Given that the AVCodec.next pointer has now been removed, most of the
AVCodecs are not modified at all any more and can therefore be made
const (as this patch does); the only exceptions are the very few codecs
for external libraries that have a init_static_data callback.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
Before 998c9f15d1, initializing an
MpegEncContext's IDCT parts occured in ff_mpv_common_init() and this
has been called in h261_decode_frame(), not h261_decode_init().
Yet said commit factored this out of ff_mpv_common_init() and therefore
there is no reason any more not to set this during init as this commit
does.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
This mostly reverts commit 4b2863ff01.
Said commit removed the freeing code from ff_mpv_common_init(),
ff_mpv_common_frame_size_change() and ff_mpeg_framesize_alloc() and
instead added the FF_CODEC_CAP_INIT_CLEANUP to several codecs that use
ff_mpv_common_init(). This introduced several bugs:
a) Several decoders using ff_mpv_common_init() in their init function were
forgotten: This affected FLV, Intel H.263, RealVideo 3.0 and V4.0 as well as
VC-1/WMV3.
b) ff_mpv_common_init() is not only called from the init function of
codecs, it is also called from AVCodec.decode functions. If an error
happens after an allocation has succeeded, it can lead to memleaks;
furthermore, it is now possible for the MpegEncContext to be marked as
initialized even when ff_mpv_common_init() returns an error and this can
lead to segfaults because decoders that call ff_mpv_common_init() when
decoding a frame can mistakenly think that the MpegEncContext has been
properly initialized. This can e.g. happen with H.261 or MPEG-4.
c) Removing code for freeing from ff_mpeg_framesize_alloc() (which can't
be called from any init function) can lead to segfaults because the
check for whether it needs to allocate consists of checking whether the
first of the buffers allocated there has been allocated. This part has
already been fixed in 76cea1d2ce.
d) ff_mpv_common_frame_size_change() can also not be reached from any
AVCodec.init function; yet the changes can e.g. lead to segfaults with
decoders using ff_h263_decode_frame() upon allocation failure, because
the MpegEncContext will upon return be flagged as both initialized and
not in need of reinitialization (granted, the fact that
ff_h263_decode_frame() clears context_reinit before the context has been
reinited is a bug in itself). With the earlier version, the context
would be cleaned upon failure and it would be attempted to initialize
the context again in the next call to ff_h263_decode_frame().
While a) could be fixed by adding the missing FF_CODEC_CAP_INIT_CLEANUP,
keeping the current approach would entail adding cleanup code to several
other places because of b). Therefore ff_mpv_common_init() is again made
to clean up after itself; the changes to the wmv2 decoder and the SVQ1
encoder have not been reverted: The former fixed a memleak, the latter
allowed to remove cleanup code.
Fixes: double free
Fixes: ff_free_picture_tables.mp4
Fixes: ff_mpeg_update_thread_context.mp4
Fixes: decode_colskip.mp4
Fixes: memset.mp4
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The H.261 decoder doesn't use the ParseContext of its
MpegEncContext since e731697665.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The VLC for the macroblock address increment uses nine bits;
yet there is no code with this length: All codes are either shorter or
longer. So one can make the table smaller without changing the amount of
codes that need more than one round of parsing.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The H.261 decoder only uses an RLTable's VLC table, yet it also
initializes its index_run, max_level and max_run. This commit stops
doing so; it will also simplify making this decoder init-threadsafe,
as the H.261 decoder and encoder now initialize disjoint parts of their
common RLTable.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
The H.261 decoder uses only the very first VLC of ff_h261_rl_tcoeff,
so only initialize this one. Saves 68448B from the .bss segment; in case
the decoder is actually used, this amount of memory is saved.
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
These two are always called directly after each other (with the
exception of the calls in mpeg_decode_init() where some irrelevant
modifications of the avctx (which could just as well be done before
ff_mpv_decode_defaults(), because it doesn't have a pointer to the
AVCodecContext at all and therefore can't see these modifications at
all) are performed in between), so merge ff_mpv_decode_defaults() in
ff_mpv_decode_init().
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
ff_mpv_common_init sets s->context_initialized.
This fixes decoding of h261 in the cases where the demuxer
hasn't already set the frame size.
CC: libav-stable@libav.org
Signed-off-by: Martin Storsjö <martin@martin.st>
When decoding, this field holds the inverse of the framerate that can be
written in the headers for some codecs. Using a field called 'time_base'
for this is very misleading, as there are no timestamps associated with
it. Furthermore, this field is used for a very different purpose during
encoding.
Add a new field, called 'framerate', to replace the use of time_base for
decoding.
The most interesting parts are initialization in ff_MPV_common_init() and
uninitialization in ff_MPV_common_end().
ff_mpeg_unref_picture and ff_thread_release_buffer have additional NULL
checks for Picture.f, because these functions can be called on
uninitialized or partially initialized Pictures.
NULL pointer checks are added to ff_thread_release_buffer() stub function.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
This code was originally added in
5f1948111a to h263 to set decoded frame
pts to some random numbers (removed in
a1c5cc429d) and then cargo culted to other
decoders.
The code is left in h263dec for now, since some part of the decoder
(apparently OBMC) relies on the specific previous frame to be reused.