Make the SPS/PPS parsing independent of the H264Context, to allow
decoupling the parser from the decoder. The change is modelled after the
one done earlier for HEVC.
Move the dequant buffers to the PPS to avoid complex checks whether they
changed and an expensive copy for frame threads.
Instead of handling the problem inside NAL decoding code, add a higher
level wrapper function. This should be more robust against future
changes (and easier to read).
Fall back to maximum DPB size if the level is unknown.
This should be more spec-compliant and does not depend on the caller
setting has_b_frames before opening the decoder.
The old behaviour, when the delay is supplied by the caller setting
has_b_frames, can still be obtained by setting strict_std_compliance
below normal.
This makes the h.264 decoder threadsafe to initialize.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
There is not much reason to generate such a small table at runtime.
Signed-off-by: Derek Buitenhuis <derekb@vimeo.com>
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
When skip_frame is set to _NONKEY the decoder skips everything except intra
slices, which breaks frames that consist of an intra field together with any
other field type; half the frame becomes garbage. This patch fixes the issue by
letting non-intra slices through if they're part of a keyframe.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
That function currently does two things -- reinitializing the DSP
contexts and setting low_delay based on the SPS values.
The former more appropriately belongs in h264_slice_header_init(), while
the latter only really makes sense in decode_slice_header().
The third call to ff_h264_set_parameter_from_sps(), done immediately
after parsing a new SPS, appears to serve no useful purpose, so it is
just dropped.
Also, drop now unneeded H264Context.cur_chroma_format_idc.
Currently, the DPB is initialized in alloc_tables() and uninitialized in
free_tables(), but those functions manage frame size-dependent
variables, so DPB management does not logically belong in there.
Since we want the init/uninit to happen exactly once per the context
lifetime, init_context()/free_context() are the proper place for this
code.
The generic code copies the main context's private data to all the
others. However that is quite dangerous, as it might end up copying some
pointers that are or will become invalid.
Since everything we actually need will be copied later in
update_thread_context(), it's safest to zero the private data in
init_thread_copy(), so it works the same way as init for the main
context.
