Since we only know whether a NAL unit corresponds to a new field after
parsing the slice header, this requires reorganizing the calls to slice
parsing, per-slice/field/frame init and actual decoding.
In the previous code, the function for slice header decoding also
immediately started a new field/frame as necessary, so any slices
already queued for decoding would no longer be decodable.
After this patch, we first parse the slice header, and if we determine
that a new field needs to be started we decode all the queued slices.
This function's purpose is not very well defined. Currently it does two
(only marginally related) things: selecting the next output frame and
calling ff_thread_finish_setup() for frame threading. The first of those
more properly belongs under field_start(), while the second can be
called directly from decode_nal_units().
Fixes a regression in ca2f19b9cc with some mov/mp4 files. The files have
several NAL units in the supposed single NAL unit after the size field.
Annex B start code prefixes are used to separate them. The first NAL unit
is correctly parsed but the buffer does not point to the next size field.
Instead semi random data (it seems to be the rbsp_stop_one_bit and the
start code prefix) is then parsed as length and will exceed the
remaining length of the buffer.
Patch based on the code in h264's decode_nal_units() and a similar
patch by Hendrik Leppkes in FFmpeg (a9bb4cf87d).
Bug-Id: ffmpeg/trac5529
Reported-By: Vittorio Giovara
Currently, SPS.mb_height is actually what the spec calls
PicHeightInMapUnits, which is half the frame height when interlacing is
allowed. Calling this 'mb_height' is quite confusing, and there are at
least two associated bugs where this field is treated as the actual
frame height - in the h264 parser and in the code computing maximum
reordering buffer size for a given level.
Fix those issues (and avoid possible future ones) by exporting the real
frame height in this field.
This comment isn't true, the height can be different from the width
for these functions (which is why the height is passed as a parameter
to them).
Signed-off-by: Martin Storsjö <martin@martin.st>
GNU as evaluates true as '-1' while Apple's variant and llvm's internal
assembler evaluate it as '1'. The best way to avoid this madness is to
eliminate boolean expressions instead of trying to fix it with
preprocessor directives. Use a direct formula to calculate the
required temporary space on the stack in
ff_put_vp8_{epel,bilin}{4,8,16}_h[246]v[246]_armv6().
Fixes a checkasm segfault in vp8dsp.mc when using llvm's internal
assembler for a non-Apple target.
While it is less featureful (and slower) than the built-in H264
decoder, one could potentially want to use it to take advantage
of the cisco patent license offer.
Signed-off-by: Martin Storsjö <martin@martin.st>
Previously we would allocate a new one for every frame. This instead
maintains an AVBufferPool of them to use as-needed.
Also makes the maximum size of an output buffer adapt to the frame
size - the fixed upper bound was a bit too easy to hit when encoding
large pictures at high quality.
The encode function is supposed to just return 0 on success.
This stems from a mixup with the return value of decode functions.
Signed-off-by: Martin Storsjö <martin@martin.st>
Currently it's exported as AVFrame.pkt_pts, which is also the only use
for that field. The reason it is done like this is that lavc used to
export various codec-specific "timing" information in AVFrame.pts, which
is not done anymore.
Since it is confusing to the callers to have a separate field which is
used only for decoder timestamps and nothing else, deprecate pkt_pts and
use just AVFrame.pts everywhere.
Anton Khirnov
Martin Storsjö
Vittorio Giovara
Janne Grunau
Steve Lhomme
Mark Thompson
Diego Biurrun
Luca Barbato
Clément Bœsch