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LTC Slave, add support for variable framerates

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git-svn-id: svn://localhost/ardour2/branches/3.0@13273 d708f5d6-7413-0410-9779-e7cbd77b26cf
This commit is contained in:
Robin Gareus 2012-10-14 16:17:42 +00:00
parent 96f035e629
commit f6b9572bfd
2 changed files with 119 additions and 10 deletions
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8
libs/ardour/ardour/slave.h
View File

@ -340,12 +340,14 @@ public:
int parse_ltc(const jack_nframes_t, const jack_default_audio_sample_t * const, const framecnt_t);
bool process_ltc(framepos_t, framecnt_t);
void init_ltc_dll(framepos_t, double);
void detect_ltc_fps(int, bool);
Session& session;
bool did_reset_tc_format;
Timecode::TimecodeFormat saved_tc_format;
LTCDecoder *decoder;
Timecode::Time timecode;
double frames_per_ltc_frame;
framecnt_t last_timestamp;
@ -353,6 +355,12 @@ public:
framepos_t ltc_transport_pos;
double ltc_speed;
int ltc_detect_fps_cnt;
int ltc_detect_fps_max;
Timecode::TimecodeFormat ltc_timecode;
Timecode::TimecodeFormat a3e_timecode;
bool printed_timecode_warning;
/* DLL - chase MTC */
double t0; ///< time at the beginning of the MTC quater frame
double t1; ///< calculated end of the MTC quater frame

121
libs/ardour/ltc_slave.cc
View File

@ -42,10 +42,20 @@ using namespace Timecode;
LTC_Slave::LTC_Slave (Session& s)
: session (s)
{
frames_per_ltc_frame = 1920.0; // samplerate / framerate
frames_per_ltc_frame = session.frames_per_timecode_frame();
timecode.rate = session.timecode_frames_per_second();
timecode.drop = session.timecode_drop_frames();
printf("LTC initial rate: %f %f\n", timecode.rate, frames_per_ltc_frame);
ltc_transport_pos = 0;
ltc_speed = 1.0;
last_timestamp = 0;
ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
ltc_timecode = timecode_60; // track changes of LTC timecode
a3e_timecode = timecode_60; // track canges of Ardour's timecode
printed_timecode_warning = false;
decoder = ltc_decoder_create((int) frames_per_ltc_frame, 128 /*queue size*/);
}
@ -81,7 +91,7 @@ LTC_Slave::seekahead_distance () const
bool
LTC_Slave::locked () const
{
return true;
return true; // TODO check if >2 sequential LTC frames have been received
}
bool
@ -105,10 +115,78 @@ LTC_Slave::parse_ltc(const jack_nframes_t nframes, const jack_default_audio_samp
return 0;
}
void
LTC_Slave::detect_ltc_fps(int frameno, bool df)
{
double detected_fps = 0;
if (frameno > ltc_detect_fps_max)
{
ltc_detect_fps_max = frameno;
}
ltc_detect_fps_cnt++;
if (ltc_detect_fps_cnt > 60)
{
if (ltc_detect_fps_cnt > ltc_detect_fps_max
&& ( ceil(timecode.rate) != (ltc_detect_fps_max + 1)
|| timecode.drop != df
)
)
{
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC detected FPS %1%2",
ltc_detect_fps_max + 1, timecode.drop ? "df" : ""));
detected_fps = ltc_detect_fps_max + 1;
if (df) {
/* LTC df -> indicates fractional framerate */
detected_fps = detected_fps * 1000.0 / 1001.0;
}
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC detected FPS: %1%2\n", detected_fps, df?"df":"ndf"));
}
ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
}
/* when changed */
if (detected_fps != 0 && (detected_fps != timecode.rate || df != timecode.drop)) {
timecode.rate = detected_fps;
timecode.drop = df;
frames_per_ltc_frame = double(session.frame_rate()) / timecode.rate;
DEBUG_TRACE (DEBUG::LTC, string_compose ("LTC reset to FPS: %1%2 ; audio-frames per LTC: %3\n",
detected_fps, df?"df":"ndf", frames_per_ltc_frame));
last_timestamp = 0; // re-init
}
/* poll and check session TC */
if (1) {
TimecodeFormat tc_format = apparent_timecode_format();
TimecodeFormat cur_timecode = session.config.get_timecode_format();
if (Config->get_timecode_sync_frame_rate()) {
/* enforce time-code */
if (!did_reset_tc_format) {
saved_tc_format = cur_timecode;
did_reset_tc_format = true;
}
if (cur_timecode != tc_format) {
warning << _("Session and LTC framerate mismatch.") << endmsg;
}
session.config.set_timecode_format (tc_format);
} else {
/* only warn about TC mismatch */
if (ltc_timecode != tc_format) printed_timecode_warning = false;
if (a3e_timecode != cur_timecode) printed_timecode_warning = false;
if (cur_timecode != tc_format && ! printed_timecode_warning) {
warning << _("Session and LTC framerate mismatch.") << endmsg;
printed_timecode_warning = true;
}
}
ltc_timecode = tc_format;
a3e_timecode = cur_timecode;
}
}
bool
LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
{
Time timecode;
bool have_frame = false;
framepos_t sess_pos = session.transport_frame(); // corresponds to now
@ -120,7 +198,8 @@ LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
while (ltc_decoder_read(decoder,&frame)) {
SMPTETimecode stime;
ltc_frame_to_time(&stime, &frame.ltc, 0);
#if 1
#if 0 // Devel/Debug
fprintf(stdout, "LTC %02d:%02d:%02d%c%02d | %8lld %8lld%s\n",
stime.hours,
stime.mins,
@ -135,8 +214,8 @@ LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
timecode.negative = false;
timecode.subframes = 0;
timecode.drop = (frame.ltc.dfbit)? true : false;
timecode.rate = 25.0; // XXX
/* set timecode.rate and timecode.drop: */
detect_ltc_fps(stime.frame, (frame.ltc.dfbit)? true : false);
/* when a full LTC frame is decoded, the timecode the LTC frame
* is referring has just passed.
@ -160,7 +239,11 @@ LTC_Slave::process_ltc(framepos_t now, framecnt_t nframes)
timecode.frames = stime.frame;
framepos_t ltc_frame;
session.timecode_to_sample (timecode, ltc_frame, true, false);
Timecode::timecode_to_sample (timecode, ltc_frame, true, false,
double(session.frame_rate()),
session.config.get_subframes_per_frame(),
session.config.get_timecode_offset_negative(), session.config.get_timecode_offset()
);
double poff = (frame.off_end - now);
@ -207,6 +290,7 @@ LTC_Slave::init_ltc_dll(framepos_t tme, double dt)
/* main entry point from session_process.cc
* called from jack_process callback context
* so it is OK to use jack_port_get_buffer() etc
*/
bool
LTC_Slave::speed_and_position (double& speed, framepos_t& pos)
@ -238,6 +322,7 @@ LTC_Slave::speed_and_position (double& speed, framepos_t& pos)
speed = ltc_speed = 0;
pos = session.transport_frame();
last_timestamp = 0;
ltc_detect_fps_cnt = ltc_detect_fps_max = 0;
return true;
}
@ -250,12 +335,28 @@ LTC_Slave::speed_and_position (double& speed, framepos_t& pos)
Timecode::TimecodeFormat
LTC_Slave::apparent_timecode_format () const
{
/* XXX to be computed, determined from incoming stream */
return timecode_25;
if (timecode.rate == 24 && !timecode.drop)
return timecode_24;
else if (timecode.rate == 25 && !timecode.drop)
return timecode_25;
else if (rint(timecode.rate * 100) == 2997 && !timecode.drop)
return timecode_2997;
else if (rint(timecode.rate * 100) == 2997 && timecode.drop)
return timecode_2997drop;
else if (timecode.rate == 30 && timecode.drop)
return timecode_2997drop; // timecode_30drop; // LTC counting to 30 frames w/DF *means* 29.97 df
else if (timecode.rate == 30 && !timecode.drop)
return timecode_30;
/* XXX - unknown timecode format */
return session.config.get_timecode_format();
}
std::string
LTC_Slave::approximate_current_position() const
{
return "88:88:88:88";
if (last_timestamp == 0) {
return "--:--:--:--";
}
return Timecode::timecode_format_time(timecode);
}