Suggestions / Tips for my Line crossing settings ( check picture )

[normel]

This is the camera, places in front of the door. I have set the line crossing, and ofcourse i want as less as possible falls alarms ( Lights of cars parking, and driving by )
What sensitivty do you suggest for best performance?

 

[normel]

just for in is enough. i already changed a >b
unfortunately i am getting false alarm cuz if car lights parking or turning
i will try lower senstvry