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1 CMU SCS Image and Multimedia Mining Christos Faloutsos CMU MLD school 06 Copyright: C. Faloutsos, 2006 2 CMU SCS Outline Problem definition and motivation Indexing and feature extraction Features for images (DWT, morphology, etc) Tools and case studies: PCA, ICA, Random Walks • Conclusions MLD school 06 Copyright: C. Faloutsos, 2006 3 CMU SCS Problem #1: Similarity search [Bob Murphy] Sub-cellular protein localization patterns MLD school 06 Copyright: C. Faloutsos, 2006 4 CMU SCS Problem #1: Similarity search Nucleolar Mitoch. Actin Tubulin Endosomal MLD school 06 Copyright: C. Faloutsos, 2006 5 CMU SCS day $price 1 365 day $price 1 365 day $price 1 365 distance function? <later> Problem#1’: Similarity search: MLD school 06 Copyright: C. Faloutsos, 2006 6 CMU SCS Problem #2: Mining [Bob Murphy] Sub-cellular protein localization patterns

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Page 1: Image and Multimedia Miningchristos/TALKS/MLD-SS06/mld-ss06-v32.pdf · Searching Multimedia Databases by Content, On. •,, DWT)

1

CMU SCS

Image and Multimedia Mining

Christos Faloutsos

CMU

MLD school 06 Copyright: C. Faloutsos, 2006 2

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

• Features for images (DWT, morphology,

etc)

• Tools and case studies: PCA, ICA, Random

Walks

• Conclusions

MLD school 06 Copyright: C. Faloutsos, 2006 3

CMU SCS

Problem #1: Similarity search• [Bob Murphy] Sub-cellular protein localization patterns

MLD school 06 Copyright: C. Faloutsos, 2006 4

CMU SCS

Problem #1: Similarity search

NucleolarMitoch. Actin

TubulinEndosomal

MLD school 06 Copyright: C. Faloutsos, 2006 5

CMU SCS

day

$price

1 365

day

$price

1 365

day

$price

1 365

distance function? <later>

Problem#1’: Similarity search:

MLD school 06 Copyright: C. Faloutsos, 2006 6

CMU SCS

Problem #2: Mining• [Bob Murphy] Sub-cellular protein localization patterns

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2

MLD school 06 Copyright: C. Faloutsos, 2006 7

CMU SCS

day

$price

1 365

day

$price

1 365

day

$price

1 365

distance function? <later>

Problem#2’: Mining

MLD school 06 Copyright: C. Faloutsos, 2006 8

CMU SCS

Problem definition

• Given: many sequences (images, video-

clips)

x1 , x2 , … , xt , …

(y1, y2, … , yt, …

… )

• Find

– similar sequences / images / video-clips

– patterns; clusters; outliers

MLD school 06 Copyright: C. Faloutsos, 2006 9

CMU SCS

Motivation - applications: Images

• medical/biological images (training;

research)

• biometrics/security

• satellite image analysis

• photo collections

• museum images

• logos

• ... MLD school 06 Copyright: C. Faloutsos, 2006 10

CMU SCS

Motivation - applications: Video

• surveillance

• TV news processing (eg., summarization -www.informedia.cs.cmu.edu)

• 3-d images (medical / biological)

• 3-d and 4-d datasets (x,y,z, time, temp.,

humidity etc) - weather/environment

monitoring

MLD school 06 Copyright: C. Faloutsos, 2006 11

CMU SCS

Motivation - applications: Time

sequences• Financial, sales, economic series

• Medical (ECGs/EKGs, monitoring)

• civil infrastructure; automobile traffic

monitoring

MLD school 06 Copyright: C. Faloutsos, 2006 12

CMU SCS

Motivation

water distribution network

(w/ Jeanne Vanbriesen, CMU)

Phase 1 Phase 2 Phase 3

: : : : : :

: : : : : :

chlorine concentrations

Page 3: Image and Multimedia Miningchristos/TALKS/MLD-SS06/mld-ss06-v32.pdf · Searching Multimedia Databases by Content, On. •,, DWT)

3

MLD school 06 Copyright: C. Faloutsos, 2006 13

CMU SCS

Motivation - Applications

(cont’d)

• Weather, environment/anti-pollution

• computer network traffic monitoring

• data-center traffic monitoring (self-*

system at CMU)

MLD school 06 Copyright: C. Faloutsos, 2006 14

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

• Features for images (DWT, morphology,

etc)

• Tools and case studies: PCA, ICA, Random

Walks

• Conclusions

MLD school 06 Copyright: C. Faloutsos, 2006 15

CMU SCS

Indexing

Problem:

• given a set of time sequences,

• find the ones similar to a desirable query

sequence

MLD school 06 Copyright: C. Faloutsos, 2006 16

CMU SCS

day

$price

1 365

day

$price

1 365

day

$price

1 365

distance function: by expert

MLD school 06 Copyright: C. Faloutsos, 2006 17

CMU SCS

Idea: ‘GEMINI’

Eg., ‘find stocks similar to MSFT’

Seq. scanning: too slow

How to accelerate the search?

[Faloutsos96]

MLD school 06 Copyright: C. Faloutsos, 2006 18

CMU SCS

day1 365

day1 365

S1

Sn

F(S1)

F(Sn)

‘GEMINI’ - Pictorially

eg, avg

eg,. std

Page 4: Image and Multimedia Miningchristos/TALKS/MLD-SS06/mld-ss06-v32.pdf · Searching Multimedia Databases by Content, On. •,, DWT)

4

MLD school 06 Copyright: C. Faloutsos, 2006 19

CMU SCS

GEMINI

Solution: Quick-and-dirty' filter:

• extract n features (numbers, eg., avg., etc.)

• map into a point in n-d feature space

• organize points with off-the-shelf spatial

access method (‘SAM’)

• discard false alarms

MLD school 06 Copyright: C. Faloutsos, 2006 20

CMU SCS

Examples of GEMINI

• Time sequences: DFT (up to 100 times

faster) [SIGMOD94];

• [Kanellakis+], [Mendelzon+]

MLD school 06 Copyright: C. Faloutsos, 2006 21

CMU SCS

Examples of GEMINI

Also, on many other data types:

• Images (QBIC) [JIIS94]

• tumor-like shapes [VLDB96]

• video [Informedia + S-R-trees]

• automobile part shapes [Kriegel+97]

MLD school 06 Copyright: C. Faloutsos, 2006 22

CMU SCS

Indexing - SAMs

Q: How do Spatial Access Methods (SAMs)

work?

A: they group nearby points (or regions)

together, on nearby disk pages, and answer

spatial queries quickly (‘range queries’,

‘nearest neighbor’ queries etc)

For example:

MLD school 06 Copyright: C. Faloutsos, 2006 23

CMU SCS

R-trees

• [Guttman84] eg., w/ fanout 4: group nearby

rectangles to parent MBRs; each group ->

disk page

A

B

C

DE

FG

H

I

J

adv

MLD school 06 Copyright: C. Faloutsos, 2006 24

CMU SCS

R-trees

• eg., w/ fanout 4:

A

B

C

DE

FG

H

I

J

P1

P2

P3

P4

F GD E

H I JA B C

adv

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5

MLD school 06 Copyright: C. Faloutsos, 2006 25

CMU SCS

R-trees

• eg., w/ fanout 4:

A

B

C

DE

FG

H

I

J

P1

P2

P3

P4

P1 P2 P3 P4

F GD E

H I JA B C

adv

MLD school 06 Copyright: C. Faloutsos, 2006 26

CMU SCS

R-trees - range search?

A

B

C

DE

FG

H

I

J

P1

P2

P3

P4

P1 P2 P3 P4

F GD E

H I JA B C

adv

MLD school 06 Copyright: C. Faloutsos, 2006 27

CMU SCS

R-trees - range search?

A

B

C

DE

FG

H

I

J

P1

P2

P3

P4

P1 P2 P3 P4

F GD E

H I JA B C

adv

MLD school 06 Copyright: C. Faloutsos, 2006 28

CMU SCS

Conclusions

• Fast indexing: through GEMINI

– feature extraction and

– (off the shelf) Spatial Access Methods

[Gaede+98]

MLD school 06 Copyright: C. Faloutsos, 2006 29

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

• Features for images (DWT, morphology,

etc)

• Tools and case studies: PCA, ICA, Random

Walks

• Conclusions

MLD school 06 Copyright: C. Faloutsos, 2006 30

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

– DFT, DWT etc

– SVD/PCA

– MDS and FastMap

• ...

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6

MLD school 06 Copyright: C. Faloutsos, 2006 31

CMU SCS

DFT and cousins

• very good for compressing real signals

• more details on DWT: later

MLD school 06 Copyright: C. Faloutsos, 2006 32

CMU SCS

DFT and stocks

0.00

2000.00

4000.00

6000.00

8000.00

10000.00

12000.00

1 11 21 31 41 51 61 71 81 91 101 111 121

Fourier appx actual

• Dow Jones Industrial

index, 6/18/2001-

12/21/2001

MLD school 06 Copyright: C. Faloutsos, 2006 33

CMU SCS

DFT and stocks

0.00

2000.00

4000.00

6000.00

8000.00

10000.00

12000.00

1 11 21 31 41 51 61 71 81 91 101 111 121

Fourier appx actual

• Dow Jones Industrial

index, 6/18/2001-

12/21/2001

• just 3 DFT

coefficients give very

good approximation

1

10

100

1000

10000

100000

1000000

10000000

1 11 21 31 41 51 61 71 81 91 101 111 121

Series1

freq

Log(ampl)

MLD school 06 Copyright: C. Faloutsos, 2006 34

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

– DFT, DWT etc

– SVD/PCA

– MDS and FastMap

• ...

MLD school 06 Copyright: C. Faloutsos, 2006 35

CMU SCS

SVD

• THE optimal method for dimensionality

reduction

– (under the Euclidean metric)

MLD school 06 Copyright: C. Faloutsos, 2006 36

CMU SCS

SVD - Motivation

area

bri

ghtn

ess

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MLD school 06 Copyright: C. Faloutsos, 2006 37

CMU SCS

SVD - Motivation

area

bri

ghtn

ess

MLD school 06 Copyright: C. Faloutsos, 2006 38

CMU SCS

SVD – dim. reduction

• minimum RMS error

SVD: gives

best axis to project

v1

area

bri

ghtn

ess

MLD school 06 Copyright: C. Faloutsos, 2006 39

CMU SCS

Singular Value Decomposition

(SVD)• SVD (~LSI ~ KL ~ PCA ~ spectral

analysis...)

• LSI: S. Dumais; M. Berry

• KL: eg, Duda+Hart

• PCA: eg., Jolliffe

• Details: [Press+], [Faloutsos96]

MLD school 06 Copyright: C. Faloutsos, 2006 40

CMU SCS

SVD

• Extremely useful tool

– (also behind PageRank/google and Kleinberg’s

algorithm for hubs and authorities)

• But may be slow: O(N * M * M) if N>M

• any approximate, faster method?

MLD school 06 Copyright: C. Faloutsos, 2006 41

CMU SCS

SVD shorcuts• random projections (Johnson-Lindenstrauss

thm [Papadimitriou+ pods98])

MLD school 06 Copyright: C. Faloutsos, 2006 42

CMU SCS

Random projections

• pick ‘enough’ random directions (will be

~orthogonal, in high-d!!)

• distances are preserved probabilistically,

within epsilon

• (also, use as a pre-processing step for SVD

[Papadimitriou+ PODS98])

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MLD school 06 Copyright: C. Faloutsos, 2006 43

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

– DFT, DWT etc

– SVD

– MDS and FastMap

• ...

MLD school 06 Copyright: C. Faloutsos, 2006 44

CMU SCS

MDS / FastMap

• but, what if we have NO points to start

with?

(eg. Time-warping distance)

• A: Multi-dimensional Scaling (MDS) ;

FastMap

MLD school 06 Copyright: C. Faloutsos, 2006 45

CMU SCS

MDS/FastMap

01100100100O5

10100100100O4

100100011O3

100100101O2

100100110O1

O5O4O3O2O1~100

~1

~1

MLD school 06 Copyright: C. Faloutsos, 2006 46

CMU SCS

MDS

Multi Dimensional

Scaling

MLD school 06 Copyright: C. Faloutsos, 2006 47

CMU SCS

FastMap

• Multi-dimensional scaling (MDS) can do

that, but in O(N**2) time

• FastMap [Faloutsos+95] takes O(N) time

MLD school 06 Copyright: C. Faloutsos, 2006 48

CMU SCS

FastMap: Application

VideoTrails [Kobla+97]

scene-cut detection (about 10% errors)

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MLD school 06 Copyright: C. Faloutsos, 2006 49

CMU SCS

Conclusions - Practitioner’s

guide

Similarity search in time sequences

1) establish/choose distance (Euclidean, time-

warping,…)

2) extract features (SVD, DWT, MDS), and use

an SAM (R-tree/variant) or a Metric Tree (M-

tree)

2’) for high intrinsic dimensionalities, consider sequential

scan (it might win…)

MLD school 06 Copyright: C. Faloutsos, 2006 50

CMU SCS

Books

• William H. Press, Saul A. Teukolsky, William T.

Vetterling and Brian P. Flannery: Numerical Recipes in C,

Cambridge University Press, 1992, 2nd Edition. (Great

description, intuition and code for SVD)

• C. Faloutsos: Searching Multimedia Databases by Content,

Kluwer Academic Press, 1996 (introduction to SVD, and

GEMINI)

MLD school 06 Copyright: C. Faloutsos, 2006 51

CMU SCS

References

• Agrawal, R., K.-I. Lin, et al. (Sept. 1995). Fast Similarity

Search in the Presence of Noise, Scaling and Translation in

Time-Series Databases. Proc. of VLDB, Zurich,

Switzerland.

• Babu, S. and J. Widom (2001). “Continuous Queries over

Data Streams.” SIGMOD Record 30(3): 109-120.

• Breunig, M. M., H.-P. Kriegel, et al. (2000). LOF:Identifying Density-Based Local Outliers. SIGMOD

Conference, Dallas, TX.• Berry, Michael: http://www.cs.utk.edu/~lsi/

MLD school 06 Copyright: C. Faloutsos, 2006 52

CMU SCS

References

• Ciaccia, P., M. Patella, et al. (1997). M-tree: An Efficient

Access Method for Similarity Search in Metric Spaces.

VLDB.

• Foltz, P. W. and S. T. Dumais (Dec. 1992). “Personalized

Information Delivery: An Analysis of Information

Filtering Methods.” Comm. of ACM (CACM) 35(12): 51-

60.

• Guttman, A. (June 1984). R-Trees: A Dynamic Index

Structure for Spatial Searching. Proc. ACM SIGMOD,

Boston, Mass.

MLD school 06 Copyright: C. Faloutsos, 2006 53

CMU SCS

References

• Gaede, V. and O. Guenther (1998). “Multidimensional

Access Methods.” Computing Surveys 30(2): 170-231.

• Gehrke, J. E., F. Korn, et al. (May 2001). On Computing

Correlated Aggregates Over Continual Data Streams.

ACM Sigmod, Santa Barbara, California.

MLD school 06 Copyright: C. Faloutsos, 2006 54

CMU SCS

References

• Gunopulos, D. and G. Das (2001). Time Series Similarity

Measures and Time Series Indexing. SIGMOD

Conference, Santa Barbara, CA.

• Hatonen, K., M. Klemettinen, et al. (1996). Knowledge

Discovery from Telecommunication Network Alarm

Databases. ICDE, New Orleans, Louisiana.

• Jolliffe, I. T. (1986). Principal Component Analysis,Springer Verlag.

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MLD school 06 Copyright: C. Faloutsos, 2006 55

CMU SCS

References

• Keogh, E. J., K. Chakrabarti, et al. (2001). Locally

Adaptive Dimensionality Reduction for Indexing Large

Time Series Databases. SIGMOD Conference, Santa

Barbara, CA.

• Kobla, V., D. S. Doermann, et al. (Nov. 1997).

VideoTrails: Representing and Visualizing Structure in

Video Sequences. ACM Multimedia 97, Seattle, WA.

MLD school 06 Copyright: C. Faloutsos, 2006 56

CMU SCS

References

• Oppenheim, I. J., A. Jain, et al. (March 2002). A MEMS

Ultrasonic Transducer for Resident Monitoring of Steel

Structures. SPIE Smart Structures Conference SS05, San

Diego.

• Papadimitriou, C. H., P. Raghavan, et al. (1998). Latent

Semantic Indexing: A Probabilistic Analysis. PODS,

Seattle, WA.

• Rabiner, L. and B.-H. Juang (1993). Fundamentals of

Speech Recognition, Prentice Hall.

MLD school 06 Copyright: C. Faloutsos, 2006 57

CMU SCS

References

• Traina, C., A. Traina, et al. (October 2000). Fast feature

selection using the fractal dimension,. XV Brazilian

Symposium on Databases (SBBD), Paraiba, Brazil.

MLD school 06 Copyright: C. Faloutsos, 2006 58

CMU SCS

References• Dennis Shasha and Yunyue Zhu High Performance

Discovery in Time Series: Techniques and Case StudiesSpringer 2004

• Yunyue Zhu, Dennis Shasha ``StatStream: StatisticalMonitoring of Thousands of Data Streams in Real Time'‘VLDB, August, 2002. pp. 358-369.

• Samuel R. Madden, Michael J. Franklin, Joseph M.Hellerstein, and Wei Hong. The Design of an AcquisitionalQuery Processor for Sensor Networks. SIGMOD, June2003, San Diego, CA.

MLD school 06 Copyright: C. Faloutsos, 2006 59

CMU SCS

Outline

• Problem definition and motivation

• Indexing and feature extraction

• Features for images (DWT, morphology,

etc)

• Tools and case studies: PCA, ICA, Random

Walks

• Conclusions

MLD school 06 Copyright: C. Faloutsos, 2006 60

CMU SCS

How to extract features?

• Eg.: [Bob Murphy]: protein localization images

ER

Tubulin DNATfRActin

NucleolinMitoLAMP

gpp130giantin

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MLD school 06 Copyright: C. Faloutsos, 2006 61

CMU SCS

ER

Tubulin DNATfRActin

NucleolinMitoLAMP

gpp130giantin

How to extract features?

• Eg.:

ERERERER

brightness(?)brightness(?)brightness(?)brightness(?)

area(?)area(?)area(?)area(?) MitMitMitMit

MLD school 06 Copyright: C. Faloutsos, 2006 62

CMU SCS

(Natural) image features

[Flickner+, 95] from IBM’s QBIC:

• Color

• Shape

• Texture

MLD school 06 Copyright: C. Faloutsos, 2006 63

CMU SCS

(Natural) image features

[Flickner+, 95] from IBM’s QBIC:

• Color: average R/G/B; color histograms

• Shape

• Texture

MLD school 06 Copyright: C. Faloutsos, 2006 64

CMU SCS

Images - shapes

• distance function: Euclidean, on the area,

perimeter, and 20 ‘moments’ [QBIC, ’95]

• Q: other ‘features’ / distance functions?

MLD school 06 Copyright: C. Faloutsos, 2006 65

CMU SCS

Images - shapes

• (A1: turning angle)

• A2: wavelets

• A3: morphology: dilations/erosions

• ...

MLD school 06 Copyright: C. Faloutsos, 2006 66

CMU SCS

Images - shapes

• (A1: turning angle)

• A2: wavelets

• A3: morphology: dilations/erosions

• ...

angle

length

θ

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MLD school 06 Copyright: C. Faloutsos, 2006 67

CMU SCS

Wavelets - example

http://grail.cs.washington.edu/projects/query/Wavelets achieve *great* compression:

20 100 400 16,000

# coefficients

MLD school 06 Copyright: C. Faloutsos, 2006 68

CMU SCS

Wavelets - intuition

• Edges (horizontal; vertical; diagonal)

MLD school 06 Copyright: C. Faloutsos, 2006 69

CMU SCS

Wavelets - intuition

• Edges (horizontal; vertical; diagonal)

• recurse

MLD school 06 Copyright: C. Faloutsos, 2006 70

CMU SCS

Wavelets - intuition

• Edges (horizontal; vertical; diagonal)

• http://www331.jpl.nasa.gov/public/wave.ht

ml

MLD school 06 Copyright: C. Faloutsos, 2006 71

CMU SCS

Wavelets

• Many wavelet basis:

– Haar

– Daubechies (-4, -6, -20)

– Gabor

– ...

MLD school 06 Copyright: C. Faloutsos, 2006 72

CMU SCS

Gabor Function

We can extend the function to generate

Gabor filters by rotating and dilating

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CMU SCS

Wavelets:

• Extremely useful

• Excellent compression / feature extraction,

for natural images

• fast to compute ( O(N) )

MLD school 06 Copyright: C. Faloutsos, 2006 74

CMU SCS

Crush intro to Haar wavelets

• The simplest to code, explain and

understand

MLD school 06 Copyright: C. Faloutsos, 2006 75

CMU SCS

Wavelets - DWT

• Similarly, DFT suffers on short-duration

waves (eg., baritone, silence, soprano)

time

value

MLD school 06 Copyright: C. Faloutsos, 2006 76

CMU SCS

Haar Wavelets

• subtract sum of left half from right half

• repeat recursively for quarters, eight-ths, ...

MLD school 06 Copyright: C. Faloutsos, 2006 77

CMU SCS

Wavelets - construction

x0 x1 x2 x3 x4 x5 x6 x7

adv

MLD school 06 Copyright: C. Faloutsos, 2006 78

CMU SCS

Wavelets - construction

x0 x1 x2 x3 x4 x5 x6 x7

s1,0

+-

d1,0 s1,1d1,1 .......level 1

adv

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CMU SCS

Wavelets - construction

d2,0

x0 x1 x2 x3 x4 x5 x6 x7

s1,0

+-

d1,0 s1,1d1,1 .......

s2,0level 2

adv

MLD school 06 Copyright: C. Faloutsos, 2006 80

CMU SCS

Wavelets - construction

d2,0

x0 x1 x2 x3 x4 x5 x6 x7

s1,0

+-

d1,0 s1,1d1,1 .......

s2,0

etc ...

adv

MLD school 06 Copyright: C. Faloutsos, 2006 81

CMU SCS

Wavelets - construction

d2,0

x0 x1 x2 x3 x4 x5 x6 x7

s1,0

+-

d1,0 s1,1d1,1 .......

s2,0

Q: map each coefficient

on the time-freq. plane

t

f

adv

MLD school 06 Copyright: C. Faloutsos, 2006 82

CMU SCS

Wavelets - construction

d2,0

x0 x1 x2 x3 x4 x5 x6 x7

s1,0

+-

d1,0 s1,1d1,1 .......

s2,0

Q: map each coefficient

on the time-freq. plane

t

f

adv

MLD school 06 Copyright: C. Faloutsos, 2006 83

CMU SCS

Haar wavelets - code

#!/usr/bin/perl5

# expects a file with numbers

# and prints the dwt transform

# The number of time-ticks should be a power of 2

# USAGE

# haar.pl <fname>

my @vals=();

my @smooth; # the smooth component of the signal

my @diff; # the high-freq. component

# collect the values into the array @val

while(<>){

@vals = ( @vals , split );

}

my $len = scalar(@vals);

my $half = int($len/2);

while($half >= 1 ){

for(my $i=0; $i< $half; $i++){

$diff [$i] = ($vals[2*$i] - $vals[2*$i + 1] )/ sqrt(2);

print "\t", $diff[$i];

$smooth [$i] = ($vals[2*$i] + $vals[2*$i + 1] )/ sqrt(2);

}

print "\n";

@vals = @smooth;

$half = int($half/2);

}

print "\t", $vals[0], "\n" ; # the final, smooth component

adv

MLD school 06 Copyright: C. Faloutsos, 2006 84

CMU SCS

Images - shapes

• (A1: turning angle)

• A2: wavelets

• A3: morphology: dilations/erosions

• ...

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CMU SCS

Other shape features

• Morphology (dilations, erosions, openings,

closings) [Korn+, VLDB96]

shape (B/W) “structuring

element”

R=1

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Other shape features

• Morphology (dilations, erosions, openings,

closings) [Korn+, VLDB96]

shape “structuring

element”

R=0.5

R=1

R=2

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Other shape features

• Morphology (dilations, erosions, openings,

closings) [Korn+, VLDB96]

shape “structuring

element”

R=0.5

R=1

R=2

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Morphology: closing

• fill in small gaps

• very similar to ‘alpha contours’

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Morphology: closing

• fill in small gaps

‘closing’,

with R=1MLD school 06 Copyright: C. Faloutsos, 2006 90

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Morphology: opening

• ‘closing’, for the complement =

• trim small extremities

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Morphology: opening

‘opening’

with R=1

• ‘closing’, for the complement =

• trim small extremities

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Morphology

• Closing: fills in gaps

• Opening: trims extremities

• All wrt a structuring element:

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Morphology

• Features: areas of openings (R=1, 2, …) and

closings

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Morphology

• resulting areas: ‘pattern spectrum’

– translation ( and rotation) independent

• As described: on b/w images

– can be extended to grayscale ones (eg., by

thresholding)

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Conclusions

Features for color, shape, texture

• Shape: wavelets; math. morphology

• texture: wavelets

we didn’t elaborate:

• color: color histograms; avg R/G/B

• and many more

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References

• Faloutsos, C., R. Barber, et al. (July 1994). “Efficient and

Effective Querying by Image Content.” J. of Intelligent

Information Systems 3(3/4): 231-262.

• Faloutsos, C. and K.-I. D. Lin (May 1995). FastMap: A

Fast Algorithm for Indexing, Data-Mining and

Visualization of Traditional and Multimedia Datasets.

Proc. of ACM-SIGMOD, San Jose, CA.

• Faloutsos, C., M. Ranganathan, et al. (May 25-27, 1994).

Fast Subsequence Matching in Time-Series Databases.

Proc. ACM SIGMOD, Minneapolis, MN.

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References

• Christos Faloutsos, Searching Multimedia Databases by

Content, Kluwer 1996

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References

• Flickner, M., H. Sawhney, et al. (Sept. 1995). “Query by

Image and Video Content: The QBIC System.” IEEE

Computer 28(9): 23-32.

• Goldin, D. Q. and P. C. Kanellakis (Sept. 19-22, 1995). On

Similarity Queries for Time-Series Data: Constraint

Specification and Implementation (CP95), Cassis, France.

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References

• Charles E. Jacobs, Adam Finkelstein, and David H. Salesin.

Fast Multiresolution Image Querying SIGGRAPH '95,

pages 277-286. ACM, New York, 1995.

• Flip Korn, Nikolaos Sidiropoulos, Christos Faloutsos, Eliot

Siegel, Zenon Protopapas: Fast Nearest Neighbor Search in

Medical Image Databases. VLDB 1996: 215-226

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Resources - software and urls

• http://www.dsptutor.freeuk.com/jsanalyser/

FFTSpectrumAnalyser.html : Nice java

applets for FFT

• http://www.relisoft.com/freeware/freq.html

voice frequency analyzer (needs

microphone)

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Resources: software and urls

• xwpl: open source wavelet package from

Yale, with excellent GUI

• http://monet.me.ic.ac.uk/people/gavin/java

/waveletDemos.html : wavelets and

scalograms

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Books

• William H. Press, Saul A. Teukolsky, William T.

Vetterling and Brian P. Flannery: Numerical Recipes in C,

Cambridge University Press, 1992, 2nd Edition. (Great

description, intuition and code for DFT, DWT)

• C. Faloutsos: Searching Multimedia Databases by Content,

Kluwer Academic Press, 1996 (introduction to DFT,

DWT)

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Outline

• Problem definition and motivation

• Indexing and feature extraction

• Features for images (DWT, morphology,

etc)

• Tools and case studies: PCA, ICA, Random

Walks

• Conclusions

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ICA

• Independent Component Analysis

– better than PCA/SVD

– also known as ‘blind source separation’

– (the `cocktail discussion’ problem)

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Intuition behind ICA:

perimeter

area

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PCAarea

perimeter

Intuition behind ICA:

MLD school 06 Copyright: C. Faloutsos, 2006 107

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ICAPCA

area

perimeter

Intuition behind ICA:

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Intuition behind ICA:

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PCA finds the hyperplane.

Intuition behind ICA:

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PCA finds the hyperplane. ICA finds the correct patterns.

Dimensionality reduction

Intuition behind ICA:

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ICA in action

• stock prices - find groups / outliers!

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Eg.: Hidden variables in stock prices

Alcoa

American

Express

Boeing

Caterpillar

Citi Group

(Q) What patterns do you see?

DJIA (29 companies)Unimodal data

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Eg.: Hidden variables in stock prices

Alcoa

American Express

Boeing

Caterpillar

Citi Group

Discovery non-obvious hidden variables.(How to do this automatically?)

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Hidden variablesDow Jones Industrial Average

Alcoa

American

Express

Boeing

Caterpillar

Goal:

Find meaningful

hidden variables

Time tick (week)

Weekly DJIA closing prices (01/02/1990-08/05/2002)

n=660 data points, m=29 companies

Data point

adv

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(A1) How did stock prices change?

AA1, …, XOM1

AAn, …, XOMn

H11, H12, …, H1m

Hn1, Hn2, …, Hnm

=

B11, B12, …, B1m

Bm1, Bm2, …, Bmm? ?

Time tickHidden variable

Time tick

Math

29

n=660

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Hidden variables by AutoSplit

Hidden v#1 (meaning??)

Caterpillar Intel

Hidden v#2 (meaning??)

0.940.63 0.03

0.64B1,CAT

B1,INTC B2,CAT

B2,INTC

More…

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Hidden variables by AutoSplit

“General trend” “Internet bubble”

0.940.63 0.03

0.64B1,CAT

B1,INTC B2,CAT

B2,INTC

More…

Caterpillar Intel

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Making the most of

ICA/AutoSplit

• Pattern discovery (hidden variables)

• Clusters (tech vs non-tech stocks)

• Outlier detection

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Companies related to hidden

variable 1

0.658768Hewlett-Packard0.900317Du Pont

0.647774Home Depot0.903858Coca Cola

0.638010Intel0.906542MMM

0.624570WalMart0.911120Boeing

0.021885AT&T0.938512Caterpillar

LowestHighest

B1,j

Hidden variable 1 : “General trend”

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Outlier detection

AT&T

UnitedTechnologies

Walmart

ExxonMobil

“General trend”

Outlier

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Conclusions for ICA

• Better than PCA

• Actually, uses PCA as a first step!

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References

• Fukunaga, K. (1990). Introduction to Statistical

Pattern Recognition, Academic Press.

• Jolliffe, I. T. (1986). Principal Component

Analysis, Springer Verlag.

• Aapo Hyvarinen, Juha Karhunen, and Erkki Oja

Independent Component Analysis, John Wiley &

Sons, 2001.

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References

• Jia-Yu Pan, Hiroyuki Kitagawa, Christos

Faloutsos, and Masafumi Hamamoto. AutoSplit:

Fast and Scalable Discovery of Hidden Variables

in Stream and Multimedia Databases. PAKDD

2004

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Outline

• ...

• Tools and case studies: PCA, ICA, Random

Walks

– ICA; case study: visual vocabulary (ViVo)

– Random Walks

• Conclusions

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ViVo: cat retina mining

• with Ambuj Singh, Mark Verardo, Vebjorn

Ljosa, Arnab Bhattacharya (UCSB)

• Jia-Yu Tim Pan, HJ Yang (CMU)

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Retina, its image, and the detachment

• retina

Layers of tissues

stained by 3

antibodies

(R,G,B)

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Computer Scientist’s View of

Retinal Detachment

normal detachment 7 days after

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Detachment Development

Normal1 day after detachment

3 days after detachment

7 days after detachment

28 days after detachment

3 months after detachment

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Data and Problem

• (Problem) What happens in retina after

detachment?

– What tissues (regions) are involved?

– How do they change over time?

• How will a program convey this info?

• More than classification

“we want to learn what classifier learned”

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Visual vocabulary?news:

president,

minister,

economic

sports:

baseball,

score,

penalty

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Visual Vocabulary (ViVo)

generation

Step 1:

Tile image

Step 2:

Extract tile

features

Step 3:

ViVo

generation

Visual

vocabulary

V1

V2

Feature 1

Fea

ture

2

8x12 tiles

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Biological interpretation

V11

V8

V10

V1

ID

Co-occurring processes: Müller cellhypertrophy and rod opsin redistribution

Redistribution of rod opsin into cellbodies of rod photoreceptors

Healthy outer segments of rod

photoreceptors

GFAP in inner retina (Müller cells)

Description ConditionViVo

Detached

Detached

Healthy

Healthy

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Which tissue is significant on 7-day?

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Automatic ViVo-annotation of

images

• A tile represents a ViVo vk

if the largest coefficient of

the tile is along the kth basis

vector

• A ViVo vk represents a

class ci if the majority of its

tiles are in that class

• For each image, the

representative ViVos for the

class are automatically

highlighted

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Conclusion

• ICA can help us find ``good’’ hidden

variables (= visual vocabulary words)

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Outline

• ...

• Tools and case studies: PCA, ICA, Random

Walks

– ICA

– image captioning - Random Walks

• Conclusions

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Image captioning:

correlation between images and

terms

“sea”, “sun”, “sky”, “water”

“cat”, “forest”, “grass”, “tiger”

“?”, “?”, “?”, “?”

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Idea

• each modality into a set of nodes

• (could have many more modalities: audio,

motion, etc etc)

• random walk, on the resulting m-partite

graph

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Image captioning: extract regions

“sea”, “sun”, “sky”, “water”

“cat”, “forest”, “grass”, “tiger”

“?”, “?”, “?”, “?”

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Mixed-Media Graph

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

From training images Image to caption

region

image

term

Object-Attribute-Value(OAV) links

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Mixed-Media Graph

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

From training images Image to caption

region

image

term

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Mixed-Media GraphNearest Neighbor

(NN) links

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

From training images Image to caption

region

image

term

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Random Walk with Restart (at

t=0)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

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Random Walk with Restart (at

t=1)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

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Random Walk with Restart (at

t=2)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

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Random Walk with Restart (at

t=3)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

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Random Walk with Restart (at

t=0)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

Blue step: restart at the query node (with probability c)Red step: randomly walk among one link (with prob. 1-c)

Query/Restart node

(1-c)/2 (1-c)/2

c

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Random Walk with Restart (at

t>0)

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

Blue step: restart at the query node (with probability c)Red step: randomly walk among one link (with prob. 1-c)

Query/Restart node

(1-c)/3 (1-c)/3

c(1-c)/3

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Steady state probability of RWR

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term Query/Restart node

Dark green: higher probability to be visited

Light green: lower probability to be visited

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Steady state probability of RWR

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term Query/Restart node

Dark green: higher probability to be visited

Light green: lower probability to be visited

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Compute the steady state

probability

yprobabilitrestart :

matrix transition:

ctorrestart ve :

yprobabilit statesteady :

))1((

)1(1

c

cc

cc

A

v

u

vAIu

vuAu

v

v

vv

vvv

−−−=⇒

+−=

Math

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Putting MMG+RWR to work

• Tasks:

– Image captioning: GCap [Pan+, MDDE 2004]

– ( Multi-modal retrieval: MMSS [Pan+, ICDM

2004] )

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GCap: MMG+RWR for image

captioning

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

Image to caption

region

image

term

Query/Restart nodegrasscat tigerPredicted caption:

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Examples of captioning results

tree, water,

building, sky

lion, grass, cat, manegrass, cat, tiger,

waterOur

caption

sun, water,

tree, sky

mane, cat, lion, grasscat, grass, tiger,

waterTruth

Image

Predicted terms are listed in the order of likeliness.

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Extension: other cross-modal

queries

• e.g., text-to-text

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5 t6 t7 t8

….

….

….

….

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(Extension) Other cross-modal

queries

• For example, the term-to-term correlation

– “Given a term, find other similar terms.”

prototypeTurnBuildingsStreetTracksCar

BoatsStoneSkyArchWaterBridge

HawkNestOwlNightBirdsBranch

54321Term

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Extension: group captioning

r1 r2 r3 r4 r5 r6 r7 r8 r9 ….

i1 i2 ij

t1

ri ri+1

itest

….

….

t2 t3 t4 t5

….

….

….

….

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(Extension) Captioning images in

groups

sky, water, tree, sunGroup

caption

sky, sunwater, tree, people,

sky

tree, people, sky,

water

GCap

caption

sun, watersun, clouds, sky,

horizon

sun, water, tree,

skyTruth

Image

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Summary

• GCap = MMG+RWR, for image captioning

– Easy to apply to all kinds of cross-modal data

– Outperforms the best previous image captioning

results

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OVERALL CONCLUSIONS

Powerful tools for image/multimedia mining:

• GEMINI + R-trees for similarity search

• Feature extraction with

– Wavelets,

– PCA, ICA

• Cross-modal mining / auto-captioning:

– graph-based methods + Random Walks

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christos <at> cs.cmu.edu

www.cs.cmu.edu/~christos