This fixes mpeg2video stream copies to mpeg muxer like this:
ffmpeg -i xdcamhd.mxf -c:v copy output.mpg
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Fixes: left shift of negative value -695
Fixes: 19232/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG1VIDEO_fuzzer-5702856963522560
Fixes: 19555/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_MPEG1VIDEO_fuzzer-5741218147598336
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Though this patch to fix ticket #6668, I belive it
is unnecessary to set SLICE_FLAG_ALLOW_FIELD flag to other
hwaccels(dxva, vdpau, etc). Please also refer the orginal comment
of 9cb150c9ab
Should also fix ticket #8442.
Signed-off-by: Zhong Li <zhong.li@intel.com>
Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>
The MPEG-1/2 decoder uses avpriv_find_start_code to search for start
codes and worked with the resulting start code before checking that it
is really a start code of a slice. In particular, if the picture is so
big that a slice_vertical_position_extension is present, it added the
slice_vertical_position_extension as if it had a slice. Then a left
shift is performed, without making sure that the value to be shifted is
nonnegative.
Afterwards the end result is checked, but even if a start code of a
non-slice has been found, it might pass these checks: If
slice_vertical_position_extension is present a start code <
SLICE_MIN_START_CODE can lead to a macroblock-row index that appears
valid. Furthermore, the left shift might make an invalid start code
appear valid by discarding the highest bit.
This has been fixed by checking directly after avpriv_find_start_code
has returned.
Fixes ticket #8162 (which is about the undefined left shifts).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
For B field pictures, the spec says,
> The prediction shall be made from the field of the same parity as the field being predicted.
I did it.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This includes a pointer to the associated hwaccel for decoders using
hwaccels - these will be used later to implement the hwaccel setup
without needing a global list.
Also added is a new file listing all hwaccels as external declarations -
this will be used later to generate the hwaccel list at configure time.
This is mostly straight-forward. The weird part is that it should
just work for mpeg1, but I see corruption in my test cases, so I'm
going to try and fix that separately.
In the past XvMC forced simple_idct since
it was using FF_IDCT_PERM_NONE.
However now we have SIMD variants of simple_idct that
are using FF_IDCT_PERM_TRANSPOSE and if they are selected
XvMC would get coefficients in the wrong order.
The patch creates new FF_IDCT_NONE that
is used only for this kind of hardware decoding
and that fallbacks to the old C only simple idct.
Signed-off-by: Ivan Kalvachev <ikalvachev@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This also adds support to avconv (which is trivial due to the new
hwaccel API being generic enough).
The new decoder setup code in dxva2.c is significantly based on work by
Steve Lhomme <robux4@gmail.com>, but with heavy changes/rewrites.
Merges Libav commit f9e7a2f95a.
Also adds untested VP9 support.
The check for DXVA2 COBJs is removed. Just update your MinGW to
something newer than a 5 year old release.
Signed-off-by: Diego Biurrun <diego@biurrun.de>
671/clusterfuzz-testcase-4990381827555328
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
For field picture, the first_field is set based on its previous value.
Before this commit, first_field is set when reading the picture
coding extension. However, in corrupted files there may be multiple
picture coding extension headers, so the final value of first_field that
is actually used during decoding can be wrong. That can lead to various
undefined behaviour, like predicting from a non-existing field.
Fix this problem, by setting first_field in mpeg_field_start(), which
should be called exactly once per field.
CC: libav-stable@libav.org
Bug-ID: 999
This decreases the amount of computations and memory needed for analysing mpeg1/2 streams
the properties update is moved from code that is skiped if skip_frame is set
to code that is not skiped so the change doesnt loose that
from being executed
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Otherwise another frame gets referenced into picture, triggering an assert
(from commit 13aae8) in av_frame_ref.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
This allows untangling the eatqi decoder from the MPEG-1 decoder.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Signed-off-by: Diego Biurrun <diego@biurrun.de>
