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.
This fixes a memleak if read_kuki_chunk is executed more than once.
Reviewed-by: Carl Eugen Hoyos <cehoyos@ag.or.at>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
If avio_read fails, the buffer can contain uninitialized values.
Reviewed-by: Carl Eugen Hoyos <cehoyos@ag.or.at>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
* commit '86dfcfd0e30d6645eea2c63c1c60a0550e7c97ea':
mov: Drop unused parameter from ff_mov_read_esds()
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Several compilers such as clang/icc/pathscale will optimize the check
pos + size < pos (assuming size > 0) into false, since signed integer
overflow is undefined behavior in C. This breaks overflow checking.
Use a safe precondition check instead.
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Specification mentions 'strg', 'mark', 'regn', 'info', .. chunks
to have data section size larger than chunk's current meaningful
content in order to reserve room for additional data.
Signed-off-by: Paul B Mahol <onemda@gmail.com>
* qatar/master:
mov_chan: Pass a separate AVIOContext for reading
af_asyncts: check return value from lavr when flushing.
mss2: simplify loop in decode_rle()
mss12: avoid unnecessary division in arith*_get_bit()
mss2: do not try to read too many palette entries
mpegvideo: set AVFrame fields to NULL after freeing the base memory
configure: Set the right cc_e flags for msvc
Merged-by: Michael Niedermayer <michaelni@gmx.at>
This fixes crashes when called from rtpdec_qt, where
AVFormatContext->pb is null, a crash present since 3bab7cd128.
Signed-off-by: Martin Storsjö <martin@martin.st>
* qatar/master:
mpc8: return more meaningful error codes.
mpc: return more meaningful error codes.
wv,mpc8: don't return apetag data in packets.
rtmp: do not warn about receiving metadata packets
x86: h264dsp: Adjust YASM #ifdefs
x86: yadif: Mark mmxext optimizations as such
h264: convert loop filter strength dsp function to yasm.
Improve descriptiveness of a number of codec and container long names
Conflicts:
libavcodec/flvdec.c
libavcodec/libopenjpegdec.c
libavformat/apetag.c
libavformat/mp3dec.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* qatar/master: (38 commits)
alac: cosmetics: general pretty-printing and comment clean up
alac: calculate buffer size outside the loop in allocate_buffers()
alac: change some data types to plain int
alac: cosmetics: rename some variables and function names
alac: multi-channel decoding support
alac: split element parsing into a separate function
alac: support a read sample size of up to 32
alac: output in planar sample format
alac: add 32-bit decoding support
alac: simplify channel interleaving
alac: use AVPacket fields directly in alac_decode_frame()
alac: fix check for valid max_samples_per_frame
alac: use get_sbits() to read LPC coefficients instead of casting
alac: move the current samples per frame to the ALACContext
alac: avoid using a double-negative when checking if the frame is compressed
alac: factor out output_size check in predictor_decompress_fir_adapt()
alac: factor out loading of next decoded sample in LPC prediction
alac: use index into buffer_out instead of incrementing the pointer
alac: simplify lpc coefficient adaptation
alac: reduce the number of local variables needed in lpc prediction
...
Conflicts:
libavcodec/alac.c
libavformat/cafdec.c
libavformat/mov.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
* qatar/master:
fix hardcoded tables compililation caused by missing math constants
lavf: Make codec_tag arrays constant
twinvq: give massive struct a name.
lavf, lavu: version bumps and APIchanges for av_gettime() move
lavfi/audio: don't set cur_buf in ff_filter_samples().
lavfi/fifo: add audio version of the fifo filter.
fifo: fix parenthesis placement.
lavfi: rename vf_fifo.c -> fifo.c
lavc: remove stats_in from AVCodecContext options table.
Conflicts:
doc/APIchanges
libavfilter/Makefile
libavfilter/allfilters.c
libavfilter/audio.c
libavfilter/fifo.c
libavformat/version.h
libavutil/avutil.h
Merged-by: Michael Niedermayer <michaelni@gmx.at>
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>
* qatar/master: (38 commits)
v210enc: remove redundant check for pix_fmt
wavpack: allow user to disable CRC checking
v210enc: Use Bytestream2 functions
cafdec: Check return value of avio_seek and avoid modifying state if it fails
yop: Check return value of avio_seek and avoid modifying state if it fails
tta: Check return value of avio_seek and avoid modifying state if it fails
tmv: Check return value of avio_seek and avoid modifying state if it fails
r3d: Check return value of avio_seek and avoid modifying state if it fails
nsvdec: Check return value of avio_seek and avoid modifying state if it fails
mpc8: Check return value of avio_seek and avoid modifying state if it fails
jvdec: Check return value of avio_seek and avoid modifying state if it fails
filmstripdec: Check return value of avio_seek and avoid modifying state if it fails
ffmdec: Check return value of avio_seek and avoid modifying state if it fails
dv: Check return value of avio_seek and avoid modifying state if it fails
bink: Check return value of avio_seek and avoid modifying state if it fails
Check AVCodec.pix_fmts in avcodec_open2()
svq3: Prevent illegal reads while parsing extradata.
remove ParseContext1
vc1: use ff_parse_close
mpegvideo parser: move specific fields into private context
...
Conflicts:
libavcodec/4xm.c
libavcodec/aacdec.c
libavcodec/h264.c
libavcodec/h264.h
libavcodec/h264_cabac.c
libavcodec/h264_cavlc.c
libavcodec/mpeg4video_parser.c
libavcodec/svq3.c
libavcodec/v210enc.c
libavformat/cafdec.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
