Can anyone help me with vision toolbox this 2010 code for vehicle counting

I have tried to learn code from below link,this executes too; but unable to understand counter_vehicle.m and usage of Lim_fi,ci,fd,cd,and assigned values for them ,someone please help me with this ,credits to www.matpics.com and everyone who answers this

[Jaswanth kumar Jalagam]

https://in.mathworks.com/matlabcentral/fileexchange/49554-traffic-surveillance-using-image-processing?s_tid=answers_rc2-1_p4_MLT