A surround view system for a vehicle, the vehicle having a trailer attached thereto, comprising: a plurality of cameras (18, 18', 18") mounted on the vehicle and constructed and arranged to provide generally a 360° view of an area surrounding the vehicle, an electronic control unit (ECU) mounted on the vehicle and constructed and arranged to receive image data from the cameras (18, 18', 18"), the ECU including a processor circuit and a memory circuit, the memory circuit being constructed and arranged to store a legacy observable image of the area obtained from the cameras (18, 18', 18") as the vehicle passed through a portion of the area in one direction and is further being moved through the area, and a display connected with the ECU for displaying a surround view image to a driver of the vehicle, the surround view image including an obstruction in the area occluding at least a portion of a field of view of at least one of the cameras (18, 18', 18") positioned on a rear portion of the vehicle thereby defining an unobservable region, with the trailer defining the obstruction, wherein, after the vehicle has passed through the portion of the area and is further being moved through the area in reverse to back-up the trailer, and when there is an obstruction in the area occluding at least a portion of a field of view of at least one of the cameras (18, 18', 18"), based on the legacy observable image, live images obtained from the cameras (18, 18', 18") and on a geometry of the obstruction, the processor circuit is constructed and arranged to calculate at least one unobservable region in the area based on a comparison of the legacy observable image and live images, and to cause the unobservable region to be indicated in the surround view image on the display, wherein the unobservable area includes a color filter indicative of a lack of visibility of dynamic targets entering the unobservable area. a plurality of cameras (18, 18', 18") mounted on the vehicle and constructed and arranged to provide generally a 360° view of an area surrounding the vehicle, an electronic control unit (ECU) mounted on the vehicle and constructed and arranged to receive image data from the cameras (18, 18', 18"), the ECU including a processor circuit and a memory circuit, the memory circuit being constructed and arranged to store a legacy observable image of the area obtained from the cameras (18, 18', 18") as the vehicle passed through a portion of the area in one direction and is further being moved through the area, and a display connected with the ECU for displaying a surround view image to a driver of the vehicle, the surround view image including an obstruction in the area occluding at least a portion of a field of view of at least one of the cameras (18, 18', 18") positioned on a rear portion of the vehicle thereby defining an unobservable region, with the trailer defining the obstruction, wherein, after the vehicle has passed through the portion of the area and is further being moved through the area in reverse to back-up the trailer, and when there is an obstruction in the area occluding at least a portion of a field of view of at least one of the cameras (18, 18', 18"), based on the legacy observable image, live images obtained from the cameras (18, 18', 18") and on a geometry of the obstruction, the processor circuit is constructed and arranged to calculate at least one unobservable region in the area based on a comparison of the legacy observable image and live images, and to cause the unobservable region to be indicated in the surround view image on the display, wherein the unobservable area includes a color filter indicative of a lack of visibility of dynamic targets entering the unobservable area.