1. A vision system of a vehicle, said vision system comprising: at least one camera disposed at a vehicle and having a field of view exterior of the vehicle, wherein the field of view encompasses a first region exterior of the vehicle and a second region exterior of the vehicle; wherein said camera captures image data and wherein captured image data includes a first set of image data representative of the first region of the field of view and a second set of image data representative of the second region of the field of view; an image processor operable to process image data captured by said camera; wherein said image processor processes the first set of image data to detect a pedestrian present in the first region of the field of view based on a first predetermined orientation of a pedestrian; and wherein said image processor processes the second set of image data to detect a pedestrian present in the second region of the field of view based on a second predetermined orientation of a pedestrian.