This commit enables sending UDP packets in a background thread with specified delay.
When sending packets without a delay some devices with small RX buffer
( MAG200 STB, for example) will drop tail packets in bursts causing
decoding errors.
To use it specify "fifo_size" with "packet_gap" .
The output url will looks like udp://xxx:yyy?fifo_size=<output fifo
size>&packet_gap=<delay in usecs>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This allows callers with avio write callbacks to get the bytestream
positions that correspond to keyframes, suitable for live streaming.
In the simplest form, a caller could expect that a header is written
to the bytestream during the avformat_write_header, and the data
output to the avio context during e.g. av_write_frame corresponds
exactly to the current packet passed in.
When combined with av_interleaved_write_frame, and with muxers that
do buffering (most muxers that do some sort of fragmenting or
clustering), the mapping from input data to bytestream positions
is nontrivial.
This allows callers to get directly information about what part
of the bytestream is what, without having to resort to assumptions
about the muxer behaviour.
One keyframe/fragment/block can still be split into multiple (if
they are larger than the aviocontext buffer), which would call
the callback with e.g. AVIO_DATA_MARKER_SYNC_POINT, followed by
AVIO_DATA_MARKER_UNKNOWN for the second time it is called with
the following data.
Signed-off-by: Martin Storsjö <martin@martin.st>
It is impossible to pass "aspect" parameter to encoder from ffmpeg CLI
because option from lavc/options_table.h is eclipsed by option with same
name in ffmpeg_opt.c, which has different meaning (DAR, not SAR).
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The new function behaves the same as av_log_format_line, but also forwards
the return value from the underlying snprintf call. This will allow
callers to accurately determine the size requirements for the line buffer.
Signed-off-by: Andreas Weis <github@ghulbus-inc.de>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Adds per slave option 'onfail' to the tee muxer allowing an output to
fail, so other slave outputs can continue.
Reviewed-by: Nicolas George <george@nsup.org>
Signed-off-by: Jan Sebechlebsky <sebechlebskyjan@gmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>
Until now, the decoding API was restricted to outputting 0 or 1 frames
per input packet. It also enforces a somewhat rigid dataflow in general.
This new API seeks to relax these restrictions by decoupling input and
output. Instead of doing a single call on each decode step, which may
consume the packet and may produce output, the new API requires the user
to send input first, and then ask for output.
For now, there are no codecs supporting this API. The API can work with
codecs using the old API, and most code added here is to make them
interoperate. The reverse is not possible, although for audio it might.
From Libav commit 05f66706d1.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Add number of input and output frames to possible variables.
Add option eval to reevaluate coordinate expressions during
initialization or for every frame.
Add a filter to scan the top lines of video frames for vertical interval
timecode (VITC) information and attach it as metadata keys.
Signed-off-by: Tobias Rapp <t.rapp@noa-archive.com>
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Moritz Barsnick <barsnick@gmx.net>
Signed-off-by: James Almer <jamrial@gmail.com>
Show example which draws text at a random position, and switches positions every 30 seconds
Signed-off-by: Mulvya <mulvya@gmail.com>
Signed-off-by: Lou Logan <lou@lrcd.com>