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Discover the world of 3D photography with this comprehensive course. Learn how to capture 3D shapes and appearances of real-world objects for various applications such as surgery simulation, teaching, clothing customization, forensics, industrial inspection, robot navigation, architecture survey, cultural heritage, archaeology, and more. Dive into camera models, calibration techniques, feature tracking, structure-from-motion, shape reconstruction methods, and advanced topics like shape-from-silhouettes and space carving. Engage in hands-on projects and paper presentations to understand the latest advancements in 3D photography. 8 Relevant
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3D photography Marc Pollefeys Fall 2008 http://www.inf.ethz.ch/personal/pomarc/courses/3dphoto/
3D Photography • Obtaining 3D shape (and appearance) of real-world objects
Motivation • Applications in many different areas • A few examples …
Surgery - simulation • simulate results of surgery • allows preoperative planning
Surgery - teaching Capture models of surgery for interactive learning
Clothing • Scan a person, custom-fit clothing
Forensics • Crime scene recording and analysis
3D urban modeling UNC/UKY UrbanScape project
Industrial inspection • Verify specifications • Compare measured model with CAD
Scanning industrial sites as-build 3D model of off-shore oil platform
Robot navigation ESA project our task: Calibration + Terrain modelling + Visualization small tethered rover pan/tilt stereo head
Architecture Survey Stability analysis Plan renovations
Architecture Survey Stability analysis Plan renovations
Cultural heritage Virtual Monticello Allow virtual visits
Cultural heritage Stanford’s Digital Michelangelo Digital archive Art historic studies
Archaeology accuracy ~1/500 from DV video (i.e. 140kb jpegs 576x720)
Archaeology • Record different excavation layers Generate 4D excavation record Layer 2 Layer 1 • Generate & verify construction hypothesis
Course objectives • To understand the concepts that allow to recover 3D shape from images • Explore the state of the art in 3D photography • Implement a 3D photography system/algorithm
Material Slides and more http://www.inf.ethz.ch/personal/pomarc/courses/3dphoto/ Also check out on-line “shape-from-video” tutorial: http://www.cs.unc.edu/~marc/tutorial.pdf http://www.cs.unc.edu/~marc/tutorial/ Other interesting stuff: • Book by Hartley & Zisserman, Multiple View Geometry • Peter Allen’s 3D photography class webpage http://www1.cs.columbia.edu/~allen/F07/schedule.html
Learning approach • Lectures: • cover main 3D photography concepts and approaches. • Exercice sessions: • Assignments (1st half semester) • Paper presentations and project updates (2nd half semester) • 3D photography project: • Choose topic, define scope (1st half semster) • Implement algorithm/system (2nd half semester) Grade distribution • Assignments & paper presentation: 50% • Course project: 50%
Content • camera model and calibration • single-view metrology • triangulation • epipolar geometry, stereo and rectification • structured-light, active techniques • feature tracking and matching • structure-from-motion • shape-from-silhouettes • space-carving • …
Fast Forward! • Quick overview of what is coming…
Camera models and geometry Pinhole camera or Geometric transformations in 2D and 3D
Camera Calibration • Know 2D/3D correspondences, compute projection matrix also radial distortion (non-linear)
Single View Metrology Antonio Criminisi
Feature tracking and matching Harris corners, KLT features, SIFT features key concepts: invariance of extraction, descriptors to viewpoint, exposure and illumination changes
L2 M? M Triangulation m2 l2 C2 3D from images m1 C1 L1 • calibration • correspondences
Epipolar Geometry Fundamental matrix Essential matrix Also how to robustly compute from images
Stereo and rectification Warp images to simplify epipolar geometry Compute correspondences for all pixels
Structured-light • Projector = camera • Use specific patterns to obtain correspondences
Initialize Motion (P1,P2 compatibel with F) Structure from motion Initialize Structure (minimize reprojection error) Extend motion (compute pose through matches seen in 2 or more previous views) Extend structure (Initialize new structure, refine existing structure)
* * projection constraints Auto-calibration
Space-carving Only keep photo-consistent voxels
Shape-from-X Shape-from-focus Shape-from-texture time-of-flight
3D modeling and texturing Texture integration Multiple depth images Surface model patchwork texture map
Papers and discussion • Will cover recent state of the art Each student will present a paper, discussion Select paper related to project
Course project: Build your own 3D scanner! Example: Bouguet ICCV’98 Students can work in group or alone
Marc Pollefeys CAB F66 marc.pollefeys@inf.ethz.edu Tel. 044 63 23105 David Gallup CAB F64.2 gallup@cs.unc.edu Tel. 044 23061 3D photography course team