Expressions like array[get_vlc2()] can be optimized by using a symbols
table if the array is always the same for a given VLC. This requirement
is fulfilled for several VLCs used by ATRAC3, therefore this commit
implements this. This comes without any additional costs when using
ff_init_vlc_from_lengths() as one can then remove the codes tables.
While at it, remove the arrays of pointers to the individual arrays and
put all lengths+symbol pairs in one big array.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The longest code of any of the VLC tables used is eight bits long, so
using nine bits long VLC tables is wasteful. Furthermore, there are only
seven VLC tables used, yet the code up until now made it look like there
should be eight. This has been corrected, too.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Do this by only keeping the only function pointer from
the AVFloatDSPContext that is needed lateron.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The largest documented frame size = block align is 1024 bytes
(https://wiki.multimedia.cx/index.php/ATRAC3)
Without a limit this can allocate arbitrary memory and trigger OOM
Fixes: OOM
Fixes: 18337/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC3_fuzzer-5763861478637568
Fixes: 18556/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC3AL_fuzzer-5646183334936576
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: Infinite loop
Fixes: 17620/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC3_fuzzer-5086123012915200
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>
Multichannel joint stereo simply interleaves stereo pairs (6ch: 2ch + 2ch + 2ch), so each pair is decoded separatedly.
***
To test my changes, I converted examples to wav with ffmpeg.exe (old and new), and compared them to see they are byte-exact.
Regular 2ch files (JS and normal) were straightforward to test.
For multichannel, to check each JS pair is correctly decoded separatedly I did:
- manually demux 6ch.msf into 3 pairs and convert them (2ch_1.wav + 2ch_2.wav + 2ch_3.wav)
- convert the 6ch.msf file to wav (with my changes)
- manually demux the 6ch.wav into 3 pairs (6ch_d1.wav + 6ch_d2.wav + 6ch_d3.wav)
- compare each pair (ex. 2ch_3.wav vs 6ch_d3.wav): all pairs are byte-exact.
The new code just processes each JS pair separatedly, there are no algorithm changes.
It could be improved a bit but I'm not sure about typical styles.
I've only seen 6ch .MSF (probably the AT3 spec only supports 2ch audio).
Signed-off-by: bnnm <bananaman255@gmail.com>
Raises max channels to 6 (for non joint-stereo only),
there is no difference decoding 1 or N discrete channels.
Fixes trac issue #5840
Signed-off-by: bnnm <bananaman255@gmail.com>
When `off' is 0, `0x537F6103 << 32' in the following expression invokes
undefined behavior, the result of which is not necessarily 0.
(0x537F6103 >> (off * 8)) | (0x537F6103 << (32 - (off * 8)))
Avoid oversized shifting.
CC: libav-stable@libav.org
Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Anton Khirnov
Andreas Rheinhardt
Paul B Mahol
Michael Niedermayer
Luca Barbato
Carl Eugen Hoyos
Diego Biurrun
bnnm
Alexandra Hájková
Vittorio Giovara
Michael Niedermayer
Gabriel Dume
Maxim Poliakovski
Xi Wang
Clément Bœsch
Justin Ruggles