The framework will allocate a buffer and copy the data to it,
that takes time. But it avoids constently creating and
destroyng the shared memory segment, and that saves more time.
On my setup,
from ~200 to ~300 FPS at full screen (1920×1200),
from ~1400 to ~3300 at smaller size (640×480),
similar to legacy x11grab and confirmed by others.
Plus, shared memory segments are a scarce resource,
allocating potentially many is a bad idea.
Note: if the application were to drop all references to the
buffer before the next call to av_read_frame(), then passing
the shared memory segment as a refcounted buffer would be
even more efficient, but it is hard to guarantee, and it does
not happen with the ffmpeg command-line tool. Using a small
number of preallocated buffers and resorting to a copy when
the pool is exhausted would be a solution to get the better
of both worlds.
According to spec ISO_IEC_15444_12 "For any media stream for which no segment index is present, referred to as non‐indexed stream, the media stream associated with the first Segment Index box in the segment serves as a reference stream in a sense that it also describes the subsegments for any non‐indexed media stream."
Signed-off-by: Sasi Inguva <isasi@google.com>
Reviewed-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Avoids a forward-declaration in the following commit.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
This was broken by the following Libav commit:
4c387c7 ppc: dsputil: do unaligned block accesses correctly
The following tests fail due to this:
fate-checkasm
fate-vsynth1-dnxhd-2k-hr-hq fate-vsynth1-dnxhd-edge1-hr
fate-vsynth1-dnxhd-edge2-hr fate-vsynth1-dnxhd-edge3-hr
fate-vsynth1-dnxhd-hr-sq-mov fate-vsynth1-dnxhd-hr-hq-mov
fate-vsynth2-dnxhd-2k-hr-hq fate-vsynth2-dnxhd-edge1-hr
fate-vsynth2-dnxhd-edge2-hr fate-vsynth2-dnxhd-edge3-hr
fate-vsynth2-dnxhd-hr-sq-mov fate-vsynth2-dnxhd-hr-hq-mov
fate-vsynth3-dnxhd-2k-hr-hq fate-vsynth3-dnxhd-edge1-hr
fate-vsynth3-dnxhd-edge2-hr fate-vsynth3-dnxhd-edge3-hr
fate-vsynth3-dnxhd-hr-sq-mov fate-vsynth3-dnxhd-hr-hq-mov
Fixes trac ticket #5508.
Reviewed-by: Carl Eugen Hoyos <ceffmpeg@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
The parser depends on the codec and thus must not be used with a different one.
If it is, the 'avctx->codec_id == s->parser->codec_ids[0] ...' assert in
av_parser_parse2 gets triggered.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
The old code had to retain a partial frame across two calls in
the case of separate interlaced fields. Now, we know that we'll
get both fields within the same receive_frame call, and so we
don't need to manage the frame as private state any more.
It's not possible to return EAGAIN when we've passed input EOF and are
in draining mode. If do return EAGAIN, we're saying there's no way to
get any more output - which isn't true in many cases.
So let's handled these cases in an internal loop as best we can.
It seems that without all the other 1:1 heuristics, we don't have
a fundamental problem trusting the interlaced flag on output
pictures. That's a relief.
I'm not sure why, but the mpeg4_unpack_bframes bsf is not
interacting well with seeking. Looking at the code, it should be
ok, with possibly one warning shown, but I see it getting stuck
for an extended period of time after a seek where a packed frame
is cached to be shown later.
So, I gave up on that and went back to making the old hardware
based path work. Turns out that it wasn't broken except that some
samples have a 6 byte drop packet which I wasn't accounting for.
Now it works again and seeks are good.
The new decode API allows for m:n decode patterns, which is what
you need to use this hardware in a sane way. There are so many
situations where 1:1 doesn't happen naturally that it's a miracle
I got it working as well as I did.
With this change, we can throw all of the crazy heuristics and
sleeps(!) out, and things work correctly.
Why on earth the hardware returns garbage for the first sample of
a decoded picture is anyone's guess. The simplest reasonable way
to patch it up is to copy the first sample of the second line. This
should result in the correct chroma values (because the data was
original 4:2:0 upsampled to 4:2:2) even if the luma is isn't.
This avoids potential rounding errors and guarantees the source aspect
ratio is preserved.
Keep writing pixel values when Stereo 3D Mode is enabled and for WebM,
as the format doesn't support anything else.
This fixes ticket #5743, implementing the suggestion from ticket #5903.
Signed-off-by: James Almer <jamrial@gmail.com>
This avoids continuity check failures in concatenated streams
Reviewed-by: Steven Liu <lingjiujianke@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes: out of array read
Fixes: poc.dat
Found-by: Bingchang, Liu @VARAS of IIE
Tested-by: bc L <l.bing.chang.bc@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Fixes the following warning:
libavcodec/hapenc.c:122:20: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 4 has type ‘size_t’ [-Wformat]
Based on a patch by Diego Biurrun.
Fixes remuxing apng streams coming from the apng demuxer.
This is a regression since 940b8908b9.
Found-by: James Almer <jamrial@gmail.com>
Reviewed-by: James Almer <jamrial@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
If there are no index entries, e_old = st->index_entries is only one
byte large, since it was created by av_realloc called with size 0.
Thus accessing e_old[0].timestamp causes a heap buffer overflow.
Reviewed-by: Sasi Inguva <isasi@google.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
This fixes out-of-bounds reads by the bitstream reader.
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Andreas Cadhalpun <Andreas.Cadhalpun@googlemail.com>
Merged as-at libav 398f015, and therefore includes outstanding
skipped merges 04b17ff and 130e1f1.
All features not in libav are preserved, and no options change.
Nicolas George
Sasi Inguva
Vittorio Giovara
Hendrik Leppkes
Andreas Cadhalpun
Philip Langdale
James Almer
Michael Niedermayer
Rodger Combs
Carl Eugen Hoyos
rogerdpack
Adriano Pallavicino
Martin Vignali
Kyle Schwarz
Mark Thompson