An Image Based Multi-View Real-Time Reconstruction System

3D surface reconstruction is an unsolved and important task in computer vision. It aims at restoring three-dimensional features from two-dimensional information and constructing the geometrical model of objects. This thesis focuses on algorithms of the three-dimensional surface reconstruction from silhouette information of objects, designs and develops a multi-view real-time 3D reconstruction system.In this thesis, multiple fixed cameras are used for collecting images of moving objects from different perspectives. By generating visual hulls with an adaptive algorithm, the surfaces of moving objects are reconstructed in real time. Our aim is to improve the accuracy, reliability and flexibility of three-dimensional reconstruction. The research has a broad prospect in 3D modeling, representation and virtual reality.First of all, this thesis introduces the research background of the area of 3D reconstruction. On this basis, with the actual needs of our system, we propose the main elements of this thesis: image pre-processing, calibration and adaptive distance field based real-time 3D reconstruction. The purpose of image pre-processing is to filter out noise from the image and to isolate useful information for follow-up processes. We adopt background subtraction and mathematical morphology algorithms to separate moving objects from background. In the research of calibration algorithm, by using Zhang's plane calibration which is between the traditional algorithm and self-calibration algorithm, we can acquire the precise parameters of cameras. In the research of reconstruction, based on the principles of Shape from Silhouette, combined with Adaptive Distance Fields, we implement the real-time reconstruction of moving objects. Finally, we analysis the system errors and bottlenecks, and introduce the scheme of future improvement.In conclusion, this thesis not only theoretically expounds an image-based real-time reconstruction algorithm, but also gives an implementation of the specific system. This research work has value of both theory and application.