3D-Modeling by Ortho-Image Generation from Image Sequences

1
3D-Modeling by Ortho-Image Generation from Image
Sequences

• Thorsten Thormahlen Hans-Peter Seidel
• Max Planck Institute for Computer Science,
  Saarbrucken, Germany
• ACM SIGGRAPH 2008

2
Introduction

• Fast interactive generation of 3D models from
  image sequences
• Generate high-quality 3D model of a static object
  from an image sequence
• It canbe generated for translucent or specular
  surfaces

3
Introduction

This paper
4
Outline

• Introduction
• Placement of the Bounding box
• Ortho-image Generation
• Ortho-images without geometry
• Ortho-images with approximate geometry
• Results
• Conclusion

5
Placement of the Bounding box

• 4 4 matrix H describes the anisotropic
  similarity transformation, which has 9
  parameters, 3 each for position, rotation, and
  anisotropic scaling.

6
Ortho-images without geometry

• If many camera views are available
• Determine the color intensity for that pixel
  directly
• if min?Cj lt t2? .

7
Ortho-images with approximate geometry

• If many min?Cj gt t
• Then the color intensity of the pixel is
  determined by projecting a ray from the camera
  center Cj to the point
• But we need approximate geometry now!!

8
Ortho-images with approximate geometry

• Graph-cut approach for multi-view stereo
  in Vogiatzis et al. 2005
• For each of the voxels, a photo-consistency score
  is calculated
• The graph-cut algorithm ?nds a cut through the
  edges of the graph

9
Result

• video display

10
Conclusion

• Semi-automatic approach
• High-quality and accurate 3D models from image
  sequences
• Allow specular or transparent objects