This commit tests it in a way that automatically checks
that using av_dict_iterate() is equivalent to using
av_dict_get() with key "" and AV_DICT_IGNORE_SUFFIX.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Untested with "non fuzzed" samples as i have no such file
The reference 5.6.0 decoder appears to also have undefined behavior in the lossless codepath for this
Fixes: shift exponent 32 is too large for 32-bit type 'int'
Fixes: 50930/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_WAVPACK_fuzzer-6319201949712384
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
The Encoding field (and the \fe tag) allows to limit font selection to
only those fonts declaring support for the specified codepage in their
OS/2's table "Code Page Character Range" field.
Particularly, Encoding=0 means only font's declaring support for "ANSI",
or rather "Latin (Western European)", are allowed to be selected.
Specifying Encoding=1 allows all fonts to be considered.
We do not want to limit font selection, so specify Encoding=1.
NB: at the time of writing libass only partially supports this field,
thus hiding the issue in any libass-based renderer. A VSFilter-based
DirectShow filter or XySubFilter will reveal the issue when a font not
declaring support for latin characters is specified in a style.
Colour values used in ASS files without a "YCbCr Matrix" header set to
"None" are subject to colour mangling, due to how ASS was historically
conceived. A more in-depth description can be found in the documetation
inside libass' public ass_types.h header. The important part is, if this
header is not set to "None", the final output colours can deviate from
the literal value specified in the file. When converting from non-ASS
formats we do not want any colour shift to happen, so let's set the
appropiate header.
NB: ffmpeg's subtitle filter, does not follow libass' documentation
regarding colour mangling, thus hiding the bug. Anything based on
VSFilter, XySubFilter or e.g. mpv do and might show the issue.
(Of course native ASS subs, which _do_ rely on colour mangling won't
work properly with the subtitle filter, but this can be fixed another
time)
There is no v4 ASS. There are versions 1 to 4 of SSA (with only v4
being supported by softsub renderers), ASS which declares itself as v4+
or v4.00+, and the rarely used v4++/v4.00++, which isn't fully supported
by libass.
As reflected by the [V4+ Styles] section header, FFmpeg uses ASS, not
SSA v4, so adjust the comment accordingly.
avx512 on Skylake-X (Xeon D-2123IT):
1.19x faster (970±91.2 vs. 817±104.4 decicycles) compared with avx2
avx512icl on Ice Lake (Xeon Silver 4316):
2.52x faster (1350±5.3 vs. 535±9.5 decicycles) compared with avx2
