AVOutputFormat has default codecs for audio, video and subtitle
and often these are the only codecs of this type allowed.
So add a flag to AVOutputFormat so that this can be checked generically.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
More exactly: Not more than one stream of each type for which
a default codec (i.e. AVOutputFormat.(audio|video|subtitle)_codec)
is set; for those types for which no such codec is set (or for
which no designated default codec in AVOutputFormat exists at all)
no streams are permitted.
Given that with this flag set the default codecs become more important,
they are now set explicitly to AV_CODEC_ID_NONE for "unset";
the earlier code relied on AV_CODEC_ID_NONE being equal to zero,
so that default static initialization set it accordingly;
but this is not how one is supposed to use an enum.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This commit does for AVOutputFormat what commit
20f9727018 did for AVCodec:
It adds a new type FFOutputFormat, moves all the internals
of AVOutputFormat to it and adds a now reduced AVOutputFormat
as first member.
This does not affect/improve extensibility of both public
or private fields for muxers (it is still a mess due to lavd).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
This is possible now that the next-API is gone.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: James Almer <jamrial@gmail.com>
To make it consistent with other muxers.
The user can still control the generic flushing behaviour after write_header
(same way as after packets) using the -flush_packets option, the default
typically means to flush unless a non-streamed file output is used.
Therefore this change should have no adverse effect on streaming, even if it is
assumed that the first packet has a clean buffer, so small seekbacks within the
output buffer work even when the IO context is not seekable.
Signed-off-by: Marton Balint <cus@passwd.hu>
Not requiring this can end up producing hilariously broken files
together with -c:s copy (e.g. a webvtt file containing binary subtitle data).
Signed-off-by: Simon Thelen <ffmpeg-dev@c-14.de>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Based off the srt encoder. The following features are unimplemented:
- fonts, colors, sizes
- alignment and positioning
The rest works well. For example, use ffmpeg to convert subtitles into the .vtt format:
ffmpeg -i input.srt output.vtt
Signed-off-by: Aman Gupta <ffmpeg@tmm1.net>
Signed-off-by: Clément Bœsch <u@pkh.me>
Andreas Rheinhardt