1. An image registration method, comprising: acquiring first and second distorted or partially distorted images of scenes that each include a first object; computing horizontal and vertical integral projection vectors for the first and second distorted or partially distorted images or distortion-corrected images, or both; registering the first and second distorted or partially distorted images, or the distortion-corrected images, or both, including applying a scale factor estimation between the first and second images on the horizontal and vertical integral projection vectors; and performing a further action using the registered first and second distorted or partially distorted images or the corrected images, or both.