This introduce a library which contains a set of base classes which
handles the parsing and the state tracking for the purpose of decoding
different CODECs. Currently H264, H265 and VP9 are supported. These
bases classes are used to decode with low level decoding API like DXVA,
NVDEC, VDPAU, VAAPI and V4L2 State Less decoders. The new library is
named gstreamer-codecs-1.0 / libgstcodecs.
DXVA spec is saying that the size of bitstream buffer provided by hardware decoder
should be 128 bytes aligned. And also the host software decoder should
align the size of written buffer to 128 bytes. That means if the slice
(or frame in case of VP9) size is not aligned with 128 bytes,
the rest of non 128 bytes aligned memory should be zero-padded.
In addition to aligning implementation, some variables are renamed
to be more intuitive by this commit.
This implementation is similar to what we've done for nvcodec plugin.
Since supported resolution, profiles, and formats are device dependent ones,
single template caps cannot represent them, so this modification
will help autoplugging and fallback.
Note that the legacy gpu list and list of resolution to query were
taken from chromium's code.
... and remove unused start, stop method from subclass.
Current implementation does not require subclass specific behavior
for the handle_frame() method.
Use consistent memory layout between dxva and other shader use case.
For example, use DXGI_FORMAT_NV12 texture format instead of
two textures with DXGI_FORMAT_R8_UNORM and DXGI_FORMAT_R8G8_UNORM.
This reverts commit ddd13fc7c0
Dynamic usage can reduce the number of copy per frame but make
things complicated and the benefit seems to not significant.
Also since we don't provide _map() method for the dynamic usage,
application cannot read buffers which make "last-sample" property
unusable in case of d3d11videosink.
Although the target platform of D3D11 decoding API are both desktop and UWP app,
DXVA header is blocked by "WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP)"
which is meaning that that's only for desktop app.
To workaround this inconsistent annoyingness, we need to define WINAPI_PARTITION_DESKTOP
regardless of target WinAPI partition.
