Move some functions from dsputil. The idea is that videodsp contains
functions that are useful for a large and varied set of video decoders.
Currently, it contains emulated_edge_mc() and prefetch().
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
Since we can't know which stride a custom get_buffer() implementation is
going to use we have to allocate this scratch buffers after the linesize
is known. It was pretty safe for 8 bit per pixel pixel formats since we
always allocated memory for up to 16 bits per pixel. It broke hoever
with cmdutis.c's alloc_buffer() and high pixel bit depth since it
allocated larger edges than mpegvideo expected.
Fixes fuzzed sample nasa-8s2.ts_s244342.
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.
Adds a flag context_reinit to MpegEncContext to relieable keep track
of frame parameter changes which require a context reinitialization.
This is required for broken inputs which change the frame size but
error out before the context can be reinitialized.
This is mainly required for frame parameter changes during frame based
multithreading but single threaded usage profits too from avoiding
ff_MPV_common_end()/ff_MPV_common_init() cycles.
This file defines a single, huge function, MPV_motion(), which
although being declared inline is not actually inlined by the
compiler (for good reason). There is thus no sense in defining
this function in a header file, resulting in multiple copies of
it in the final library.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Interlaced images can have 32 references (16 per field), so limiting the
array size to 16 leads to invalid writes.
Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org
Adds a new member to MpegEncContext to hold the number of used slice
contexts. Fixes segfaults with '-threads 17 -thread_type slice' and
fate-vsynth{1,2}-mpeg{2,4}thread{,_ilace} with --disable-pthreads.
This was intended as an optimisation for skipped blocks in MPEG2
P-frames and never used elsewhere. Removing this "optimisation"
speeds up MPEG2 decoding by 1-2% (ARM Cortex-A9).
Signed-off-by: Mans Rullgard <mans@mansr.com>
This reverts commit da22ba7df4 since it
broke slice threading. Slice threading just duplicates MpegEncContext
so every value used during mpeg_decode_slice has to be in it.
A second patch will fix the illusion that Mpeg1Context is available
in mpeg_decode_slice.
The way this value is used, it should be an unsigned type.
While the numerical value has no meaning, unsigned wraparound
is relied upon.
Signed-off-by: Mans Rullgard <mans@mansr.com>
