Before this commit, the input in get_pixels and get_pixels_unaligned
has been treated inconsistenly:
- The generic code treated 9, 10, 12 and 14 bits as 16bit input
(these bits correspond to what FFmpeg's dsputils supported),
everything with <= 8 bits as 8 bit and everything else as 8 bit
when used via AVDCT (which exposes these functions and purports
to support up to 14 bits).
- AARCH64, ARM, PPC and RISC-V, x86 ignore this AVDCT special case.
- RISC-V also ignored the restriction to 9, 10, 12 and 14 for its
16bit check and treated everything > 8 bits as 16bit.
- The mmi MIPS code treats everything as 8 bit when used via
AVDCT (this is certainly broken); otherwise it checks for <= 8 bits.
The msa MIPS code behaves like the generic code.
This commit changes this to treat 9..16 bits as 16 bit input,
everything else as 8 bit (the former because it makes sense,
the latter to preserve the behaviour for external users*).
*: The only internal user of AVDCT (the spp filter) always
uses 8, 9 or 10 bits.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Fixes segfaults on systems where PixblockDSPContext.get_pixels
really requires to be properly aligned (e.g. ARMv7).
Before this commit input created by
-filter_complex nullsrc=s=740x576:r=25,format=yuv420p,crop=w=720:x=2
led to crashes.
(The unaligned strides are in violation of the AVFrame.linesize
documentation, unaligned pointers itself do not seem to be
prohibited for encoders.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The code uses int, unsigned int and uint16_t to store num_entry_point_offsets
This limits it to the smallest of the 3.
Alternatively uint16_t can be changed and then a larger limit used.
A Check will still be needed.
Fixes: 391974932/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_HEVC_fuzzer-5966648879677440
Fixes: signed integer overflow: 2147483647 + 1 cannot be represented in type 'int'
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: out of array access
Fixes: 394638693/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_SPEEX_fuzzer-4868142996455424
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
It invalidates (removes by duplicates) AVCodecContext.extradata
and AVCodecContext.coded_side_data which is quite surprising
and leads to bugs like #11617 where an AVCPBProperties
is used after it has been freed in ff_dovi_configure().
Reported-by: Ayose
Reviewed-by: Niklas Haas <ffmpeg@haasn.xyz>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This happens on systems where get_pixels really needs
to be properly aligned, like ARMV7 or RISC-V. For these
systems, 0401ca714a caused
a bus error for the vsynth3-asv[12] tests, because
the stride in these tests is unaligned. See e.g.
https://fate.ffmpeg.org/report.cgi?slot=armv7-linux-gcc-13&time=20250527020548https://fate.ffmpeg.org/report.cgi?slot=rv64gcvb-linux-gnu-gcc&time=20250527001827
It can also happen (even before said commit) if the pointers
itself are unaligned, e.g. by using the crop filter:
ffmpeg -filter_complex nullsrc=s=740x576:r=25,format=yuv420p,crop=w=720:x=2 \
-c:v asv2 -f null -
The alignment requirements for the frames passed to encoders are
mostly undocumented; the only thing I could find is the documentation
of AVFrame.linesize: "For video the linesizes should be multiples
of the CPUs alignment preference". This means that the FFmpeg cli
violates our API.
Yet as the above command line shows, it can also happen with
unaligned pointers and there does not seem to be a prohibition
of this, so we need to handle this case. This commit does so
by using get_pixels_unaligned when needed.
Reviewed-by: Martin Storsjö <martin@martin.st>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
crcref needs to be set properly iff ec is two, regardless
of whether it has been explicitly set by the user or set
by default based on level/version.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is only used to indicate to ff_h263_show_pict_info()
that we are decoding H.263+; pass this information
via a function parameter instead.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This means that these buffers won't be allocated any more
for H.263+ with AIC disabled.
Also remove setting h263_plus for the RV20 encoder,
as it has only been done to force allocating dc_val.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Just ensure that dct_unquantize_inter is set iff it is used
and check for the function pointer instead.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This allows to remove checks from ff_xvid_idct_init()
(and also the AVCodecContext* parameter).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
ff_xvid_idct_init() is now only called from ff_idctdsp_init()
and only if idct_algo is FF_IDCT_XVID.
This also implies that it is unnecessary to initalize
the permutation on our own.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is unnecessary: If the dst context is not already initialized,
then it will be initialized by memcpy(dst, src, sizeof(*dst),
which already initializes the IDCT to the desired one, potentially
followed by ff_mpv_common_init(), which does not touch the IDCT.
(This call has been added in f89d76c103;
the aforementioned copying took place back then, too, but
ff_mpv_common_init() reinitialized the IDCT to a non-xvid one,
therefore the initialization here has been added to fix
multithreaded decoding.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
These are sufficiently different to warrant their own functions;
in particular, the earlier code had two callsites for the actual
"write block" function, one for intra and one for inter, yet
the "write block" function nevertheless performed a check
(that the compiler can't optimize away) for whether the current
MB is intra or not.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
While it offers modest speedups compared to the ordinary code,
removing it completely offers even bigger speedups; and given
that these speedups also exist in the ordinary mode, they are
even more important. The no-output code has a 7.8% performance
improvement (based on benchmarking mpeg4_encode_mb()), yet
removing the no-output code resulted in a 9.4% improvement.
Furthermore, the no-output code was broken for the majority of
its existence (until 9207dc3b0d)
and no one complained, so it is likely not used at all.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The MPEG-4 decoder can now initialize ff_mpeg4_rl_intra
directly given that the MPEG-4 encoder no longer wants
it performed, too.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
There four cases for the LUT entry: An ordinary entry
or one of three escaping methods. Three of these methods
are only rarely possible --they correspond to the 102
codes of the underlying VLC and so only 102 of 16384 entries
are possible.
The earlier code would nevertheless try them all for every
LUT entry and use the best one; the new code meanwhile only
uses one method (the fallback one (i.e. the worst)) for them all
and only processes the 102 valid entries afterwards.
The implementation used also means that index_run, max_level
and max_run of the RLTable are no longer needed; the earlier
code would initialize said static tables although they are only
used for a short time to initialize something else.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Multiple PutBitContexts are used when encoding partitioned
frames. When there are multiple candidates for macroblock types,
multiple states (namely the state before encoding the current MB,
the best state among the ones already tried and the current one)
need to be kept; duplicates of the PutBitContexts are among this
state. The temporary buffers for them are kept on the stack
in encode_thread() and their size is quite generous (MAX_MB_SIZE
- 3000 bytes). This commit uses tighter bounds, bringing the
size of the pb2 buffer down to 15 bytes.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The reversible VLC tables use a simpler escaping method
than the ordinary VLCs: It does not use max_run, max_level etc.
and therefore one does not need to initialize these at all.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is confusing, because the AV_RL32("ASUS") already
returns an endian-independent value, so converting
it via av_le2ne32() makes no real sense: one would need
to transform the native value to le and write it as
a natie endian uint32_t for it to make sense (the current
code only works because le2ne32 and ne2le32 are the same
for both endianness that we care about). Or one can just
use AV_RL32 and create the number via MKTAG().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Removes implicit checks for "do I need to output the buffer now?".
Codesize with Clang 19 with -O3 decreased from 7136B to 6108B
(although asv2_put_level() is now inlined).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Up until now, the encoder replicated all the border pixels
for incomplete 16x16 macroblocks. In case the available width
or height is <= 8, some of the luma blocks of the MB
do not correspond to actual input, so that we should encode
them using the least amount of bits. Zeroing the block coefficients
(as this commit does) achieves this, replicating the pixels
and performing an FDCT does not.
This commit also removes the frame copying code for insufficiently
aligned dimensions.
The vsynth3-asv[12] FATE tests use a 34x34 input file and are
therefore affected by this. As the ref updates show, the size
and checksum of the encoded changes, yet the decoded output
stays the same.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Add three missing requirements on bitstream conformance from 7.4.3.19 of
H.266 (V3). Issue found using fuzzing.
Signed-off-by: Frank Plowman <post@frankplowman.com>
When called for palette-predicted CUs, boundary_strength could cause
undefined behaviour due to accessing uninitialised motion information.
The spec doesn't include this, but in the reference software it seems
the deblock strength is always set to 0 for palette CUs due to some
implementation details: perhaps this is a spec issue?
Signed-off-by: Frank Plowman <post@frankplowman.com>
In d5dbcc00d8, it was hoped that detection
of subpicture overlaps could be performed at the tile level, so as to
avoid introducing per-CTU checks. Unfortunately since that patch,
fuzzing has indicated there are some structures involving
pps_subpic_one_or_more_tiles_slice where tile-level checking is not
sufficient. Performing the check at the CTU level should (touch wood)
be the be-all and and-all of this, as CTUs are the lowest common
denominator of the picture partitioning.
Signed-off-by: Frank Plowman <post@frankplowman.com>
