Camera calibration without metric information using 1D objects

This paper addresses the problem of calibrating a pin-hole camera from images of 1D objects. Assuming a unit aspect ratio and zero skew, we introduce a novel and simple approach that uses four observations of a 1D object and requires no information about the distances between the points on the object. This is in contrast to existing methods that use two images, but impose more restrictive configurations that require measured distances on the calibrating object. The key features of the proposed technique are its simplicity and ease of use due to the lack of need for any metric information. To demonstrate the effectiveness of the algorithm, we present the processing results on synthetic and real images.