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Commit Graph

12 Commits

Author SHA1 Message Date
Andreas Rheinhardt
9cdf82c2c2 avcodec/vlc: Use proper namespace
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>
2023-09-11 00:27:45 +02:00
Andreas Rheinhardt
e6d89d0efd avcodec/cfhddata: Reduce stack usage
Creating CFHD RL VLC tables works by first extending
the codes by the sign, followed by creating a VLC,
followed by deriving the RL VLC from this VLC (which
is then discarded). Extending the codes uses stack arrays.

The tables used to initialize the VLC are already sorted
from left-to-right in the tree. This means that the
corresponding VLC entries are generally also ascending,
but not always: Entries from subtables always follow
the corresponding main table although it is possible
for the right-most node to fit into the main table.

This suggests that one can try to use the final destination
buffer as scratch buffer for the tables with sign included.
Unfortunately it works for neither of the tables if one
uses the right-most part of the RL VLC buffer as scratch buffer;
using the left-most part of the RL VLC buffer as scratch buffer
might work if one traverses the VLC entries from end to start.
But it works only for the little RL VLC (table 9), not for table 18.

Therefore this patch uses the RL VLC buffer for table 9
as scratch buffer for creating the bigger table 18.
Afterwards the left part of the buffer for table 9 is
used as scratch buffer to create table 9.

This fixes the cfhd part of ticket #9399 (if it is not already fixed).
Notice that I do not consider the previous stack usage excessive.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-05 14:28:20 +02:00
Andreas Rheinhardt
9e9c99366a avcodec/cfhd, cfhddata: Free VLC as soon as it is not needed
The VLC is only used to initialize RL VLC.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-05 14:28:13 +02:00
Andreas Rheinhardt
320c36d9c7 avcodec/cfhddata: Avoid code duplication when creating codebooks
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-05 14:28:06 +02:00
Andreas Rheinhardt
764cacfdb6 avcodec/cfhddata: Avoid code tables
cfhddata.c initializes a RL VLC table via code tables and
corresponding tables for length, run and level. code and length
tables are used to initialize a VLC, no symbol table is used.
Afterwards the symbols of said VLC are just the indices of
the corresponding entries in the code and length table that
were used for initialization; they can therefore be used
to get the matching level and run entry and they are not used
for anything else. Therefore one can just permute these tables
without changing the resulting RL VLC tables.

This commit does just this. It permutes these tables so that
the code tables are ordered from left to right in the resulting
tree and then switches to ff_init_vlc_from_lengths(), which
allows to remove the codes table altogether.

Given that these tables are constructed on the stack, this
also reduces stack usage, potentially fixing part of #9399.
(The size of the tables on the stack decreases from 4752 to
2640.)

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-05 14:27:58 +02:00
Andreas Rheinhardt
6b1a7fc8bd avcodec/cfhd, cfhddata: Simplify check for escape
cfhd.c checked for level being equal to a certain codebook-
dependent constant and to run being two. The first check is
actually redundant, as all codebooks contain only one (real)
entry with run == 2 (as is usual with VLCs, this one real entry
has several corresponding entries in the table). But given
that no entry has a run of zero (except incomplete entries
which just signal that one needs to do another round of parsing),
one can actually use that as sentinel. This patch does so.

Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-09-05 14:22:30 +02:00
Paul B Mahol
4beac58e90 avcodec/cfhd: fix escape handling for old codebook 2022-09-03 14:44:58 +02:00
Paul B Mahol
10ed73e933 avcodec/cfhddata: remove unused defines 2022-09-03 14:44:58 +02:00
Andreas Rheinhardt
2d764069be avcodec/vlc: Use structure instead of VLC_TYPE array as VLC element
In C, qualifiers for arrays are broken:
const VLC_TYPE (*foo)[2] is a pointer to an array of two const VLC_TYPE
elements and unfortunately this is not compatible with a pointer
to a const array of two VLC_TYPE, because the latter does not exist
as array types are never qualified (the qualifier applies to the base
type instead). This is the reason why get_vlc2() doesn't accept
a const VLC table despite not modifying the table at all, as
there is no automatic conversion from VLC_TYPE (*)[2] to
const VLC_TYPE (*)[2].

Fix this by using a structure VLCElem for the VLC table.
This also has the advantage of making it clear which
element is which.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-06-17 16:47:29 +02:00
James Almer
6007f7d466 Merge commit '5f794aa1653aa04c1da7397e9ccacad947fadf5f'
* commit '5f794aa1653aa04c1da7397e9ccacad947fadf5f':
  Add Cineform HD Decoder

See 3485332bf9.

Some cosmetics are merged. The refactoring is not merged at the
request of Kieran Kunhya.

Merged-by: James Almer <jamrial@gmail.com>
2017-10-17 20:28:59 -03:00
Kieran Kunhya
5f794aa165 Add Cineform HD Decoder
Decodes YUV 4:2:2 10-bit and RGB 12-bit files.
Older files with more subbands, skips, Bayer, alpha not supported.

Further fixes and refactorings by Anton Khirnov <anton@khirnov.net>,
Diego Biurrun <diego@biurrun.de>, Vittorio Giovara <vittorio.giovara@gmail.com>

Signed-off-by: Diego Biurrun <diego@biurrun.de>
2017-03-09 18:37:29 +01:00
Kieran Kunhya
3485332bf9 avcodec: Cineform HD Decoder
Decodes YUV 4:2:2 10-bit and RGB 12-bit files.
Older files with more subbands, skips, Bayer, alpha not supported.
Alpha requires addition of GBRAP12 pixel format.
2016-01-30 17:44:13 +00:00