基于图像的三维重建毕业论文外文翻译.doc
Image-based 3D modeling method AbstractThree-dimensional reconstruction is a basic research question of computergraphics and computer vision. In real life, 3D model reconstruction is widely used in object recognition, industrial automatic design, video games, animation, restore the original appearance of buildings and so on, while a higher reconstruction efficiency required to achieve real-time calculation .However, using software (such as 3D MAX and Maya, etc.) construct three-dimensional model by hand is a very tedious and costly work. Therefore, studying how obtain three-dimensional model directly and quickly from the real world, become a hot issue in the field.Realistic three-dimensional reconstruction is divided into active and passive methods. Active method is represented by three-dimensional scanner method. Passive method is that two-dimensional image-based three-dimensional reconstruction. Image-based 3D modeling method which has low cost, flexible and directly get the color texture, can reconstruct three-dimensional model fast and realistic. Image-based three-dimensional reconstruction is a significant work, there are automatic three-dimensional reconstruction, but reconstruction result is not satisfactory. We think that the user can interact with system, add some shape editing and increase flexibility of the system, but too many human-computer interaction will increase burden to the end user. Therefore, this work is mainly devoted to manually add the interaction of three-dimensional reconstruction of the building systems, design the corresponding algorithm to reduce end user workload. The main contributions are the following:1 .Present a building reconstruction and modeling system which allows noviceusers to create textured polygonal models from a set of photographs of a building.2. At present, the extracted information contains too many inconsistencies,missing features, and unwanted noise to be completely reliable. Therefore, we aim at creating a semi-automatic solution which helps reduce steps in footprint drawing process and increase the accuracy of the result.3. Exacting building footprint from point cloud. We have designed an algorithmto predict the continuation of a user-traced line segment, and provided visual cue to assist the drawing process. As the user moves the mouse, the system displayscorresponding points in the image to help the user draw the first line segment.Once the first line segment is drawn, the system, given a set of adaptive parameters, uses Hough transform and least-square fitting methods to automatically deduce subsequent line segments.User can then opt to confirm or reject the deduced line segments.Keywords:Image-based 3D Reconstruction; 3D Model;Point Cloud; Building Footprint 基于图像的三维重建摘要 三维模型获取是计算机视觉和计算机图形学领域的一个基本研究问题。在实际生活当中，3D模型的重建广泛应用于对象识别，工业自动设计，视频游戏，动画制作，建筑物原貌恢复等方面，同时要求重构有较高的效率以实现实时计算。然而，利用建模软件(比如Maya和3D MAX等)手工构建三维模型是十分繁琐和代价昂贵的工作。因此，研究如何从现实世界直接和快速地获取三维模型，成为该领域的研究热点。 基于现实物体的三维模型获取方法主要分为主动方法和被动方法。其中，主动方法以使用三维扫描仪的方法为代表。被动方法是基于二维图像的三维重建方法。基于图像的三维建模方法具备低成本，灵活和直接获取彩色纹理等特点，能够快速，逼真的重建出场景的三维模型。 基于图像的三维重建是一个有意义的工作，目前有全自动的三维重建，但是重建效果不理想。我们认为可以加上用户的交互，添加形状编辑部分，增加系统的灵活性，但是过多的人机交互又会增加用户的负担。因此，本文的工作主要就是针对添加了手动交互操作的建筑物的三维重建系统，设计相应的算法，减少用户的工作量。 本文的主要工作包括: 1.介绍了一种新的基于图像的建筑物的三维重建方案，可以让普通用户，利用普通的相机拍摄一组建筑物的图片来得到带有纹理的建筑物的三维模型。 2.提出了更人性化的交互设计，系统前两个阶段得到的三维点云数据，相对于三维扫描仪获取的精确点云，是不均匀，稀疏的，且包含一些误差，对三维模型的重建造成一定困难。由于大部分的基于计算机自动的重建方法效果不是很好，我们在重建过程中适当的增加人为交互的方法。通过人工辅助，一方面可以使算法更加简单，另一方面，也可以使重建的效果更好。3.提出了基于点云数据的建筑物的足迹提取，由于点云数据的稀疏性和不精确性，首先对对象进行分类，针对分类的对象，设计相应的算法。即在用户画足迹之前，在鼠标移动过程中，系统显示相应的点在图像中的位置，帮助用户理解点云数据;用户输入第一条建筑物的足迹线段后，利用霍夫变化和最小二乘拟合等方法推测出其它的足迹线段;并且给出了一套自适应的参数;然后用户对系统给出的足迹进行选择。关键字:基于图像的重建;三维模型;点云数据;建筑物足迹
