Commit f72aaed9 authored by Sebastian Dröge's avatar Sebastian Dröge 🍵 Committed by GStreamer Merge Bot

timecodestamper: Add property to set the extra latency to introduce for waiting for LTC timecodes

Default to 150ms instead of 8 frames, which seems to work in the
majority of cases.
parent fdca7ebb
......@@ -67,6 +67,7 @@ enum
PROP_SET_INTERNAL_TIMECODE,
PROP_LTC_DAILY_JAM,
PROP_LTC_AUTO_RESYNC,
PROP_LTC_EXTRA_LATENCY,
PROP_LTC_TIMEOUT,
PROP_RTC_MAX_DRIFT,
PROP_RTC_AUTO_RESYNC,
......@@ -83,6 +84,7 @@ enum
#define DEFAULT_LTC_DAILY_JAM NULL
#define DEFAULT_LTC_AUTO_RESYNC TRUE
#define DEFAULT_LTC_TIMEOUT GST_CLOCK_TIME_NONE
#define DEFAULT_LTC_EXTRA_LATENCY (150 * GST_MSECOND)
#define DEFAULT_RTC_MAX_DRIFT 250000000
#define DEFAULT_RTC_AUTO_RESYNC TRUE
#define DEFAULT_TIMECODE_OFFSET 0
......@@ -275,6 +277,11 @@ gst_timecodestamper_class_init (GstTimeCodeStamperClass * klass)
"If true the LTC timecode will be automatically resynced if it drifts, "
"otherwise it will only be counted up from the last known one",
DEFAULT_LTC_AUTO_RESYNC, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_LTC_EXTRA_LATENCY,
g_param_spec_uint64 ("ltc-extra-latency", "LTC Extra Latency",
"Extra latency to introduce for waiting for LTC timecodes",
0, G_MAXUINT64, DEFAULT_LTC_EXTRA_LATENCY,
G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
g_object_class_install_property (gobject_class, PROP_LTC_TIMEOUT,
g_param_spec_uint64 ("ltc-timeout", "LTC Timeout",
"Time out LTC timecode if no new timecode was detected after this time",
......@@ -337,6 +344,7 @@ gst_timecodestamper_init (GstTimeCodeStamper * timecodestamper)
timecodestamper->set_internal_tc = NULL;
timecodestamper->ltc_daily_jam = DEFAULT_LTC_DAILY_JAM;
timecodestamper->ltc_auto_resync = DEFAULT_LTC_AUTO_RESYNC;
timecodestamper->ltc_extra_latency = DEFAULT_LTC_EXTRA_LATENCY;
timecodestamper->ltc_timeout = DEFAULT_LTC_TIMEOUT;
timecodestamper->rtc_max_drift = DEFAULT_RTC_MAX_DRIFT;
timecodestamper->rtc_auto_resync = DEFAULT_RTC_AUTO_RESYNC;
......@@ -520,6 +528,9 @@ gst_timecodestamper_set_property (GObject * object, guint prop_id,
case PROP_LTC_TIMEOUT:
timecodestamper->ltc_timeout = g_value_get_uint64 (value);
break;
case PROP_LTC_EXTRA_LATENCY:
timecodestamper->ltc_extra_latency = g_value_get_uint64 (value);
break;
case PROP_RTC_MAX_DRIFT:
timecodestamper->rtc_max_drift = g_value_get_uint64 (value);
break;
......@@ -575,6 +586,9 @@ gst_timecodestamper_get_property (GObject * object, guint prop_id,
case PROP_LTC_TIMEOUT:
g_value_set_uint64 (value, timecodestamper->ltc_timeout);
break;
case PROP_LTC_EXTRA_LATENCY:
g_value_set_uint64 (value, timecodestamper->ltc_extra_latency);
break;
case PROP_RTC_MAX_DRIFT:
g_value_set_uint64 (value, timecodestamper->rtc_max_drift);
break;
......@@ -919,11 +933,10 @@ gst_timecodestamper_query (GstBaseTransform * trans,
if (res && timecodestamper->vinfo.fps_n && timecodestamper->vinfo.fps_d) {
gst_query_parse_latency (query, &live, &min_latency, &max_latency);
if (live && timecodestamper->ltcpad) {
/* Introduce additional 8 frames of latency for LTC processing as
* the LTC library seems to usually lag behind 1-6 frames with the
* values reported back to us. */
/* TODO: Figure out how to calculate this numbers */
latency = 8 *
/* Introduce additional LTC for waiting for LTC timecodes. The
* LTC library introduces some as well as the encoding of the LTC
* signal. */
latency = timecodestamper->ltc_extra_latency *
gst_util_uint64_scale_int_ceil (GST_SECOND,
timecodestamper->vinfo.fps_d, timecodestamper->vinfo.fps_n);
min_latency += latency;
......@@ -1243,10 +1256,11 @@ gst_timecodestamper_transform_ip (GstBaseTransform * vfilter,
gst_element_get_base_time (GST_ELEMENT_CAST (timecodestamper));
GstClockTime wait_time;
/* If we have no latency yet then wait at least 8 frames durations.
* See LATENCY query handling for details. */
/* If we have no latency yet then wait at least for the LTC extra
* latency. See LATENCY query handling for details. */
if (timecodestamper->latency == GST_CLOCK_TIME_NONE) {
wait_time = base_time + running_time + 8 * frame_duration;
wait_time =
base_time + running_time + timecodestamper->ltc_extra_latency;
} else {
wait_time = base_time + running_time + timecodestamper->latency;
}
......@@ -1261,8 +1275,8 @@ gst_timecodestamper_transform_ip (GstBaseTransform * vfilter,
GST_TIME_ARGS (base_time),
GST_TIME_ARGS (running_time),
GST_TIME_ARGS (timecodestamper->latency ==
GST_CLOCK_TIME_NONE ? 8 *
frame_duration : timecodestamper->latency),
GST_CLOCK_TIME_NONE ? timecodestamper->ltc_extra_latency :
timecodestamper->latency),
GST_TIME_ARGS (gst_clock_get_time (clock))
);
clock_id = gst_clock_new_single_shot_id (clock, wait_time);
......
......@@ -85,6 +85,7 @@ struct _GstTimeCodeStamper
GDateTime *ltc_daily_jam;
gboolean ltc_auto_resync;
GstClockTime ltc_timeout;
GstClockTime ltc_extra_latency;
GstClockTime rtc_max_drift;
gboolean rtc_auto_resync;
gint timecode_offset;
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment