1. A method for determining a geometry of a scene, comprising: projecting an output image into a scene, in which a time to project the output image is t 1 ; acquiring, while projecting the output image, an input image of the scene, in which a time to acquire the input image is t 2 , and in which t 1 >t 2 , and in which the input image includes a distinguishable stripe of pixels with an edge due to t 1 >t 2 ; and measuring, in the input image, an amount of distortion d of the edge of the stripe from a straight line to determine a geometry of the scene, wherein the steps are performed in a processor.