Resolving SunplusIT Integrated Camera issue in Lenovo laptops
Recent driver upgrade to >=5.0.18.240 in Windows made the camera turn on briefly then output a blank stream.
Issue happens to be with sgl_mnn_dll.dll, which is responsible for face and landmark detection. To fix, replace this file in C:\WINDOWS\system32\ with an older version. The latest version that worked for me was 5.0.18.200. Find other versions on Microsoft Update Catalog with search query 'Sunplus'.
Also, a directory that might be handy is where the driver is installed in DriverStore/FileRepository/. Device Manager also shows where driver files are installed.