The decoders in this set either have a fixed channel count, or read it
from the bitstream, and thus do not require the channel count as
external information.
Fixes various regressions since
81503ac58a, which requires a valid channel
count for decoders which do not set this capability.
Signed-off-by: Hendrik Leppkes <h.leppkes@gmail.com>
Also remove code duplication and use a named constant for the number of
VLC bits while just at it.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The ATRAC9 decoder creates VLCs with parameters contained in
HuffmanCodebooks; some of these HuffmanCodebooks are empty and yet
VLCs (that were completely unused*) were created from them. Said VLC
contained a single table with 512 VLC_TYPE[2] entries, each of which
indicated that this is an invalid code. This commit stops creating said
VLCs.
*: read_coeffs_coarse() uses the HuffmanCodebook
at9_huffman_coeffs[cb][prec][cbi]. prec is c->precision_coarse[i] + 1
and every precision_coarse entry is in the 1..15 range after
calc_precision(), so prec is >= 2 (all codebooks with prec < 2 are
empty). The remaining empty codebooks are those with cb == 1 and cbi ==
0, yet this is impossible, too: cb is given by c->codebookset[i] and
this is always 0 if i < 8 (because those are never set to anything else
in calc_codebook_idx()) and cbi is given by at9_q_unit_to_codebookidx[i]
which is never zero if i >= 8.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Using separate tables has the downside that one needs a big number of
pointers to the separate tables (currently 77); unifying them avoids
this.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The ATRAC9 decoder uses VLCs which are currently initialized with
static length tables of type uint8_t and code tables of type uint16_t.
Furthermore, in one case the actually desired symbols are in the range
-16..15 and in order to achieve this an ad-hoc symbols table of type
int16_t is calculated.
This commit modifies this process by replacing the codes tables by
symbols tables and switching to ff_init_vlc_from_lengths(); the signed
symbols are stored in the table after having been shifted by 16 to fit
into an uint8_t and are shifted back when the VLC is created. This makes
all symbols fit into an uint8_t, saving space. Furthermore, the earlier
tables had holes in them (entries with length zero that were inserted
because the actually used symbols were not contiguous); these holes are
unnecessary in the new approach, leading to further saving.
Finally, given that now both lengths as well as symbols are of the same
type, they can be combined; this saves a pointer for each VLC.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The whole point of VLCs with their tables is to read more than one bit
at a time; therefore max_depth, the number of times one has to
(maximally) read further bits is given by ceil(max_code_length / table_bits)
which in the case of ATRAC9's coefficient VLCs gives an upper bound of
two. Instead the maximum length of a code of the given VLC has been used
(which is not even a compile-time constant). Use two instead.
Furthermore, given that this was the only usage of the field containing
the maximum of all the code lengths of a given VLC the field has been
removed from its containing struct.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Fixes: out of array read
Fixes: 19327/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC9_fuzzer-5679823087468544
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: index 8 out of bounds for type 'const uint8_t [8][3]'
Fixes: 19127/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC9_fuzzer-5709394985091072
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Clipping is done as it was preferred in review
See: [FFmpeg-devel] [PATCH 1/5] avcodec/atrac9dec: Check precision_fine/coarse
Fixes: out of array access
Fixes: 18330/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC9_fuzzer-5641113058148352
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Alternatively the array could be made bigger but the extra values
would not be read without other changes.
Fixes: Out of array access
Fixes: 15658/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_ATRAC9_fuzzer-5738260074070016
Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg
Reviewed-by: Lynne <dev@lynne.ee>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This commit uses smaller types for some static const arrays to reduce
their size in case the entries can be represented in the smaller type.
The biggest savings came from inv_map_table in vp9.c.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
Just remove some dead variable assignments, unneeded variables and
change the FFMAX order to something more readable. Still identical.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Much simpler than regular decoding, does allow for 5.1 and 7.1
streams to be decoded without desync.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Unlike the range, the gradient start value does not have to be lower
than the end value.
Does allow more files to be correctly decoded without errors.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
This commit implements a full ATRAC9 decoder, a simple low-delay codec
developed by Sony and used in most PSVita games, some PS3 games and some
PS4 games. Its similar to AAC in that it uses Huffman coded scalefactors
but instead of vector quantization it just Huffman codes the spectral
coefficients (in a way similar to how Opus splits band energy coding
into coarse and fine precision). It opts to write rather large Huffman
codes by packing several small coefficients into one Huffman coded
symbol, though I don't believe this increases efficiency at all.
Band extension implements SBC in a simple way, first it mirrors the
lower spectrum onto the higher frequencies and then it uses one of 5
filters to shape it. Noise substitution is implemented via 2 of them.
Unlike previous ATRAC codecs, there's no QMF, this is a standard MDCT
codec.
Based off of the reverse engineering work of Alex Barney.
Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
Anton Khirnov
Hendrik Leppkes
Andreas Rheinhardt
Michael Niedermayer
Rostislav Pehlivanov