As a side-effect we can now actually store the line offset in the
line21dec element, and have to perform fewer transformations in the
decklink elements (which were also buggy as they assumed a single byte
triplet per meta).
Fixes the time calculations when dealing with a slaved clock (as
will occur with more than one decklink video sink), when performing
flushing seeks causing stalls in the output timeline, pausing.
Tighten up the calculations by relying solely on the internal time
(from the internal clock) for determining when to schedule display
frames instead attempting to track pause lengths from the external
clock and converting to internal time. This results in a much easier
offset calculation for choosing the output time and ensures that the
clock is always advancing when we need it to.
This is fixup to the 'monotonically increasing output timestamps' goal
in: bf849e9a69
Instead of relying on buffers after a state change to PLAYING to always start
from 0, track the amount of time we have spent outside playing but not changed
state to PAUSED.
Before this patch, if mode=auto and video-format!=auto, video-format would
always be ignored, and get set to 8bit-yuv, or if detected to be RGB444, then
it would be set to 8bit-argb. This change respects video-format if it is set
to 10bit-yuv (v210) or 8bit-bgra, even when mode=auto.
Closes#772
../sys/decklink/gstdecklinkvideosink.cpp:1006:11: error: ‘GstDecklinkVideoSink {aka struct _GstDecklinkVideoSink}’ has no member named ‘scheduled_stop_time’
self->scheduled_stop_time = start_time;
^
Decklink sometimes does not notify us through the callback that it has
stopped scheduled playback either because it was uncleanly shutdown
without an explicit stop or for unknown other reasons.
Wait on the cond for a short amount of time before checking if scheduled
playback has stopped without notification.
https://bugzilla.gnome.org/show_bug.cgi?id=797130
This is part of a much larger goal to always keep the frames we schedule to
decklink be always increasing. This also allows us to avoid using both the
sync and async frame display functions which aren't recomended to be used
together.
If the output timestatmsp is not always increasing decklink seems to hold
onto the latest frame and may cause a flash in the output if the played
sequence has a framerate less than the video output.
Scenario is play for N seconds, pause, flushing seek to some other position,
play again. Each of the play sequences would normally start at 0 with
the decklink time. As a result, the latest frame from the previous sequence
is kept alive waiting for it's timestamp to pass before either dropping
(if a subsequent frame in the new sequence overrides it) or displayed
causing the out of place frame to be displayed.
This is also supported by the debug logs from the decklink video sink
element where a ScheduledFrameCompleted() callback would not occur for
the frame until the above had happened.
It was timing related as to whether the frame was displayed based
on the decklink refresh cycle (which seems to be 16ms here),
when the frame was scheduled by the sink and the difference between
the 'time since vblank' of the two play requests (and thus start times
of scheduled playback).
https://bugzilla.gnome.org/show_bug.cgi?id=797130
Otherwise decklink seems to hold onto the latest frame and may cause a
flash in the output if the played sequence has a framerate less than the
video output.
Scenario is play for N seconds, pause, flushing seek to some other position,
play again. Each of the play sequences would normally start at 0 with
the decklink time. As a result, the latest frame from the previous sequence
is kept alive waiting for it's timestamp to pass before either dropping
(if a subsequent frame in the new sequence overrides it) or displayed
causing the out of place frame to be displayed.
This is also supported by the debug logs from the decklink video sink
element where a ScheduledFrameCompleted() callback would not occur for
the frame until the above had happened.
It was timing related as to whether the frame was displayed based
on the decklink refresh cycle (which seems to be 16ms here),
when the frame was scheduled by the sink and the difference between
the 'time since vblank' of the two play requests (and thus start times
of scheduled playback).
If the "output-cc" property is set to TRUE and there is CC present
in the VBI Ancillary Data, they will be extracted and set on the
outgoing buffer as GstVideoCaptionMeta.
Only CDP packets are supported.
https://bugzilla.gnome.org/show_bug.cgi?id=773863
There is no log of gst_decklink_com_thread () which initializes COM.
The initialization part is not valid with #ifdef MSC_VER.
Windows binaries are built with gcc.
As with other codes, it was avoidable by setting it to G_OS_WIN32
instead of MSC_VER.
https://bugzilla.gnome.org/show_bug.cgi?id=794652
There is no fixed limitation for the number of devices on the
decklink API side according to BlackMagic. Many PC motherboards
are able support 6 decklink cards each with up to 8 inputs so
a limit of 16 might well be too low.
https://bugzilla.gnome.org/show_bug.cgi?id=777239
Sometimes we might get an audio packet without a corresponding video
frame. In these cases, the stream and hardware reference timestamps
would be missing, because they're called on the video frame. Instead of
potentially breaking stuff downstream that might depend on these, we now
extrapolate them.
https://bugzilla.gnome.org/show_bug.cgi?id=792042
When we receive a video or audio buffer, we calculate the next stream
time based on the current stream time + buffer duration. If the next
buffer's stream time is after that, we issue a warning.
This happens because the stream time incoming from Decklink should be
really constant and without gaps. If there is a gap, it means that
something went wrong, e.g. the internal buffer pool is empty (too many
buffers queued up downstream).
https://bugzilla.gnome.org/show_bug.cgi?id=781776
Sometimes we might get an audio packet without a corresponding video
frame. In these cases, the stream and hardware reference timestamps
would be missing, because they're called on the video frame. Instead of
potentially breaking stuff downstream that might depend on these, we now
extrapolate them.
https://bugzilla.gnome.org/show_bug.cgi?id=792042
Not only if the video sink is set to PLAYING so far. Also give more
useful debug output about why we don't start, and don't start if already
started.
Also refactor the function to early-return instead of having a huge
if-else block over the whole function.
https://bugzilla.gnome.org/show_bug.cgi?id=790114
The Decklink and GstAudioBaseSink APIs don't fit very well together,
which causes various problems due to inaccuracies in the clock
calculations and the actual ringbuffer and GStreamer's copy getting of
sync.
Problems are audio drop-outs and A/V sync getting wrong after
pausing/seeking.
https://bugzilla.gnome.org/show_bug.cgi?id=790114
The "fields" flag is ignored because currently GStreamer doesn't support
having only top or only bottom fields inside a frame. The "drop frame"
flag is ignored because some occurrences have been spotted where it
wasn't set while it should have been. In practice, when we have 29.97 or
59.94 FPS, it's always drop-frame.
https://bugzilla.gnome.org/show_bug.cgi?id=790112
When we receive a video or audio buffer, we calculate the next stream
time based on the current stream time + buffer duration. If the next
buffer's stream time is after that, we issue a warning.
This happens because the stream time incoming from Decklink should be
really constant and without gaps. If there is a gap, it means that
something went wrong, e.g. the internal buffer pool is empty (too many
buffers queued up downstream).
https://bugzilla.gnome.org/show_bug.cgi?id=781776
