mmm... nvof_grid = 0 gives a script error with "division by zero" and nvof_grid = 1 gives another script error
in fact, NVOF engine works with 4*4 px block only ![]()
so "4px" in SVP is just "search 4*4 blocks on the original frame size"
and "8px" --> "search 4*4 blocks on the frame reduced by 2 in both directions"