There have been several reports that a library, libpxcface_idc.dll, used in the C++ Face module in RealSense SDK R3 is crashing when detecting multiple faces. We have been able to reproduce this problem when detecting multiple faces, and tracking at least one, in the C++ Face sample. The C# Face sample seems to work fine for some users, but not for others. We have not been able to reproduce this using either the C# or C++ Face samples in RealSense SDK R2.
Unfortunately, there will not be further development on the Face module for RealSense SDK for Windows so we cannot find the root cause of this issue.
As a workaround, we recommend to use RealSense SDK R2 for your Face projects that require multiple face tracking. The C# Face module in RealSense SDK R3 might work. Do not rely on libpxcface_idc.dll.
We apologize for the inconvenience this has caused.