1. A method for parking occupancy determination, said method comprising: acquiring video of an entrance to a parking lot utilizing at least one video camera focusing on a computer vision-based region of interest for vehicle validation and a video-based region of interest for motion detecting and tracking; video processing said video via at least one classifier trained with data collected from said parking lot and to take into account potential camera shake disturbances to generate video output data thereof, wherein said at least one classifier comprises at least one computer vision-based image content classifier; analyzing said video output data for parking lot occupancy data, wherein an impact of camera shake with respect to said at least one video camera is minimized to determine parking lot occupancy; determining an access type with respect to said parking lot based on said parking lot occupancy data, after analyzing said video output data for said parking lot occupancy data; configuring said at least one classifier to comprise said computer vision-based image content classifier that performs image content classification for the computer vision-based region of interest and assists in object tracking with respect to said video-based region of interest; applying distortions that simulate camera shake effects with respect to at least one image frame; cropping said at least one image frame at an original region of interest after said applying said distortions that simulate said camera shake effects with respect to said at least one image frame; incorporating said potential camera shake disturbances into training of said at least one classifier used for computer vision-based processing for said computer vision-based region of interest for vehicle validation and used for trajectory smoothing said video output data to remove an impact of high-frequency components during said camera shake disturbances; measuring changes in a field of view of said video using template matching between templates derived from at least one original scene and at least one current scene with motion removed; and employing said changes measured in said field of view to adjust data indicative of at least one region of interest for computer vision-based processing thereof if said changes measured are above a pre-determined threshold so that an impact of said changes with respect so said field of view to performance is minimized and determine said parking lot occupancy.