Use the flags argument of av_hwframe_ctx_create_derived() to pass the
mapping flags which will be used on allocation. Also, set the format
and hardware context on the allocated frame automatically - the user
should not be required to do this themselves.
(cherry picked from commit c5714b51aa)
Some frames contexts are not usable without additional format-specific
state in hwctx. This change adds new functions frames_derive_from and
frames_derive_to to initialise this state appropriately when deriving
a frames context which will require it to be set.
(cherry picked from commit 27978155bc)
Adds functions to convert to/from strings and a function to iterate
over all supported device types. Also adds a new invalid type
AV_HWDEVICE_TYPE_NONE, which acts as a sentinel value.
(cherry picked from commit b7487f4f3c)
This adds tons of code for no other benefit than making VideoToolbox
support conform with the new hwaccel API (using hw_device_ctx and
hw_frames_ctx).
Since VideoToolbox decoding does not actually require the user to
allocate frames, the new code does mostly nothing.
One benefit is that ffmpeg_videotoolbox.c can be dropped once generic
hwaccel support for ffmpeg.c is merged from Libav.
Does not consider VDA or VideoToolbox encoding.
Fun fact: the frame transfer functions are copied from vaapi, as the
mapping makes copying generic boilerplate. Mapping itself is not
exported by the VT code, because I don't know how to test.
* commit 'fdfe01365d579189d9a55b3741dba2ac46eb1df8':
hwcontext: allocate the destination frame for the pool size
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>
Adds the new av_hwframe_map() function, which allows mapping between
hardware frames and normal memory, along with internal support for
implementing it.
Also adds av_hwframe_ctx_create_derived(), for creating a hardware
frames context associated with one device using frames mapped from
another by some hardware-specific means.
The source frame may be cropped, so that its dimensions are smaller than
the pool dimensions. The transfer_data API requires the allocated size
of the destination frame to be the same as the pool size.
