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This seminar presented by Anton Jigalin delves into the advanced topics of scene reconstruction and visualization within the realm of computer vision. It explores methods for automatically reconstructing 3D geometry from extensive online photo collections. Key challenges such as unknown camera positions, correspondence problems, and algorithmic complexity are examined alongside innovative solutions like image-based modeling and Structure from Motion (SfM). The seminar also introduces tools for 3D navigation and scene annotation, enhancing the overall photo tourism experience.
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Scene Reconstruction Seminar presented by Anton Jigalin Advanced Topics in Computer Vision (048921)
SceneReconstruction SceneVisualization: Photo Tourism:3D photo browser PathFinder:3D navigation interface References: Scene Reconstruction and Visualization from Internet Photo Collections. N. Snavely. 2008.
The goal Automatically reconstruct 3D geometry from large collections of photos from the Internet
Motivation • New way to organize photo collections • Experience of being at a place
Related works • Image based modeling • Moviemaps • Structure from motion (SfM)
Challenges • Unknown cameras position • Unknown internal camera parameters • Correspondence problem • Visualization • Algorithmic complexity Running the complete pipeline on a 3.80GHz Intel Xeon machine with 4GB of core memory. The keypoint detection and matching phases were run in parallel on 10 such machines.
Finding correspondence • Feature detection - SIFT • Feature matching - RANSAC • Epipolar constraint
Structure from Motion Algorithm • Initial two-frame • reconstruction • Intermediate stage • Final reconstruction
Failure modes • Repeating textures • Insufficient overlap or texture • Cascading errors • Bad initialization
SceneVisualization: Photo Tourism:3D photo browser
Photo Tourism: Main components • Rendering engine • Navigation interface • Tools for scene annotation
Navigation interface • Object-based navigation • Stabilized slideshow
Scene annotation • Register new photographs • Annotate regions
SceneVisualization: PathFinder:3D navigation interface
Best possible controls • The goals of 3D navigation: • Exploration • Search • Object inspection • Principles for 3D scene navigation: • Controls are scene and task dependent • Constrained and automatic navigation • User’s position and motion should be clear
Pathfinder: Main components • Viewpoint scoring • Navigation controls for a scene • Rendering engine • User interface
Scene-specific controls: Panoramas and Orbits • Panoramas • Orbits
Path planning • Connectivity graph • High-quality rendering • Shortest path • Piecewise linear path • Path smoothing
Limitations • Non circular orbits • User needs • Appearance compensation • Larger scenes Pisa Doumo Stonehenge
Conclusion • Structure from motion • Photo Tourism - 3D photo browser • Path Finder - 3D navigation system Future work • Reconstructing Rome • Capturing appearance • New photo-sharing community