Using a frame count, as is done currently, does not work at all with
seeking. Instead, when the number of samples in the final frame has
been decoded, we check if only the 32-bit CRC is remaining. If so, we
assume that it is the final frame.
There is no longer a need to keep total_frames in TTAContext.
Sometimes the extradata has duplicate atoms, but that shouldn't prevent
decoding. Just ensure that it is at least 36 bytes as a sanity check.
CC: libav-stable@libav.org
This is built on the assumption that the first partition of each
VP8 packet is essential for decoding any later packet - if this
partition is broken/missed, the arithmetic coder gets out of sync
and decoding the bitstream in further packet ends up with total
garbage. If packets of a frame are lost, make sure the first
partition is intact (return only this part of the packet, nothing
else), otherwise stop returning data until the next keyframe is
received.
Alternatively, one would simply not return any packets at all
until the next keyframe, if packet loss is detected.
Signed-off-by: Martin Storsjö <martin@martin.st>
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>
This makes all users of rtpenc_chain (rtsp muxer, sapenc, mov
rtp hinting) work again, broken since 8034130e0.
Signed-off-by: Martin Storsjö <martin@martin.st>
The FLV muxer tries to update the header in write_trailer, which is
impossible if writing to a pipe or network stream. Don't write header
data if seeking to the header fails.
Signed-off-by: Martin Storsjö <martin@martin.st>
The sample in https://bugzilla.libav.org/show_bug.cgi?id=393 and
samples/F4V/H263_NM_f.mp4 both have codec_tag H263 for different
codecs. H263 is apparently used by Flash Media Server for Sorensen
Spark videos.
Patch based on commit 5442083b1c by
Carl Eugen Hoyos. Fixes bug 393.
The VC1 decoder uses edge_emu_buffer simultaneously for luma and chroma
and needs more space. That was not a problem before f1d8763a02
since the size for edge_emu_buffer was always calculated with 2 byte per
pixel since the linesize was not known.
Fixes occasionally fate errors in vc1_sa10143.
It splits the commandline into a more convenient internal representation
for further parsing.
This will allow e.g.
- processing global options first independently of their location on the
commandline, eliminating ugly hacks for processing e.g. cpuflags
first
- better options validation and error reporting. It is now possible for
the parser to know that it's applying an input option to an output
file or vice versa and act accordingly.
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.
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.
It adds unnecessary complication for insignificant usability improvement.
The user really should know if they'll need resampling compensation before
opening the context.
Note that only the documentation has changed. The current functionality will
still work until the next major bump.
