It involves less allocations, in particular no allocations
after the entry has been created. Therefore creating a new
reference from an existing one can't fail and therefore
need not be checked. It also avoids indirections and casts.
Also note that nvdec_decoder_frame_init() (the callback
to initialize new entries from the pool) does not use
atomics to read and replace the number of entries
currently used by the pool. This relies on nvdec (like
most other hwaccels) not being run in a truely frame-threaded
way.
Tested-by: Timo Rothenpieler <timo@rothenpieler.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Avoids allocations and error checks as well as the boilerplate
code for creating an AVBuffer with a custom free callback.
Also increases type safety.
Reviewed-by: Anton Khirnov <anton@khirnov.net>
Tested-by: Timo Rothenpieler <timo@rothenpieler.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
With the introduction of HEVC 444 support, we technically have two
codecs that can handle 444 - HEVC and MJPEG. In the case of MJPEG,
it can decode, but can only output one of the semi-planar formats.
That means we need additional logic to decide whether to use a
444 output format or not.
The 'simple' hwaccels (not h.264 and hevc) all use the same bitstream
management and reference lookup logic so let's refactor all that into
common functions.
I verified that casting a signed int -1 to unsigned char produces 255
according to the C language specification.
Some parts of the code are based on a patch by
Timo Rothenpieler <timo@rothenpieler.org>
Merges Libav commit b9129ec466.
Due to the name clash with our cuvid decoder, rename it to nvdec.
This commit also changes the Libav code to dynamic loading of the
cuda/cuvid libraries.
Signed-off-by: Timo Rothenpieler <timo@rothenpieler.org>