ref_list is constructed from other fields per slice when needed, so do
not copy it for both frame and slice threading.
default_ref_list is constructed per frame and still needs to be copied
to per-slice contexts for slice threading, but a copy is not needed for
frame threading.
Clobbering these tables will temporarily clobber the template used
as a basis for other threads to start decoding from. If the other
decoding thread updates from the template right at that moment,
subsequent threads will get invalid (or, usually, none at all) mmco
tables. This leads to invalid reference lists and subsequent decode
failures.
Therefore, instead, decode the mmco tables only for the first slice in
a field or frame. For other slices, decode the bits and ensure they
are identical to the mmco tables in the first slice, but don't ever
clobber the context state. This prevents other threads from using a
clobbered/invalid template as starting point for decoding, and thus
fixes decoding in these cases.
This fixes occasional (~1%) failures of h264-conformance-mr1_bt_a with
frame-multithreading enabled.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Clobbering these tables will temporarily clobber the template used
as a basis for other threads to start decoding from. If the other
decoding thread updates from the template right at that moment,
subsequent threads will get invalid (or, usually, none at all) mmco
tables. This leads to invalid reference lists and subsequent decode
failures.
Therefore, instead, decode the mmco tables only for the first slice in
a field or frame. For other slices, decode the bits and ensure they
are identical to the mmco tables in the first slice, but don't ever
clobber the context state. This prevents other threads from using a
clobbered/invalid template as starting point for decoding, and thus
fixes decoding in these cases.
This fixes occasional (~1%) failures of h264-conformance-mr1_bt_a with
frame-multithreading enabled.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
It is not posible to call get_buffer during frame-mt codec
initialization. Libavformat might pass huge amounts of data as
extradata after parsing broken files. The 'extradata' for the fuzzed
sample sample_varPAR_s5374_r001-02.avi is 2.8M large and contains
multiple slices.
This requires to move the avcodec_default_free_buffers() call to
ff_MPV_common_end() since otherwise delayed pictures would get freed
during a size change.
This fixes out of global array reads.
The alternative solutions of checking the index or modifying the VLC tables
to prevent the index going outside are each about 1-2 cpu cyclces slower
per coded 4x4 block.
The alternative of padding the global tables directly is more ugly and
moving them to the context should benefit cache locality.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Conversion of the luma intra prediction mode to one of the constrained
("alzheimer") ones can happen by crafting special bitstreams, causing
a crash because we'll call a NULL function pointer for 16x16 block intra
prediction, since constrained intra prediction functions are only
implemented for chroma (8x8 blocks).
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Start code emulation prevention is only required in Annex B bytestream
packed NAL units. For other coding formats the size is already known.
Looking for a start code prefix can result in false positives like in
http://streams.videolan.org/streams/mp4/Mr_MrsSmith-h264_aac.mp4
which has a false positive in the SPS.
Fixes the following conformance suite samples:
HCBP1_HHI_A.264, HCBP2_HHI_A.264, HCMP1_HHI_A.264 (main)
HCHP1_HHI_B.264, HCHP2_HHI_A.264, HCHP3_HHI_A.264 (frext)
recovery points that have non-zero recovery_frame_cnt resulted in
flagging incomplete frames as keyframes. This delays setting the
keyframe flag till the frame has been fully constructed.
Fixes Ticket472
This may (or may not) cause problems with files that have no keyframes.
Plese open a bugreport or mail me if you have a file for which this fails.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Fixes the following compile error with darwin/gcc-4.2.1:
In file included from libavcodec/error_resilience.c:33:
libavcodec/h264.h: In function ‘decode_mb_skip’:
libavcodec/h264.h:773: error: ‘always_inline’ function could not be inlined in call to ‘pred_pskip_motion’: the function body must appear before caller
libavcodec/h264.h:1334: error: called from here
FF_COMMON_FRAME holds the contents of the AVFrame structure and is also copied
to struct Picture. Replace by an embedded AVFrame structure in struct Picture.
Anton Khirnov
Ronald S. Bultje
Michael Niedermayer
Janne Grunau
Marton Balint
Lou Logan
Diego Biurrun
Luca Barbato
Baptiste Coudurier
Laurent Aimar
John Stebbins
Jason Garrett-Glaser