We propose a fast calibration method for projector-camera pairs which does not require any special calibration objects or initial estimates of the calibration parameters. Our method is based on a structured light approach to establish correspondences between the camera and the projector view. Using the vanishing points in the camera and the projector view the internal as well as the external calibration parameters are estimated. In addition, we propose an interactive projection mapping scheme which allows the user to directly place two-dimensional media elements in the tangent planes of the target surface without any manual perspective corrections.

This paper covers a fundamental problem of local phase based signal processing: the isotropic generalization of the classical 1D analytic signal to two dimensions. The well known analytic signal enables the analysis of local phase and amplitude information of 1D signals. Local phase, amplitude and additional orientation information can be extracted by the 2D monogenic signal with the restriction to the subclass of intrinsically one dimensional signals. In case of 2D image signals the monogenic signal enables the rotationally invariant analysis of lines and edges. In this work we present the 2D analytic signal as a novel generalization of both the analytic signal and the 2D monogenic signal. In case of 2D image signals the 2D analytic signal enables the isotropic analysis of lines, edges, corners and junctions in one unified framework. Furthermore, we show that 2D signals exist per se in a 3D projective subspace of the homogeneous conformal space which delivers a descriptive geometric interpretation of signals providing new insights on the relation of geometry and 2D signals.