Subpixel Scanning Invariant to Indirect Lighting Using Quadratic Code Length

We present a scanning method that recovers dense sub pixel camera-projector correspondence without requiring any photometric calibration nor preliminary knowledge of their relative geometry. Sub pixel accuracy is achieved by considering several zero-crossings defined by the difference between pairs of unstructured patterns. We use gray-level band-pass white noise patterns that increase robustness to indirect lighting and scene discontinuities. Simulated and experimental results show that our method recovers scene geometry with high sub pixel precision, and that it can handle many challenges of active reconstruction systems. We compare our results to state of the art methods such as micro phase shifting and modulated phase shifting.