Commit graph

596 commits

Author SHA1 Message Date
Andreas Rheinhardt
43abd1ced9 avcodec/mpegvideo: Move last_dc to {H263Dec,Mpeg12Slice,MPVEnc}Context
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-11-21 11:55:09 +01:00
Andreas Rheinhardt
dad06a445f avcodec/Makefile: Remove h263 decoder->mpeg4videodec.o dependency
Also prefer using #if CONFIG_MPEG4_DECODER checks in order not
to rely on DCE.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-10-11 07:51:01 +02:00
Andreas Rheinhardt
10d3479da0 avcodec/h263dec: Avoid redundant branch
Only the MPEG-4 decoder can have partitioned frames here.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-10-11 07:51:01 +02:00
Andreas Rheinhardt
367cf961ea avcodec/get_bits: Add get_bits_bytesize()
And use it to avoid accesses to GetBitContext.buffer_end.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-11 15:13:21 +02:00
Andreas Rheinhardt
abc54c25be avcodec/mpegvideo: Move loop_filter to {H263Dec,MPVEnc,VC1}Context
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:32 +02:00
Andreas Rheinhardt
60f51bdaac avcodec/mpegvideo: Move partitioned_frame to {H263Dec,MPVEnc}Context
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:32 +02:00
Andreas Rheinhardt
0984724d1e avcodec/mpeg_er: Allow to skip setting partitioned_frame, p[pb]_time
Instead of setting these unconditionally (they are always zero
for H.261, MPEG-1/2, RV30/40, VC-1), add a variant of
ff_mpeg_er_frame_start() that sets them and remove setting them
from ff_mpeg_er_frame_start(). Also pass these values via parameters
instead of reading them from the MPVContext itself.
This will allow to move them from MPVContext.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
3c06d87c93 avcodec/mpegvideo: Move fields to {H263Dec,MPVEnc}Context when possible
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
00ea78f426 avcodec/flvdec: Binarize h263_flv
It used to be a tri-state encoding both whether to use FLV picture
headers and whether to use the FLV way of encoding escape values,
but the former is now unnecessary due to the switch to a function
pointer for reading the header. So binarize h263_flv.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
c660f45f8e avcodec/h263dec: Use function ptr for decode_picture_header
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
7db6267b30 avcodec/mpegvideo: Move fields only used by H.263 decoders to H263DecCtx
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
8a4accc24d avcodec/h263dec: Stop using MpegEncContext.gb
Add a GetBitContext to H263DecContext instead. This is in preparation
for removing MpegEncContext.gb.
Also move last_resync_gb to H263DecContext.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
77add26918 avcodec/h263dec: Don't use MpegEncContext.block
Instead add the necessary blocks directly to H263DecContext
(only six are needed, not 12 as ff_mpv_common_init()
currently allocates).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
b2be342ab6 avcodec/h263dec: Remove redundant block parameter from decode_mb
With the exception of mpeg4_decode_studio_mb(), all decode_mb
functions implicitly presumed that the block provided as
argument coincides with MpegEncContext.block (they zeroed the latter
and then used the former to decode the block); mpeg4_decode_studio_mb()
meanwhile did not use the provided block at all (it uses blocks of
int32_t). So remove said parameter.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:31 +02:00
Andreas Rheinhardt
584d50c5f3 avcodec/h263dec: Add H263DecContext
This is in preparation for moving the fields only used
by H.263-based decoders from MPVContext to H263DecContext.
For now only the decode_mb function pointer has been moved
(to be able to switch said callback to use an H263DecContext*).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:35:23 +02:00
Andreas Rheinhardt
758c8dffc9 avcodec/{h263,mpeg4video}dec: Pass MPVContext*, not Mpeg4DecContext*
The code in h263dec.c is not supposed to know that the MPEG-4
decoder uses an Mpeg4DecContext as private context at all
(said context is only exposed in a header so that hardware
accelerations can access it and for the parser to use).
Passing an MPVContext* directly also allows to remove
the indirection via AVCodecContext.priv_data.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-07-03 20:34:51 +02:00
Andreas Rheinhardt
13527b39bb avcodec/mpegvideo: Redo resetting intra table entry
All callers check the corresponding entry of MpegEncContext.mbintra_table
and if set (indicating that the intra tables might have been written to
when decodeing a intra MB, so that they are "dirty"), call
ff_clean_intra_table_entries(), which resets them to default values
and resets the mbintra_table entry. Move resetting to the callers
(via an inline function that also performs the checks). This currently
has the advantage that the additional load of the mbintra_table ptr
can be avoided. It will also allow to simplify
ff_clean_intra_table_entries() (by using block_index[4] and [5]).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-06-21 22:08:52 +02:00
Andreas Rheinhardt
778c0a48fa avcodec/mpegvideo_dec: Simplify check for unquantizing inter blocks
Just ensure that dct_unquantize_inter is set iff it is used
and check for the function pointer instead.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-26 04:53:32 +02:00
Andreas Rheinhardt
a0a136e57b avcodec/h263dec: Move calculating gob_index to {intel,itu}h263dec.c
This avoids checks for whether it should be calculated at all.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-26 04:02:32 +02:00
Andreas Rheinhardt
0d73ce4bc4 avcodec/h263dec: Use av_unreachable() for unreachable code
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-26 03:38:37 +02:00
Andreas Rheinhardt
a1e4be5740 avcodec/mpegvideo_dec: Move ff_mpv_report_decode_progress() to h263dec.c
It is its only user. Also make it static and call it
before ff_mpeg_draw_horiz_band().

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-21 02:54:22 +02:00
Andreas Rheinhardt
2865ebd1fb avcodec/mpeg4videodec,h263dec: Only set skipped_last_frame for !vop_coded
This is more in line with the spec and avoids a branch.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-16 01:37:35 +02:00
Andreas Rheinhardt
c37fb99abb avcodec/h263dec: Always output next, not current pic when flushing
It is the last picture in display order.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-16 01:37:35 +02:00
Andreas Rheinhardt
6ce86c9c11 avcodec/mpeg4videodec: Permute quant matrices directly upon IDCT reinit
When switching to the XviD IDCT, the IDCT permutation can change.
Given that we already permute the quant matrices when parsing
them, they need to be permuted, too. Up until now this has not been
done; instead the header has been parsed again in the expectation
that the currently active quant matrix is contained in this header.

This expectation is wrong; it is for example wrong when the VOL
header is only available via extradata (such a file can be easily
created from xvid_vlc_trac7411.h263 (in the FATE suite) via the
remove_extra BSF). It could also be wrong if the XviD user data
is only available in a subsequent packet.

This commit therefore switches to permuting the relevant matrices
directly. It also stops parsing the header a second time
when switching to the XviD IDCT.

(I wonder whether ff_mpv_idct_init() should take alternate_scan
into account when initializing permutated_intra_h_scantable
as the decoder does. Does the MPEG-4 encoder use a wrong scantable
in this case?)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-05-16 01:37:35 +02:00
Andreas Rheinhardt
e5a33c898a avcodec/mpegvideo: Only keep the actually used unquantize funcs
For all encoders and all decoders except MPEG-4 the unquantize
functions to use don't change at all and therefore needn't be
kept in the context. So discard them after setting them;
for MPEG-4, the functions get assigned on a per-frame basis.

Decoders not using any unquantize functions (H.261, MPEG-1/2)
as well as decoders that only call ff_mpv_reconstruct_mb()
through error resilience (RV30/40, the VC-1 family) don't have
the remaining pointers set at all.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-26 04:17:00 +01:00
Andreas Rheinhardt
c757f948d1 avcodec/mpegvideo: Don't initialize [yc]_dc_scale_table by default
Only the H.263-based decoders as well as the encoders need it;
so move it to ff_h263_decode_init() as well as ff_mpv_encode_init().
Also for the latter make it only set these tables if none are
already set.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-26 03:09:47 +01:00
Lynne
caff29dbb1
FFHWAccel: add buffer_ref argument to start_frame
This commit adds a reference to the buffer as an argument to
start_frame, and adapts all existing code.

This allows for asynchronous hardware accelerators to skip
copying packet data by referencing it.
2025-03-17 08:51:23 +01:00
Andreas Rheinhardt
e6d07e45e0 avcodec/{h263,ituh263,msmpeg4,snow}dec: Use proper logcontext
The logging functions here can be reached by codecs without
private class, so that the log callback will receive a non-NULL
object whose AVClass pointer is NULL. Although the default log
callback handles this gracefully, it is probably an API violation.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-08 01:05:46 +01:00
Andreas Rheinhardt
4f2becc2dc avcodec/mpeg4videodec: Avoid copying packed bitstream data
This is possible because the packet is reference-counted
and because we never combine the data from several packets.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-04 12:58:30 +01:00
Andreas Rheinhardt
e3ebc1073e avcodec/mpegvideo: Move bitstream_buffer to mpeg4videodec
This is possible by moving the code using it to open a GetBitContext
from h263dec.c to mpeg4videodec.c.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-04 12:58:30 +01:00
Andreas Rheinhardt
e4470a8e30 avcodec/h263dec: Don't call ff_thread_finish_setup() unnecessarily
All hwaccels for MPEG-4/H.263 are run serially even when frame-threading
is in use. Therefore there is no gain in calling
ff_thread_finish_setup() in this case right before outputting
the frame.

Removing this call also allows to revert commit
39a5c0ac06.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-04 12:58:30 +01:00
Andreas Rheinhardt
e6657d499a avcodec/h26[134]dec: Always report the buffer to be completely consumed
It is pointless to try to report the true number because
decode_simple_internal() always treats the buffer as
completely consumed for video codecs anyway.
(Apart from that: The h263dec code would report to only
have consumed the header data in case decoding is aborted
due to skip_frame which makes no sense.)

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-03-04 12:58:30 +01:00
Andreas Rheinhardt
5826166836 avcodec/h263dec: Clean intra tables in decoder, not ff_mpv_reconstruct_mb
This is a more appropriate place than a function designed
to reconstruct a macroblock. It furthermore limits these checks
to the codecs that actually need it (and removes it from e.g.
RV10 and RV20 -- the latter actually uses these buffers, but
only for intra-frames, so they don't need to be cleaned
manually).

This furthermore means that ff_mpv_reconstruct_mb() and therefore
also the error-resilience code no longer needs block_index set.
This fixes a crash caused by 65d5ccb808
when ff_mpv_reconstruct_mb() is called by VC-1 code without
block_index being initialized properly (VC-1 uses and initializes
block_index itself normally).

Fixes: 69814/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_VC1_fuzzer-4868081575329792
Fixes: heap-buffer-overflow

Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2025-02-23 02:01:08 +01:00
Michael Niedermayer
0fe33c99a2
avcodec/h263dec: Check against previous dimensions instead of coded
Fixes: out of array access
Fixes: crash-a41ef3db699013f669b076f02f36942925f5a98c

Found-by: Kacper Michajlow <kasper93@gmail.com>
Reviewed-by: Kacper Michajlow <kasper93@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2025-01-31 23:10:03 +01:00
Andreas Rheinhardt
48cdb7d579 avcodec/mpegvideo_dec: Move setting dct_unquant funcs to h263dec.c
It is a better place for it; no non-h263-based decoder needs
these functions any more (both H.261 and the error resilience
code recently stopped doing so).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-20 18:58:39 +02:00
Andreas Rheinhardt
594723ec38 avcodec/mpegvideo: Move quant_precision to Mpeg4DecContext
It is an MPEG-4-only value; it is always five for the MPEG-4
encoder, so just hardcode this value and move the MpegEncContext
field to Mpeg4DecContext.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-20 18:58:39 +02:00
Andreas Rheinhardt
c735552b0b avcodec/rv10: Use ff_h263_decode_init()
The RV10 and RV20 decoders use ff_h263_decode_mb() and also the
H.263 DSP and VLCs. Despite not calling ff_h263_decode_frame(),
it is nevertheless beneficial to call ff_h263_decode_init()
to reduce code duplication.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-20 18:58:39 +02:00
Andreas Rheinhardt
18f1aca3e8 avcodec/mpegvideo_dec: Set dct_unquantize ptrs only once when possible
Everything except dct_unquantize_intra for MPEG-4 need only
be set once.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-20 18:58:38 +02:00
Andreas Rheinhardt
b2ac792367 avcodec/mpegvideo: Use enum for msmpeg4_version
Improves readability.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-12 12:03:00 +02:00
Andreas Rheinhardt
9ce56f91c0 avcodec/mpegpicture: Make MPVPicture refcounted
Up until now, an initialized MpegEncContext had an array of
MPVPictures (way more than were ever needed) and the MPVPicture*
contained in the MPVWorkPictures as well as the input_picture
and reordered_input_picture arrays (for the encoder) pointed
into this array. Several of the pointers could point to the
same slot and because there was no reference counting involved,
one had to check for aliasing before unreferencing.
Furthermore, given that these pointers were not ownership pointers
the pointers were often simply reset without unreferencing
the slot (happened e.g. for the RV30 and RV40 decoders) or
there were moved without resetting the src pointer (happened
for the encoders where the entries in the input_picture
and reordered_input_picture arrays were not reset).
Instead actually releasing these pictures was performed by looping
over the whole array and checking which one of the entries needed
to be kept. Given that the array had way too many slots (36),
this meant that more than 30 MPVPictures have been unnecessarily
unreferenced in every ff_mpv_frame_start(); something similar
happened for the encoder.

This commit changes this by making the MPVPictures refcounted
via the RefStruct API. The MPVPictures itself are part of a pool
so that this does not entail constant allocations; instead,
the amount of allocations actually goes down, because the
earlier code used such a large array of MPVPictures (36 entries) and
allocated an AVFrame for every one of these on every
ff_mpv_common_init(). In fact, the pool is only freed when closing
the codec, so that reinitializations don't lead to new allocations
(this avoids having to sync the pool in update_thread_context).

Making MPVPictures refcounted also has another key benefit:
It makes it possible to directly share them across threads
(when using frame-threaded decoding), eliminating ugly code
with underlying av_frame_ref()'s; sharing these pictures
can't fail any more.

The pool is allocated in ff_mpv_decode_init() for decoders,
which therefore can fail now. This and the fact that the pool
is not unreferenced in ff_mpv_common_end() also necessitated
to mark several mpegvideo-decoders with the FF_CODEC_CAP_INIT_CLEANUP
flag.

*: This also means that there is no good reason any more for
ff_mpv_common_frame_size_change() to exist.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-12 11:47:49 +02:00
Andreas Rheinhardt
99d26939af avcodec/mpegvideo_dec: Add close function for mpegvideo-decoders
Currently identical to the H.261 and H.263 close functions
(which it replaces). It will be extended in future commits.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-12 11:44:13 +02:00
Andreas Rheinhardt
fe6037fd04 avcodec/mpegpicture: Split MPVPicture into WorkPicture and ordinary Pic
There are two types of MPVPictures: Three (cur_pic, last_pic, next_pic)
that are directly part of MpegEncContext and an array of MPVPictures
that are separately allocated and are mostly accessed via pointers
(cur|last|next)_pic_ptr; they are also used to store AVFrames in the
encoder (necessary due to B-frames). As the name implies, each of the
former is directly associated with one of the _ptr pointers:
They actually share the same underlying buffers, but the ones
that are part of the context can have their data pointers offset
and their linesize doubled for field pictures.

Up until now, each of these had their own references; in particular,
there was an underlying av_frame_ref() to sync cur_pic and cur_pic_ptr
etc. This is wasteful.

This commit changes this relationship: cur_pic, last_pic and next_pic
now become MPVWorkPictures; this structure does not have an AVFrame
at all any more, but only the cached values of data and linesize.
It also contains a pointer to the corresponding MPVPicture, establishing
a more natural relationsship between the two.
This already means that creating the context-pictures from the pointers
can no longer fail.

What has not been changed is the fact that the MPVPicture* pointers
are not ownership pointers and that the MPVPictures are part of an
array of MPVPictures that is owned by a single AVCodecContext.
Doing so will be done in a latter commit.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-12 11:38:13 +02:00
Andreas Rheinhardt
ec1eba792a avcodec/mpegvideo: Shorten variable names
current_picture->cur_pic, last_picture->last_pic, similarly
for new_picture and next_picture.
Also rename the corresponding *_ptr fields.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-06-12 11:19:44 +02:00
Andreas Rheinhardt
66923165d5 avcodec/mpegutils: Move definitions to better places
FRAME_SKIPPED -> h263dec.h
CANDIDATE_MB_TYPE_* -> mpegvideoenc.h
INPLACE_OFFSET -> mpegvideoenc.h
enum OutputFormat -> mpegvideo.h

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-04-08 15:00:01 +02:00
Andreas Rheinhardt
2b0e9e278a avcodec/h263dec: Remove AVCodec.pix_fmts arrays
They are not intended for decoders (for which there is the get_format
callback in case the user has a choice).

Also note that the list was wrong for MPEG4, because it did not contain
the high bit depth pixel formats used for studio profiles.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2024-02-09 08:16:25 +01:00
Andreas Rheinhardt
ca3dea8a36 avcodec/h263dec, mpeg4videodec: Parse extradata during init
Possible now that the IDCT is already initialized at this point.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2023-10-05 22:05:21 +02:00
Andreas Rheinhardt
49b4ed7237 avcodec/mpegvideo_dec: Always initialize IDCTDSPContext during init
It has currently not been done for H263, H263P and MPEG4.
Doing so avoids having to initialize the IDCT permutation
lateron when decoding packets in order to be able to parse
a quant matrix; it means that every mpegvideo decoder always
has an initialized IDCTDSPContext after init.
Initializing is done generically in ff_mpv_decode_init().

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2023-10-05 22:05:21 +02:00
Andreas Rheinhardt
d2bc039501 avcodec/error_resilience: Make applying decode_error_flags optional
Add a pointer parameter that if supplied will be used to return
the updated decode_error_flags. This will allow to fix several
races when using frame-threading; these resulted from AVFrame
that the earlier code updated concurrently being used as source
in an av_frame_ref() call in the decoder's update_thread_context.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2023-09-15 13:08:37 +02:00
Andreas Rheinhardt
e35dfe864d avcodec/avcodec: Add FFHWAccel, hide internals of AVHWAccel
This commit is the AVHWAccel analogue of commit
20f9727018: It moves the private fields
of AVHWAccel to a new struct FFHWAccel extending AVHWAccel
in an internal header (namely hwaccel_internal.h).

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2023-08-07 09:50:29 +02:00
Michael Niedermayer
fead656a7b
avcodec: Ignoring errors is only possible before the input end
Fixes: out of array read
Fixes: Ticket 10308

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2023-06-18 14:29:11 +02:00