Download presentation
Presentation is loading. Please wait.
1
Behavior Classification by Eigen-decomposition of Periodic Motions Michael Rudzsky Joint work with Roman Goldenberg, Ron Kimmel, Ehud Rivlin Computer Science Department Technion-Israel Institute of Technology Geometric Image Processing Lab
2
Dynamism of a Dog on a Leash Giacomo Balla, 1912
3
The Red Horseman Carlo Carra, 1914
4
Muybridge Horse Eadweard Muybridge, Animals in Motion, 1887
5
Horse - decomposition
6
Segmentation and Tracking qActive Contour qFast Geodesic Active Contours uAOS uLevel Sets uFast Marching Goldenberg, Kimmel, Rivlin, Rudzsky, IEEE T-IP 2001
7
Tracking in color movies Goldenberg, Kimmel, Rivlin, Rudzsky, IEEE T-IP 2001
8
Background qBackground subtraction Chan, Vese, Active Contours without Edges, IEEE T-IP 2001 Paragios, Deriche, Geodesic Active Regions for Motion Estimation and Tracking, ICCV-99
9
Tracking
12
Information extraction
13
Walking man - periodicity
14
Walking cat -periodicity
15
Periodicity Analysis tt+3t+6t+9 +3 +6 +9
16
Inter-frame correlation
17
Spatial Alignment 50x50
18
Temporal Scaling Original period - 11 frames Resampled period - 10 frames
19
Temporal Alignment
20
Parameterization qn - number of frames in the training set q50x50 - normalized images qM 2500 x n - training samples matrix MM T = U V T, the principle basis {U i, i=1..k}
21
Distinguishing by static appearance qImage I written as a vector v I qParameterized representation in basis B, p = B T v I qDTFS ||p - v I ||
22
Back-projection Original 11 frame one period subsequence Projection to the `dogs & cats’ basis and the DTFS values
23
Recognizing motions q{I f, f=1..T} - one period, temporally aligned set of normalized object images qp f, f=1..T - projection of the image I f onto the principal basis B of size k qOne-period subsequence representation Vector P of size kT - (p f, f=1..T) qIf k = 20 and normalized duration of one-period is T=10, then P is of size 200.
24
Classification -dogs & cats walkrungallopcat...
25
Classification -dogs & cats
26
Classification -people walkrunrun45
27
Classification -people
28
Learning curves Dogs and catsPeople
29
Parameterized modeling Ju, Black, Yacoob, Cardboard People, ICFG-96 Black, Yacoob, Parameterized Modeling and Recognition of Activities, ICCV-98
30
Optical Flow Polaba, Nelson, Recognizing Activities, ICPR-94
31
Motion History Images (MHI) James W. Davis, OSU Motion Recognition Lab
32
Star Skeleton Distance from the center of mass After low pass filter
33
Phase portrays Shavit, Jepson, Motion Understanding from Qualitative Visual Dynamics, 1993
34
Summary qSegmentation uactive contours qPeriodicity analysis uglobal contour characteristics qAlignment uspatial utemporal qParameterization uPrincipal basis projection qClassification uNearest neighbors
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.