Currently, the decoder checks the 128th value of the 4th quant table during
while deriving the context on each sample, in order to speed itself up. This
is due to relying on the behavior of FFmpeg's FFV1 encoder, in which if that
value is zero, the entire 4th and 5th quant tables are assumed to be entirely
zero.
This does not match the FFV1 spec, which has no such restriction, and after
some discussion, it was decided to fix FFmpeg to abide by the spec, rather
than change the spec.
We will now check whether the 4th and 5th quant tables are zero properly,
by checking the 128th valye of both tables (which means they are zero due
to the way they're coded in the bitstream).
For further context, the FFV1 issue in question is located at:
https://github.com/FFmpeg/FFV1/issues/169
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Fixes: Assertion failure
Fixes: 19753/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_PGSSUB_fuzzer-5688461843759104
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This patch rewrites the innermost loop of ff_yuv2planeX_8_neon to avoid zips and
horizontal adds by using fused multiply adds. The patch also uses ld1r to load
one element and replicate it across all lanes of the vector. The patch also
improves the clipping code by removing the shift right instructions and
performing the shift with the shift-right narrow instructions.
I see 8% difference on an m6g instance with neoverse-n1 CPUs:
$ ffmpeg -nostats -f lavfi -i testsrc2=4k:d=2 -vf bench=start,scale=1024x1024,bench=stop -f null -
before: t:0.014015 avg:0.014096 max:0.015018 min:0.013971
after: t:0.012985 avg:0.013013 max:0.013996 min:0.012818
Tested with `make check` on aarch64-linux.
Signed-off-by: Sebastian Pop <spop@amazon.com>
Reviewed-by: Clément Bœsch <u@pkh.me>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
ff_filter_frame() always frees the frame in case of error, so we don't
need to free the frame after ff_filter_frame() fails.
Fix CID 1457230.
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
In case of failure, all the successfully set entries are stored in
*pm. We need to manually free the created dictionary to avoid
memory leak.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
In case of failure, all the successfully set entries are stored in
*pm. We need to manually free the created dictionary to avoid
memory leak.
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
In case of failure, all the successfully set entries are stored in
*pm. We need to manually free the created dictionary to avoid
memory leak.
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
In case of failure, all the successfully set entries are stored in
*pm. We need to manually free the created dictionary to avoid
memory leak.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Jun Zhao <barryjzhao@tencent.com>
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>
This will likely also fix CID 1452562, a false positive resulting from
Coverity thinking that av_dict_set() automatically frees its key and
value parameters (even without the AV_DICT_DONT_STRDUP_* flags).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The Matroska muxer currently does not check the return value of
ff_isom_write_hvcc(), the function used to write mp4-style
HEVC-extradata as Matroska also uses it. This was intentionally done in
7a5356c72 to allow remuxing from mpeg-ts.
But if ff_isom_write_hvcc() fails, it has not output anything and the
file ends up without CodecPrivate and, if the input was Annex B, with
Annex B data, which is against the spec. So check the return value
again.
The underlying issue of not having extradata seems to have been fixed by
the introduction of the extract_extradata bitstream filter.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Reviewed-by: "mypopy@gmail.com" <mypopy@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
to its actual behaviour: That it uses the least amount of bytes unless
overridden.
The current documentation leaves it undefined how many bytes will be used
when no number to use has been given explicitly. But several estimates
(used to write EBML Master elements with a small length field) require
this number to be the least amount of bytes to work. Therefore change
the documentation; and remove a comment about writing length fields
indicating "unkown length". It has been outdated since 0580a122.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
