1. A computerized method for placing an annotation on an image of a scene, comprising the steps of: (a) obtaining an original image of said scene with a camera; (b) determining a geographic location of said camera with a location sensor; (c) determining an orientation of the camera with a compass; (d) using either one of a computer vision algorithm or an image processing technique to determine similarities between visual features of said image and a reference images or models; (e) determining a first probability that one said visual feature at a first position in said image corresponds to said reference image or model, based on said geographic location determined from said location sensor, on information from said one of said computer vision algorithm or said image processing technique, and on the orientation of the camera; (f) determining a second probability that one said visual feature at at least a second position in said image corresponds to said reference image or model, based on said geographic location determined from said location sensor, on information from said one of said computer vision algorithm or said image processing technique, and on the orientation of the camera; (g) obtaining an annotation for said reference image of model; (h) determining an annotation position suitable for annotating said first position if said first probability is the highest, or suitable for annotating said second position if said second probability is the highest; (i) forming an annotated image by including said annotation at said annotation position.