We have recently started encountering some errors from the H264 encoder based on the MFX SDK sample DirectShow filters.
The specific error is this:
Return on error: error code: -2147220992 .\src\mfx_video_enc_filter.cpp 503
There are usually two of these errors in most cases followed by a generic unexpected error code on issuing the Run() method to the DirectShow filter graph. So in those cases capture never starts. However, in a few other cases the capture does start but it is in black & white (despite preview being full color).
In one instance (on one machine) I was able to isolate the issue to a combination of drivers. The computer has an Intel i3 processor with Intel HD 4600 graphics on board and a dedicate NVidia GeForce GTX 645 graphics card. If only the Intel drivers are installed then no errors come up. However whenever the NVidia drivers are also installed on the machine the errors above are thrown and capture doesn't work. The order of installation for the drivers does not matter - we have tried both. I should also mention that his computer has dual screens - one connected to the Intel on-board graphics, the other to the NVidia card.
On that machine we have tried the latest Intel graphics drivers (10.18.14.4156) and the most recent NVidia drivers (22.214.171.12452).
The issue has also happened on a different machine - a Microsoft Surface 3 tablet. Which only has the Intel graphics card installed. On the tablet I was not able to update the drivers from the Intel website.