Currently of_output_packet() reuses the input packet, which requires its
callers to submit blank packets even on EOF, which makes the code more
complex.
It is set by the muxing code, which will not be synchronized with
encoding code after upcoming threading changes. Use an encoder-private
variable instead.
Packets submitted to the muxer now have their timebase attached to them,
so the muxer can do conversion to muxing timebase and avoid exposing it
to callers.
There is no reason to postpone it until opening the encoder. Also, abort
when the input stream is unknown, rather than disregard an explicit
request from the user.
The code will currently add a small offset to avoid exact midpoints, but
this can cause inexact results when a float timestamp is exactly
representable as an integer.
Fixes off-by-one in the first frame duration in multiple FATE tests.
Current code marks the output stream as finished and waits for a flush
packet, but that is both unnecessary and suspect, as in theory nothing
should be sent to a finished stream - not even flush packets.
Make all relevant state per-filtergraph input, rather than per-input
stream. Refactor the code to make it work and avoid leaking memory when
a single subtitle stream is sent to multiple filters.
Set them in ifilter_parameters_from_dec(), similarly to audio/video
streams. This reduces the extent to which sub2video filters need to be
treated specially.
This function should not take an InputStream, as it only uses it to get
the InputFile and the timebase. Pass those directly instead and avoid
confusion over dealing with multiple InputStreams.
This queue should be associated with a specific filtergraph input - if
a subtitle stream is sent to multiple filters then each should have its
own queue.
This code is a sub2video analogue of ifilter_send_frame(), so it
properly belongs to the filtering code.
Note that using sub2video with more than one target for a given input
subtitle stream is currently broken and this commit does not change
that. It will be addressed in following commits.
When the filtergraph has no inputs, it can be configured immediately
when all its outputs are bound to output streams. This will simplify
treating some corner cases.
This way the list of filtergraph inputs/outputs is always known after
FilterGraph creation. This will allow treating simple and complex
filtergraphs in a more uniform manner.
Currently NULL would be passed for simple filtergraphs, which would
make the filter code extract the graph description from the output
stream when needed. This is unnecessarily convoluted.
A non-limiting stream could mistakenly end up being the queue head,
which would then produce incorrect synchronization, seen e.g. in
fate-matroska-flac-extradata-update for certain number of frame threads
(e.g. 5).
Found-By: James Almer
Anton Khirnov