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.
* commit '41ed749fe987e60b0485fa721ad869590651324d':
ogg: Do not try to use the parser if it is not present
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>
* commit '2f3fadfbe3c6ad52fad5c614b6067c5401227959':
lavc,lavf: switch to the new vorbis parse API
Conflicts:
libavformat/oggparsevorbis.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* commit '5e80fb7ff226f136dbcf3fed00a2966bf8e9bd70':
lavc: add a public API for parsing vorbis packets.
Conflicts:
doc/APIchanges
libavcodec/Makefile
libavcodec/version.h
libavcodec/vorbis_parser.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* commit '6896f95b2483e52e717e2c75a4fd24fcb0e14b67':
vorbis_parser: add an AV prefix to VorbisParseContext
Conflicts:
libavcodec/vorbis_parser.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Originally, AVFormatContext and a metadata dict were provided to ff_vorbis_comment(),
but this presented issues if an AVStream was being updated or the metadata on
AVFormatContext wasn't actually being updated. To remedy this, ff_vorbis_stream_comment()
explicitly updates a stream's metadata and sets any necessary flags.
ff_vorbis_comment() does not modify any flags, and any calls to it that update
AVFormatContext's metadata (just a single call) must also update
AVFormatContext.event_flags after detecting any metadata changes to the provided
dictionary, as signaled by a positive return value.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Fixes out of array read
Fixes: 34260c7981118fb38fba61809bf4dd5a-asan_heap-oob_93b923_1508_cov_951051643_DivX640x480_oggvorbis.avi
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
If a special comment packet shows up in the middle of the stream, we
should extract it out into the vorbis stream metadata dictionary.
Also, if there is metadata in the packet on the way in, it might linger
since we only add data to the dictionary causing stale metadata to be
inserted into the stream. Instead, clear it to remove any doubt about
what is new and old.
Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Currently, if there are multiple 'performer' tags, the last one is the
only one which appears. Instead, join them with a semicolon.
Signed-off-by: Ben Boeckel <mathstuf@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
* commit 'c18375ec8040a9fe0f186b2033dc975883143758':
oggvorbisdec: add support for embedded cover art
Conflicts:
libavformat/oggparsevorbis.c
See: 193782216f
Merged-by: Michael Niedermayer <michaelni@gmx.at>
When av_reallocp fails, the associated variables that keep track of
the number of elements in the array (and in some cases, the
separate number of allocated elements) need to be reset.
Not all of these might technically be needed, but it's better to
reset them if in doubt, to make sure variables don't end up
conflicting.
Signed-off-by: Martin Storsjö <martin@martin.st>
It is possible to have an initial broken header and then valid packets.
Reported-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
