Video Alignment

1
Video Alignment

• Presented by
• Omer Shakil

2
Introduction

• Problem Statement
• Alignment Techniques
• Direct-Based Caspi and Irani, 2000 and 2002
• Feature-Based Stein, 1998
• Best Frame Pair Search Sand and Teller, 2004
• Non-Overlapping Sequences
• Coherent Temporal Behavior Caspi and Irani, 2001
  and 2002

3
Algorithm Caspi and Irani, 2002

• Video Sequences S and S
• Inter-Camera Homography
• Inter-Frame Transformation Ti between Ii and Ii1
• Derive
• or
• Hence
• Least Square Minimization

4
Algorithm (continued)

• Mi is a 9 x 9 matrix defined by Ti, Ti and si
• Combining all the constraints
• H Eigen-vector of ATA corresponding to the
  smallest eigen-value.

5
Extension

• Learning Phase
• Recover Inter-Camera Homography
• Free Camera Movement
• Frame Registration
• Reference Frame from the Learning Phase
• Future Work
• 3D Scenes
• Synchronization

Input Sequences
6
Results - Finding Transformations Bergen, et.
al., 1992
Images
Scaling
Translation
Rotation
Actual
Recovered