1. A computer-implemented method for applying computer vision techniques to automatically detect the presence of static objects within a thoroughfare crossing, the method comprising executing on a processing unit the steps of: determining whether an underlying object of foreground object image features that are extracted from input video image data of a scene of a level-grade crossing of a first thoroughfare by a second thoroughfare is in motion or is static; in response to determining that the underlying object is in motion, determining a dominant moving direction of the underlying object as a function of optical flow image features that are extracted from a region of the input video image data that is defined by the extracted foreground object image features; generating an event alarm in response to determining that the underlying object is static for a threshold time period, or in response to determining that the underlying object is in motion and the determined dominant moving direction of the underlying object is not parallel to the orientation of the second thoroughfare that is crossed by the first thoroughfare, wherein the event alarm that indicates that a static object is blocking travel on the crossing second thoroughfare; and not generating the event alarm in response to determining that the underlying object is static for less than the threshold time period, or in response to determining that the underlying object is in motion and the determined dominant moving direction of the underlying object is parallel to the orientation of the second thoroughfare that is crossed by the first thoroughfare.