lecture20 - 1 Global Flow Global Flow • Dominant Motion...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 Global Flow Global Flow • Dominant Motion in the scene • Motion of all points in the scene • Motion of most of the points in the scene • A Component of motion of all points in the scene • Global Motion is caused by • Motion of sensor (Ego Motion) • Motion of a rigid scene • Estimation of Global Motion can be used to • Video Mosaics • Image Alignment (Registration) • Removing Camera Jitter • Tracking (By neglecting camera motion) • Video Segmentation etc. 2 Global Flow Application: Image Alignment Estimation of Global Flow James R. Bergen, P. Anandan, Keith J. Hanna, Rajesh Hingorani: “Hierarchical Model-Based Motion Estimation," ECCV 1992: 237-252 Assume Affine Flow: 2 4 3 1 2 1 b y a x a v v b y a x a v u B y x A v u y x + + = = + + = = + & ¡ ¢ £ ¤ ¥ = & ¡ ¢ £ ¤ ¥ & & & & & & & & ¡ ¢ £ £ £ £ £ £ £ £ ¤ ¥ & ¡ ¢ £ ¤ ¥ = & ¡ ¢ £ ¤ ¥ 2 4 3 1 2 1 1 1 b a a b a a y x y x v u Xa U = 3 Estimation of Global Flow ( 29 = + & ¡ ¢ £ ¤ ¥ ∇ t T I v u I (Optical Flow Constraint Equation) ( 29 = + ∇ t T I I Xa ( 29 [ ] ( 29 , 2 = + ∇ ¦ ∈ 2200 I y x t T I I Xa ( 29 [ ] ( 29 ¦ ∈ 2200 + ∇ I y x t T I I , 2 min Xa ( 29 ( 29 ( 29 ( 29 ¦ ¦ ∈ 2200 ∈ 2200 ∇- = & ¡ ¢ £ ¤ ¥ ∇ ∇ I y x T t I y x T T I I I I , , X a X X B Aa = Estimation of Global Flow Single Iteration Image ‘t’ Image ‘t+1’ Warp by a B Aa = Solve Compute A and B 4 Estimation of Global Flow Iterative Image ‘t’ Image ‘t+1’ Warp by a Initial Estimate [ ] T b a a b...
View Full Document

This note was uploaded on 06/12/2011 for the course CAP 5415 taught by Professor Staff during the Fall '08 term at University of Central Florida.

Page1 / 15

lecture20 - 1 Global Flow Global Flow • Dominant Motion...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online