame.reverse && transport_direction != -1)
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|| (!frame.reverse && transport_direction != 1)
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) {
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reinitialize_ltc_dll = true;
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engine_dll_initstate = 0;
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reset();
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}
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if (reinitialize_ltc_dll) {
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init_ltc_dll(ltc_transport_pos, frames_per_ltc_frame);
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if (ltc_speed==0 || !locked()) {
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if (frame.reverse) {
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transport_direction = -1;
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ltc_transport_pos -= nframes * rint((2 * frames_per_ltc_frame + poff)/nframes);
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} else {
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transport_direction = 1;
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ltc_transport_pos += nframes * rint((2 * frames_per_ltc_frame + poff)/nframes);
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}
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}
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if (last_timestamp == 0 || ((now - last_timestamp) > 4 * frames_per_ltc_frame) ) {
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init_ltc_dll(ltc_frame, frames_per_ltc_frame);
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ltc_speed = 1.0; // XXX
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} else {
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double e = (double(ltc_frame) - poff - double(sess_pos));
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// update DLL
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double e = (double(ltc_frame) - poff - double(sess_pos));
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t0 = t1;
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t1 += b * e + e2;
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e2 += c * e;
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ltc_speed = (t1 - t0) / frames_per_ltc_frame;
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current_delta = (ltc_transport_pos - sess_pos);
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC DLL t0:%1 t1:%2 err:%3 spd:%4 ddt:%5\n", t0, t1, e, ltc_speed, e2 - frames_per_ltc_frame));
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}
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/* the are equivalent
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* TODO: choose the value with larger diff ->
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* minimize roundig errors when extrapolating
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*/
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#if 1
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last_timestamp = now;
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last_ltc_frame = ltc_transport_pos;
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#else
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last_timestamp = frame.off_end + 1;
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last_ltc_frame = ltc_frame;
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#endif
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have_frame = true;
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}
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} /* end foreach decoded LTC frame */
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return have_frame;
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}
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void
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LTC_Slave::init_ltc_dll(framepos_t tme, double dt)
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LTC_Slave::init_ltc_dll(framepos_t const tme, double const dt)
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{
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omega = 2.0 * M_PI * dt / double(session.frame_rate());
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b = 1.4142135623730950488 * omega;
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@ -294,6 +400,26 @@ LTC_Slave::init_ltc_dll(framepos_t tme, double dt)
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DEBUG_TRACE (DEBUG::LTC, string_compose ("[re-]init LTC DLL %1 %2 %3\n", t0, t1, e2));
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}
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void
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LTC_Slave::init_engine_dll (framepos_t pos, framepos_t inc)
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{
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/* the bandwidth of the DLL is a trade-off,
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* because the max-speed of the transport in ardour is
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* limited to +-8.0, a larger bandwidth would cause oscillations
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*
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* But this is only really a problem if the user performs manual
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* seeks while transport is running and slaved to LTC.
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*/
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oe = 2.0 * M_PI * double(inc/2.0) / double(session.frame_rate());
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be = 1.4142135623730950488 * oe;
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ce = oe * oe;
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ee2 = double(transport_direction * inc);
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te0 = double(pos);
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te1 = te0 + ee2;
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DEBUG_TRACE (DEBUG::LTC, string_compose ("[re-]init Engine DLL %1 %2 %3\n", te0, te1, ee2));
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}
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/* main entry point from session_process.cc
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* called from jack_process callback context
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* so it is OK to use jack_port_get_buffer() etc
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@ -301,39 +427,87 @@ LTC_Slave::init_ltc_dll(framepos_t tme, double dt)
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bool
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LTC_Slave::speed_and_position (double& speed, framepos_t& pos)
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{
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framepos_t now = session.engine().frame_time_at_cycle_start();
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//framepos_t now = session.engine().frame_time_at_cycle_start();
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//framepos_t now = session.engine().processed_frames();
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framepos_t now = monotonic_cnt;
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framepos_t sess_pos = session.transport_frame(); // corresponds to now
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framecnt_t nframes = session.engine().frames_per_cycle();
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jack_default_audio_sample_t *in;
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jack_latency_range_t ltc_latency;
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monotonic_cnt += nframes;
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boost::shared_ptr<Port> ltcport = session.engine().ltc_input_port();
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ltcport->get_connected_latency_range(ltc_latency, false);
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in = (jack_default_audio_sample_t*) jack_port_get_buffer (ltcport->jack_port(), nframes);
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DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC_Slave::speed_and_position - TID:%1 | latency: %2\n", ::pthread_self(), ltc_latency.max));
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if (last_timestamp == 0) {
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engine_dll_initstate = 0;
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delayedlocked++;
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}
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else if (engine_dll_initstate != transport_direction) {
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engine_dll_initstate = transport_direction;
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init_engine_dll(last_ltc_frame, session.engine().frames_per_cycle());
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}
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if (in) {
|
||||
parse_ltc(nframes, in, now + ltc_latency.max );
|
||||
if (!process_ltc(now, nframes)) {
|
||||
/* fly wheel */
|
||||
double elapsed = (now - last_timestamp) * ltc_speed;
|
||||
ltc_transport_pos = last_ltc_frame + elapsed;
|
||||
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC fly wheel elapsed: %1 @speed %2\n", elapsed, ltc_speed));
|
||||
if (!process_ltc(now, sess_pos, nframes) && ltc_speed != 0) {
|
||||
}
|
||||
}
|
||||
|
||||
if (((now - last_timestamp) > 4 * frames_per_ltc_frame) ) {
|
||||
/* interpolate position according to speed and time since last LTC-frame*/
|
||||
double speed_flt = ltc_speed;
|
||||
framecnt_t elapsed;
|
||||
if (speed_flt == 0.0f) {
|
||||
elapsed = 0;
|
||||
} else {
|
||||
/* scale elapsed time by the current LTC speed */
|
||||
if (last_timestamp && (now > last_timestamp)) {
|
||||
elapsed = (now - last_timestamp) * speed_flt;
|
||||
} else {
|
||||
elapsed = 0;
|
||||
}
|
||||
/* update engine DLL and calculate speed */
|
||||
const double e = double (last_ltc_frame + elapsed - sess_pos);
|
||||
te0 = te1;
|
||||
te1 += be * e + ee2;
|
||||
ee2 += ce * e;
|
||||
speed_flt = (te1 - te0) / double(session.engine().frames_per_cycle());
|
||||
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC engine DLL t0:%1 t1:%2 err:%3 spd:%4 ddt:%5\n", te0, te1, e, speed_flt, ee2 - session.engine().frames_per_cycle() ));
|
||||
}
|
||||
|
||||
pos = last_ltc_frame + elapsed;
|
||||
speed = speed_flt;
|
||||
current_delta = (pos - sess_pos);
|
||||
|
||||
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTCsync spd: %1 pos: %2 | last-pos: %3 elapsed: %4 delta: %5\n",
|
||||
speed, pos, last_ltc_frame, elapsed, current_delta));
|
||||
|
||||
if (last_timestamp != 0 /* && frames_in_sequence > 8*/) {
|
||||
delayedlocked = 0;
|
||||
}
|
||||
|
||||
if (last_timestamp == 0 || ((now - last_timestamp) > FLYWHEEL_TIMEOUT)) {
|
||||
DEBUG_TRACE (DEBUG::LTC, "LTC no-signal - reset\n");
|
||||
speed = ltc_speed = 0;
|
||||
reset();
|
||||
engine_dll_initstate = 0;
|
||||
speed = 0;
|
||||
pos = session.transport_frame();
|
||||
last_timestamp = 0;
|
||||
ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
|
||||
return true;
|
||||
}
|
||||
|
||||
pos = ltc_transport_pos;
|
||||
speed = ltc_speed;
|
||||
if (last_timestamp != 0 && ltc_speed != 0 && ((ltc_transport_pos < 0) || (labs(current_delta) > 10 * session.frame_rate()))) {
|
||||
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC large drift. %1\n", current_delta));
|
||||
// XXX only re-init engine DLL ?
|
||||
reset();
|
||||
engine_dll_initstate = 0;
|
||||
speed = 0;
|
||||
pos = session.transport_frame();
|
||||
return true;
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
|
@ -358,11 +532,25 @@ LTC_Slave::apparent_timecode_format () const
|
|||
return session.config.get_timecode_format();
|
||||
}
|
||||
|
||||
std::string
|
||||
std::string
|
||||
LTC_Slave::approximate_current_position() const
|
||||
{
|
||||
if (last_timestamp == 0) {
|
||||
return "--:--:--:--";
|
||||
return " --:--:--:--";
|
||||
}
|
||||
return Timecode::timecode_format_time(timecode);
|
||||
}
|
||||
|
||||
std::string
|
||||
LTC_Slave::approximate_current_delta() const
|
||||
{
|
||||
char delta[24];
|
||||
if (last_timestamp == 0 || frames_in_sequence < 3) {
|
||||
snprintf(delta, sizeof(delta), "---");
|
||||
} else {
|
||||
// TODO if current_delta > 1 frame -> display timecode.
|
||||
// delta >0 if A3's transport is _behind_ LTC
|
||||
snprintf(delta, sizeof(delta), "%+4" PRIi64 " sm", current_delta);
|
||||
}
|
||||
return std::string(delta);
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue
Block a user