Study On Real-time Modeling And Related Technique In Spatial Augment Reality

Augmented reality is a system which using computer auxiliary information to reinforce the reality world for users. This kind of system generates the information of graph, image and voice to the environment the user located. And these information compose the virtual world and real world into a mixed reality world, which makes user confuse between virtual and reality. Spacious augmented reality based projector took the virtual reality important and the emerging branch, in domains of military, medical service, industry, daily life and entertainment and so on. It had the broad application prospect, started to become the research hot spot gradually.Reconstruction 3D information realistically has been the important topic in computer graphics, computer vision and augmented reality. Along with the technical unceasing progress, the industrial world has higher request regarding high-accuracy, high-speed and more-integrity in reconstruction 3D information. The structured-light method is widely used in industry for its advantage in easiness and accurate measurement.The main research content of this paper includees the following several aspects: the principle of structured-light 3D measurement technique, and the introduction of popular structured coding pattern strategy; the realization of the dynamic phase-shifting structured-light method based on three-step phase-shifting structured light method and this paper provides a novel fast phase-shifting method using inclined-fringe, self-adapted phase decoding , the combination of unit-freq & high-freq information for phase unwrapping. For dynamic measurements with off-the-shelf devices, we improve the traditional phase-shifting structured-light method in fringe pattern, phase decoding, phase unwrapping and phase compensation. This scheme remains the advantage of traditional phase-shifting method and resolves its contradiction between high-speed and high-resolution. This paper also realizes how to align the captured 3D scanned data automatically. We adopt a two-stage registration strategy. It first retrieves two texture images from the scanned data to align and detects the features using SIFT (scale-invariant feature transform) on texture images, and a set of potential corresponding pixels is selected by means of filter based on RANSAC (random sample consensus) algorithm and Geometric constraints. The selected matches obtained are used to estimate the rigid transformation. Then, a modified ICP (iterative closest point) algorithm is applied to refine the result.The contribution of this paper as follow: first, it provided a dynamic phase-shifting structured-light algorithm, which could generate dense 3D data rapidly with off-the-shelf device; secondly, it realized a two-stage method to align 3D scanned data automatically, which achieves a robust and high performance in spacious augmented reality. The research achievement expands the application range and utilization of structured light 3D measurement technique.