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>
Up until now, we had a PacketList structure which is actually
a PacketListEntry; a proper PacketList did not exist
and all the related functions just passed pointers to pointers
to the head and tail elements around. All these pointers were
actually consecutive elements of their containing structs,
i.e. the users already treated them as if they were a struct.
So add a proper PacketList struct and rename the current PacketList
to PacketListEntry; also make the functions use this structure
instead of the pair of pointers.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The packet given to muxers is not used afterwards; it is always
unreferenced by libavformat. Ergo muxers are allowed to keep
the references in the packets and e.g. move the ownership to
a packet list. This is what this commit does.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It only uses an AVIOContext and an AVBPrint.
When doing so, it turned out that several non-users of
ff_read_line_to_bprint_overwrite() and ff_bprint_to_codecpar_extradata()
relied on libavformat/internal.h to include bprint.h or avstring.h
for them. In order to avoid a repeat of this and in order to reduce
unnecessary dependencies, a forward declaration of struct AVBPrint is
used instead of including bprint.h.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
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>
The next pointer is kept at the end for backwards compatability until the
major bump, when it should ideally be moved at the front.
Signed-off-by: James Almer <jamrial@gmail.com>
The FLAC muxer currently stores an attached picture corresponding to an
AVStream in AVStream.priv_data. The AVPacket contained therein is
unreferenced after it has been written. The AVPacket structure itself is
then freed generically as AVStream.priv_data.
And this can lead to memleaks if an attached picture is not written:
It might be because the trailer is never written or because writing
a previous attached picture failed in case error_recognition is set
to explode.
Therefore free the packets properly (i.e. with av_packet_free())
in the muxer's deinit function.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
And replace the flags parameter with a function callback that can be used to
copy the contents of the packet (e.g, av_packet_ref and av_packet_copy_props).
Signed-off-by: James Almer <jamrial@gmail.com>
Up until now ff_vorbiscomment_write() used the bytestream API to write
VorbisComments. Therefore the caller had to provide a sufficiently large
buffer to write the output.
Yet two of the three callers (namely the FLAC and the Matroska muxer)
actually want the output to be written via an AVIOContext; therefore
they allocated buffers of the right size just for this purpose (i.e.
they get freed immediately afterwards). Only the Ogg muxer actually
wants a buffer. But given that it is easy to wrap a buffer into an
AVIOContext this commit changes ff_vorbiscomment_write() to use an
AVIOContext for its output.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
ff_vorbiscomment_write() used an AVDictionary ** parameter for a
dictionary whose contents ought to be written; yet this can be replaced
by AVDictionary * since commit 042ca05f0fdc5f4d56a3e9b94bc9cd67bca9a4bc;
and this in turn can be replaced by const AVDictionary * to indicate
that the dictionary isn't modified; the latter also applies to
ff_vorbiscomment_length().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
It is a small buffer of a known, fixed size and so it should simply be
put into the muxer's context.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
An AVStream's codecpar is supposed to be filled by the caller before
avformat_write_header(); if the CodecParameters change, the caller
should signal this via packet side data, but not touch the AVStream's
codecpar.
The FLAC muxer checks for packet side data containing updated extradata,
yet if nothing has arrived by the time the trailer is written, the
already written extradata is overwritten by the very same extradata
again, unless the output is unseekable, in which case a warning that the
FLAC header can't be rewritten is emitted.
This commit changes this by only trying to rewrite the extradata if a
new streaminfo arrived via packet side data. Only then is a warning
emitted in case the output is unseekable.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
A too big picture will case the muxer to write a truncated block size (uint24)
causing the output file to be corrupt.
How to reproduce:
Write a file with truncated block size:
ffmpeg -y -f lavfi -i sine -f lavfi -i color=red:size=2400x2400 -map 0🅰️0 -map 1✌️0 -c✌️0 bmp -disposition:1 attached_pic -t 1 test.flac
Try to decode:
ffmpeg -i test.flac test.wav
Signed-off-by: Mattias Wadman <mattias.wadman@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
It is supposed to be a flag. The only currently defined value is
AVIO_SEEKABLE_NORMAL, but other ones may be added in the future.
However all the current lavf code treats this field as a bool (mainly
for historical reasons).
Change all those cases to properly check for AVIO_SEEKABLE_NORMAL.
Currently, AVStream contains an embedded AVCodecContext instance, which
is used by demuxers to export stream parameters to the caller and by
muxers to receive stream parameters from the caller. It is also used
internally as the codec context that is passed to parsers.
In addition, it is also widely used by the callers as the decoding (when
demuxer) or encoding (when muxing) context, though this has been
officially discouraged since Libav 11.
There are multiple important problems with this approach:
- the fields in AVCodecContext are in general one of
* stream parameters
* codec options
* codec state
However, it's not clear which ones are which. It is consequently
unclear which fields are a demuxer allowed to set or a muxer allowed to
read. This leads to erratic behaviour depending on whether decoding or
encoding is being performed or not (and whether it uses the AVStream
embedded codec context).
- various synchronization issues arising from the fact that the same
context is used by several different APIs (muxers/demuxers,
parsers, bitstream filters and encoders/decoders) simultaneously, with
there being no clear rules for who can modify what and the different
processes being typically delayed with respect to each other.
- avformat_find_stream_info() making it necessary to support opening
and closing a single codec context multiple times, thus
complicating the semantics of freeing various allocated objects in the
codec context.
Those problems are resolved by replacing the AVStream embedded codec
context with a newly added AVCodecParameters instance, which stores only
the stream parameters exported by the demuxers or read by the muxers.
Use it instead of checking CODEC_FLAG_BITEXACT in the first stream's
codec context.
Using codec options inside lavf is fragile and can easily break when the
muxing codec context is not the encoding context.
Allows a user to control the amount, if any, of padding they want added
to the file. If set to zero the block will not be written at all. If
set to some positive number four more bytes will be added to the file
due to the small header required for the block.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Since 596e5d4783, this is not necessary anymore. It also allows to
actually disable the flushing, improving write performance (but
possibly giving worse latency in real-time streaming).
Signed-off-by: Martin Storsjö <martin@martin.st>
Also add missing trailing commas, break long codec_tag lines and
add spaces in codec_tag declarations.
Signed-off-by: Martin Storsjö <martin@martin.st>
Andreas Rheinhardt
Martin Storsjö
Vittorio Giovara
James Almer
Andreas Rheinhardt
Marton Balint
Mattias Wadman
Paul B Mahol
Rodger Combs
Anton Khirnov
Clément Bœsch
Michael Niedermayer
Clément Bœsch
James Darnley
Justin Ruggles
Clément Bœsch
Diego Biurrun
Mans Rullgard