/usr/lib/x86_64-linux-gnu/dri/s3g_drv_video.so is in vdpau-va-driver 0.7.4-5.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/lib/x86_64-linux-gnu/dri/vdpau_drv_video.so
/usr/lib/x86_64-linux-gnu/dri/vdpau_drv_video.so