This e.g. allows compilers to bake the offset implied
by using ff_vc1_b_field_mvpred_scales[3] into the
general offset; for certain arches this is also necessary
in order to avoid building suboptimal code.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is the only encoder supporting quarter samples.
This also allows to remove the qpeldsp dependency from
mpegvideo_enc.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The MPEG-4 decoder is the only decoder based upon H.263 that
supports quarterpel motion vectors.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The only thing from the H.263 decoder that is reachable
by the VC-1 decoder is ff_h263_decode_init(); but it does
not even use all of it; e.g. h263dsp is unused and so are
the VLCs initialized in ff_h263_decode_init() (they amount
to about 77KB which are now no longer touched).
Notice that one could also call ff_idctdsp_init()
directly instead of ff_mpv_idct_init(); one could even
do so in ff_vc1_init_common().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Decoders that might use quarter pixel motion estimation
(namely MPEG-4 as well as the VC-1 family) currently
use MpegEncContext.me.qpel_(put|avg) as scratch space
for pointers to arrays of function pointers.
(MotionEstContext contains such pointers as it supports
quarter pixel motion estimation.) The MotionEstContext
is unused apart from this for the decoding part of
mpegvideo.
Using the context at all is for decoding is actually
unnecessary and easily avoided: All codecs with
quarter pixels set me.qpel_avg to qdsp.avg_qpel_pixels_tab,
so one can just unconditionally use this in ff_mpv_reconstruct_mb().
MPEG-4 sets qpel_put to qdsp.put_qpel_pixels_tab
or to qdsp.put_no_rnd_qpel_pixels_tab based upon
whether the current frame is a b-frame with no_rounding
or not, while the VC-1-based decoders set it to
qdsp.put_qpel_pixels_tab unconditionally. Given
that no_rounding is always zero for VC-1, using
the same check for VC-1 as well as for MPEG-4 would work.
Since ff_mpv_reconstruct_mb() already has exactly
the right check (for hpeldsp), it can simply be reused.
(This change will result in ff_mpv_motion() receiving
a pointer to an array of NULL function pointers instead
of a NULL pointer for codecs without qpeldsp (like MPEG-1/2).
It doesn't matter.)
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
vc1_decode_skip_blocks() is only called if the current picture
is a P frame. So setting pict_type to AV_PICTURE_TYPE_P
is redundant; removing it makes pict_type read-only in vc1_block.c
(as it should be).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The only msmpeg4 code that is ever executed by the VC-1 based
decoders is ff_msmpeg4_decode_init() and what is directly
reachable from it. This is:
a) A call to av_image_check_size(), then ff_h263_decode_init(),
b) followed by setting [yc]_dc_scale_table and initializing
scantable/permutations.
c) Afterwards, some static tables are initialized.
d) Finally, slice_height is set.
The replacement for ff_msmpeg4_decode_init() performs a)
just like now; it also sets [yc]_dc_scale_table,
but it only initializes inter_scantable and intra_scantable
and not permutated_intra_[hv]_scantable: The latter are only
used inside decode_mb callbacks which are only called
in ff_h263_decode_frame() which is unused for VC-1.*
The static tables initialized in c) are not used at all by
VC-1 (the ones that are used have been factored out in
previous commits); this avoids touching 327KiB of .bss.
slice_height is also not used by the VC-1 decoder (setting
it in ff_msmpeg4_decode_init() is probably redundant after
b34397b4cd).
*: It follows from this that the VC-1 decoder is not really
based upon the H.263 decoder either; changing this will
be done in a future commit.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This is in preparation for splitting VC-1 from msmpeg4.
(msmpeg4data.c was originally intended to be just this;
9488b966c7 changed it).
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This is done since 16af29a7a6
(and is actually unnecessary, because the tables initialized
in ff_msmpeg4_decode_init() are only ever used in vc1_block.c
which is only entered after a call to ff_msmpeg4_decode_init())
in a very ugly manner; said manner had the byproduct of
involving lots of unnecessary allocations and even opening
and closing a hwaccel in case one is used.
This commit achieves the aim of 16af29a7a6
by initializing the VLCs used by VC-1 in ff_vc1_init_common().
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
VC1 shares some VLCs with MSMPEG-4, but vc1_block.c
simply duplicates the defines instead of including
the appropriate headers; furthermore, use a proper
prefix for these defines: DC_VLC_BITS is also used
by other codecs.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
and include said header at the place where the VLCs are created.
This allows to make said tables static.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
ff_vc1_norm6_spec has been removed in commit
356be9307c (and it seems that it
has never been used); the declarations of the 8x8_zz arrays meanwhile
have been added in f0c02e1cbc
without having ever been defined.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
The defines in vc1data.c are duplicates of the ones in vc1data.h;
they are also pointless, because they are not used anywhere.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
It is unnecessary to initialize the VLCs: The only VLC
that was only ever used by the code reachable from the parser
was ff_vc1_bfraction_vlc; and this VLC has been removed.
Yet vc1dsp is still needed for startcode_find_candidate.
Maybe this should be factored out of vc1dsp in a later
commit.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Added in b50be4e38dc83389925dc14f24fa11e660d32197;
this check was racy back then (as the VLC could be initialized
concurrently) and it is redundant (always-false)
since commit c742ab4e81.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This check has been added in c617bed34f,
merging ee769c6a7c to fix
a possible segfault if AVCodecContext.codec is not set
as it may be during parsing. While this fixes the segfault,
it has the unfortunate side effect that it makes the output
of the parser dependent on whether a decoder is set (and
ultimately available). The fix later applied in
5d2be71b9e does not have this
downside and makes checking AVCodecContext.codec superfluous.
So remove this check.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
There are sill many users of these APIs within libav*, so this commit
introduced too many deprecation warnings, making compilation too noisy and
potentially hiding legit warnings.
Once the remaining users are ported, this can be reapplied.
This reverts commit 76d0038579.
The encoder is fixed point, and uses an MDCT only for analysis. Due
to the slightly different rounding, the encoder makes a different
decision, so the tests have to be adjusted as well.
