Use a d3d9 device and allocator to encode in QSV.
This fixes a random crash that could only happen on Windows 7. The QSV
Deviced returned a DEVICE_FAILURE after a random amount of time with the
old method.
This fix is totally based on Shinck's QSVHelper.exe patch for OBS
Classic (see
https://obsproject.com/forum/threads/0-633b-qsvhelper-exe-was-killed-encode-failed.19230/page-3#post-161984
for more information)
This is more like a proof of concept, but that fix is currently stable
and tested more than 50 hours, with a single session of +14 hours.
That commit doesn't respect all OBS Guidelines. It is currently
recommended to wait for a more "cleaner" implementation.
When using QSV is used on a windows 7 machine with a dedicated card, you
have to fake a monitor connection to your Intel graphics to be able to
use QSV. If you do not, the initialization will fail with an error.
The error for that situation is not handled properly, and a variable
will be used while null. Instead, the function should safely return
after that error is received.
Also, do not call ClearData in the destructor unless QSV has been
properly initialized (if m_pmfxENC is null).
