Staging texture is used for memory transfer between system and
gpu memory. Apart from d3d11{upload,download} elements, however,
it should happen very rarely.
Before this commit, d3d11bufferpool was allocating at least one
staging texture in order to calculate cpu accessible memory size,
and it wasn't freed for later use of the texture unconditionally.
But it will increase system memory usage. Although GstD3D11memory
object is implemented so that support CPU access, most memory
transfer will happen in d3d11{upload,download} elements.
By this commit, the initial staging texture will be freed immediately
once cpu accessible memory size is calculated.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-bad/-/merge_requests/1627>
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.
Even if one of downstream d3d11 elements can support dynamic-usage memory,
another one might not support it. Also, to support dynamic-usage,
both upstream and downstream d3d11device must be the same object.
D3D11 dynamic texture is a special memory type, which is mainly used for
frequent CPU write access to the texture. For now, this texture type
does not support gst_memory_{map,unmap}
* Create staging texture only when the CPU access is requested.
Note that we should avoid the CPU access to d3d11 memory as mush as possible.
Incoming d3d11upload and d3d11download will take this GPU memory upload/download.
* Upload/Download texture memory from/to staging only if it needed, similar to
GstGL PBO implementation.
* Define more dxgi formats for future usage (e.g., color conversion, dxva2 decoder).
Because I420_* formats are not supported formats by dxgi, each plane should
be handled likewise GstGL separately, but NV12/P10 formats might be supported ones.
So we decide the number of d3d11memory per GstBuffer for video memory depending on
OS version and dxgi format. For instance, if NV12 is supported by OS,
only one d3d11memory with DXGI_FORMAT_NV12 texture can be allocated by this commit.
One use case of such texture is DXVA. In case DXVA decoder, it might need to produce decoded data
to one DXGI_FORMAT_NV12 instead of seperate Y and UV planes.
Such behavior will be controlled via configuration of GstD3D11BufferPool and
default configuration is separate resources per plane.
Do not accept any GstD3D11Device context which has different adapter
index from the required one. For example, if a d3d11 element is expecting
d3d11 device with adapter 1 (i.e., the second GPU), any d3d11 device
context having different adapter could not be shared with
the d3d11 element.
Direct3D11 was shipped as part of Windows7 and it's obviously
primary graphics API on Windows.
This plugin includes HDR10 rendering if following requirements are satisfied
* IDXGISwapChain4::SetHDRMetaData is available (decleared in dxgi1_5.h)
* Display can support DXGI_COLOR_SPACE_RGB_FULL_G2084_NONE_P2020 color space
* Upstream provides 10 bitdepth format with smpte-st 2084 static metadata
