A DPB buffer held by codec picture object may not be writable
at the moment, then gst_buffer_make_writable() will unref passed buffer.
Specifically, the use after free or double free can happen if:
* Crop meta of buffer copy is required because of non-zero
top-left crop position
* zero-copy is possible with crop meta
* A picture was duplicated, interlaced h264 stream for example
Interlaced h264 stream with non-zero top-left crop position
is not very common but it's possible configuration in theory.
Thus gst_buffer_make_writable() should be called with
GstVideoCodecFrame.output_buffer directly.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6710>
Do not chain up to parent's GstBufferPool::start() which will do
preallocation. We don't want it to be preallocated
since there are various cases where negotiated downstream buffer pool is
not used at all (e.g., zero-copy decoding, IPC elements).
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6345>
Gets being released memory back to queue even if allocator is flushing
in order to count the number of outstanding memory objects.
Also, clear queue if there's no outstanding memory object and
allocator is flushing
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6240>
According to recommendation from MS, IDXGIOutputDuplication::ReleaseFrame()
needs to be called just before IDXGIOutputDuplication::AcquireNextFrame()
for performance reasons, so that driver can accumulate dirty rects
and update texture at once. But it seems to cause choppy output.
Do release acquired frame immediately once processing done,
like d3d11 implementation does.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6092>
Fence data could hold GstD3D12Device directly or indirectly.
Then if it's holding last refcount, the device object will
be released from the device object's internal thread,
and will try join self thread.
Delegates it to other global background thread to avoid
self thread joining.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6042>
Fixing below debug layer report
ID3D12Device::CreateCommittedResource: Ignoring InitialState D3D12_RESOURCE_STATE_COPY_DEST.
Buffers are effectively created in state D3D12_RESOURCE_STATE_COMMON.
Buffer resource will be automatically promoted to D3D12_RESOURCE_STATE_COPY_DEST
at the very first COPY operation time.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5895>
Since DXGI desktop duplication API does not work with Direct3D12 device,
this element will use Direct3D11 device to acquire frame.
Then other rendering operations (e.g., texture copy, render pipeline) will
happen using Direct3D12 API
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5883>
In case of tier 1 decoder, always use reference-only picture to avoid
fixed-size pool limitation and output decoded picture without
copy even for negative rate. Also do not use copy queue for GPU to GPU
copy. Copy queue is specialized for upload/download and may occupy
PCIE bandwidth. Use direct queue as recommended by vendors.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5877>
On flush event, baseclass will discard all pictures from DPB
but there can be still in-flight commands not finished yet.
Use our command queue, allocator and fence data helper objects
to keep resource available during command execution.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5877>
Shader visible descriptors occupy GPU resource and there are hardware
limits. Thus, in order to minimize the amount of shader visible heaps,
only non shader visible descriptor heap (staging) will be held by d3d12memory.
Then converter will copy the staging descriptor to shader visible
descriptor heap per draw.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5875>
Zero initialization would have overhead and it's not required
most cases except for textures. Use CREATE_NOT_ZEROED flag
in case of buffer resource or if a texture will be rendered without any
prior read operation.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5875>
Conversion will happen when constructed command list is executed,
not by converter element. Thus this object should not map output buffer
with write flag which will result in error if multiple threads
are building commands for the same output target frame.
Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/5875>
