Solving visual features' correspondence and dealing with missing data are two factors of limitations for points registration techniques. To tackle this problem, we conceived a pattern, primarily designed for structured lighting vision systems, which may also be used for camera calibration purposes. The pattern design previously presented provides a huge of benefits. Among them, we firstly present a new calibration technique of a structured lighting system and secondly an automatic distortion compensation based on a printed pattern. These two well-known issues are very useful in 3D vision-based metrology with range data, for instance for model-based visual robot control, especially when the model is incrementally built with a real-time 3D reconstruction of moving surfaces. Perhaps, one of the most significant profit with a high Hamming distance pattern is the ability to reliably decode its projected individual elements even if several of items are missing, as it greatly extends the range of measurements volume. A technique which solves the distortion parameters by means of a robust M-estimator algorithm is presented. It uses a printed pattern and it allows the distortion be corrected with a single view and without the computation of other (intrinsic/extrinsic) parameters, even in presence of occlusions. Experimental results, in one hand by means of a printed pattern for the distortion compensation of a rigid endoscope and on the other hand by means of a projected pattern for the calibration of the structured lighting system, show very good performance for the 3-D reconstruction.

In this paper we present a new monochromatic pattern for a robust structured light coding based on the spatial neighborhood scheme using the M-array approach. The proposed pattern is robust as it allows a high error rate characterized by an average Hamming distance higher than 6. We tackle the design problem with the definition of a small set of symbols associated to simple geometrical primitives. One of these primitives embeds the local orientation of the pattern. This is helpful while performing the search for the relevant neighborhood during the decoding process. The aim of this work is to use this pattern for the real-time 3-D reconstruction of dynamic scenes, particularly in endoscopic surgery, with fast and reliable detection and decoding stages. Ongoing results are presented to assess both the capabilities of the proposed pattern and the reliable decoding algorithm with projections onto simple 3-D scenes and onto internal structures of a pig abdomen.

In this paper we present a new pattern for the robust coding of the structured light based on the spatial neighborhood scheme and by means of the M-array approach. The pattern is robust as it allows a high error rate characterized by a Hamming distance higher than 3. We tackle the design problem with the definition of a small set of symbols associated to geometrical features with simple shapes. We benefit from the stripe, as it is one of the considered primitives, to embed the local orientation of the pattern. This is helpful while performing the search for the relevant neighborhood during the decoding process. The aim of this work is to use this pattern for the 3 - D reconstruction of dynamic scenes with fast and reliable detection and decoding stages. Ongoing results are presented to assess both the capabilities of the proposed pattern and the decoding algorithm with projections onto simple 3 - D scenes.