VLC_MULTI_ELEM contains an uint8_t array that is supposed
to be treated as an array of uint16_t when the used symbols
have a size of two; otherwise it should be treated as just
an array of uint8_t, but it was not always treated that way:
vlc_multi_gen() initialized the first entry of the array
by writing the symbol via AV_WN16; on big endian systems,
the intended value was instead written into the second entry
of the array (where it would likely be overwritten lateron
during initialization).
read_vlc_multi() also treated this case incorrectly: In case
the code is so long that it needs a classical multi-stage lookup,
the symbol has been written to the destination as if via AV_WN16.
On little endian systems, this sets the correct first symbol and
clobbers (zeroes) the next one, but the next one will be overwritten
lateron anyway, so it won't be recognized. But on big-endian systems,
the first symbol will be set to zero and the actually read symbol
will be put into the slot for the next one (where it will be overwritten
lateron).
This commit fixes this; this fixes the magicyuv and utvideo FATE-tests
on big endian arches.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Therefore use a proper prefix for this API, e.g.
ff_init_vlc_sparse -> ff_vlc_init_sparse
ff_free_vlc -> ff_vlc_free
INIT_VLC_LE -> VLC_INIT_LE
INIT_VLC_USE_NEW_STATIC -> VLC_INIT_USE_STATIC
(The ancient INIT_VLC_USE_STATIC has been removed
in 595324e143, so that
the NEW has been dropped.)
Finally, reorder the flags and change their values
accordingly.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
bits_*_signed(0) will currently invoke an undefined shift by
8 * sizeof(int).
Add bits_*_signed_nz() that only works for n>0, analogous to
bits_read_nz(). Add an explicit check for n=0 in bits_*_signed().
Found-by: James Almer
