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.
ff_get_wav_header is reading data from a WAVE file and then uses it
(without validation) to malloc a buffer. It then proceeded to read
data into the buffer, without verifying that the allocation succeeded.
To address this, change ff_get_wav_header to return an error if
allocation failed, and adapted all calling code to handle that error.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Passing an explicit filename to this command is only necessary if the
documentation in the @file block refers to a file different from the
one the block resides in.
Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk
Otherwise doxygen complains about ambiguous filenames when files exist
under the same name in different subdirectories.
Originally committed as revision 16912 to svn://svn.ffmpeg.org/ffmpeg/trunk
The name offset_t is easily confused with the standard off_t type and
*_t is POSIX reserved namespace if any POSIX header is included.
Originally committed as revision 15533 to svn://svn.ffmpeg.org/ffmpeg/trunk
Consistently apply this rule: the guard name is obtained from the
filename by stripping the leading "lib", converting '/' and '.' to
'_' and uppercasing the resulting name. Guard names in the root
directory have to be prefixed by "FFMPEG_".
Originally committed as revision 15120 to svn://svn.ffmpeg.org/ffmpeg/trunk
when building doxygen docs
patch by mark cox melbournemark plus ffmpeg minus devel chez gmail dot com
Originally committed as revision 8866 to svn://svn.ffmpeg.org/ffmpeg/trunk
stream id that AVI wants for MSMPEG4V3 doesn't work for ASF. I have
added a flag to indicate that certain tags should not be used in ASF
streams. I think that this is the wrong solution (just adding a flag
for ASF), but it does work.
Originally committed as revision 1112 to svn://svn.ffmpeg.org/ffmpeg/trunk
Anton Khirnov
Luca Barbato
Diego Biurrun
Peter Ross
Justin Ruggles
Victor Vasiliev
Max Horn
Mans Rullgard
Francesco Lavra
Stefano Sabatini
Carl Eugen Hoyos
Daniel Verkamp
Mark Cox
Michael Niedermayer
Fabrice Bellard
Zdenek Kabelac
Roman Shaposhnik
Philip Gladstone