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Prof. Bernard Mérialdo

EURECOM

Journées du LABRI - 17 Juin 2011

Multimedia Indexing Multimedia Indexing

Outline Outline

Introduction

TRECVID Video Indexing Benchmarks

Video and MM Summarization

Evaluation (BLEU, ROUGE, VERT)

Conclusions

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EURECOM.fr EURECOM.fr

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eurocom.com Eurocom Corporation -

Number 1 in Desktop Replacement Notebook

eurocom.fr EUROCOM BROADCAST

produits audio- professionnels pour la radio

eurocom.co.uk EUROCOM ENTERTAINMENT

SOFTWARE euro-com.fr

Euro'com - Vente d'électroménager à prix réduits eurocom-systemes.fr

systèmes téléphoniques

eurecom.com matériel de stockage d'occasion

eurecom.fr ou eurecom.edu Graduate school and research center

in communications systems

EURECOM EURECOM

Higher education and Research GIE

Subsidiary of Institut Télécom

Academic members (5 european universities) Industrial members (10 international companies)

International:

80 Master students (15+ nationalities) 70 PhD students (20+ nationalities) 23 professors (11 nationalities)

Research activity:

3 departments: mobile, multimedia, security 96 research contracts, 4,6M€

200 publications / year

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Multimedia Indexing Multimedia Indexing Information Overload:

40 G web pages

>5G pictures

>15M videos

Audio-visual data:

Sound and speech recognition Natural Language Processing Video Analysis

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TRECVID Evaluation TRECVID Evaluation

International Evaluation Benchmark

Organized by NIST since 2001 Schedule:

Data is distributed to participants

Participants run their algorithms, send results to NIST NIST evaluates

Results are compared during workshop

Several tasks:

Semantic Indexing Topic Search Copy Detection Event Detection

Summarization (2006-2008)

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(4)

TRECVID in

TRECVID in numbers numbers

Year Hours of video (training/test)

Type

2001 11 NIST videos

2002 73 Internet Open Archive

2003 66/67 TV News (ABC, CNN, CSPAN)

2004 130/70 TV News (ABC, CNN, CSPAN)

2005 85/85 TV News (+arabic, chinese)

2006 170/158 TV News (+arabic, chinese)

50 BBC Rushes

2007 50/50 Sound and Vision (dutch)

18/17 BBC Rushes

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2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

12 17 24 33 41 54 54 77 63 73 110

Participants:

Video data:

TRECVID

TRECVID Video Video Data Data

Year Hours of video (training/test)

Type

2008 100/100 Sound and Vision (dutch)

35/18 BBC Rushes

200 Surveillance (Gatwick airport) 2009 100/280 Sound and Vision (dutch)

53/20 BBC Rushes

150 Surveillance (Gatwick airport)

2010 200/200 Internet Archive

180 Sound and Vision

45 Surveillance (Gatwick airport)

50 BBC Rushes

100 HAVIC

2011 400/200 Internet Archive

150 Surveillance (Gatwick airport)

50 BBC Rushes

100 HAVIC

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TRECVID 2011

TRECVID 2011 Tasks Tasks

Known-item search task (automatic, manual, interactive) Search for a known video from text description

0001 KEY VISUAL CUES: man, clutter, headphone

QUERY: Find the video of bald, shirtless man showing pictures of his home full of clutter and wearing headphone

0002 KEY VISUAL CUES: Sega advertisement, tanks, walking weapons, Hounds

QUERY: Find the video of an Sega video game advertisement that shows tanks and futuristic walking weapons called Hounds.

0003 KEY VISUAL CUES: Two girls, pink T shirt, blue T shirt, swirling lights background

QUERY: Find the video of one girl in a pink T shirt and another in a blue T shirt doing an Easter skit with swirling lights in the background.

0004 KEY VISUAL CUES: George W. Bush, man, kitchen table, glasses, Canada

QUERY: Find the video about the cost of drugs, featuring a man in glasses at a kitchen table, a video of Bush, and a sign saying Canada.

0005 KEY VISUAL CUES: village, thatch huts, girls in white shirts, woman in red shorts, man with black hair

QUERY: Find the video of a Asian family visiting a village of thatch roof huts showing two girls with white shirts and a woman in red shorts entering several huts with a man with black hair doing the commentary.

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TRECVID 2011 Tasks TRECVID 2011 Tasks

Known-item search task :

Automatic:

Manual:

Interactive:

10 10

Query Human query System Result

Query Human query System Result

Query System Result

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TRECVID 2011

TRECVID 2011 Tasks Tasks

Content-based multimedia copy detection

Find transformed copies of a video segment

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TRECVID 2011

TRECVID 2011 Tasks Tasks

Event detection in airport surveillance video

PersonRuns, Pointing, CellToEar, ObjectPut, Embrace, PeopleMeet, PeopleSplitUp

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TRECVID 2011

TRECVID 2011 Tasks Tasks

Instance search (interactive, automatic)

Searching a visual occurrence of a target given a few examples ( for example logo detection, product and landmark recognition)

Person Object Location

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TRECVID 2011

TRECVID 2011 Tasks Tasks

Semantic indexing (SIN)

Find shots containing a given semantic concept (previously called « High Level Feature Detection »

Objective: build generic concept detectors

Method:

Assume concept presence is binary (contained or not) System ranks shots by confidence score of presence Best 2000 shots are returned for each feature

Manual assessment by NIST (yes/no for each shot) Compute Mean Average Precision (MAP)

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TRECVID

TRECVID Semantic Semantic Concepts Concepts

2002 2003 2004 2005 2006 2007 2008 2009

outdoors indoors face people cityscape landscape text overlay speech instrumental

sound monologue

outdoors news subject

face people building road vegetation animal female speech car/truck/bus aircraft news subject

monologue non studio

setting sporting event weather news zoomin physical

violence Madeleine Albright

boats / ships Madeleine

Albright Bill Clinton trains or

railroad cars beach basket score airplane

taking off people

walking or running physical

violence road

people walking /running explosion or

fire map US flag building

exterior waterscape/

waterfront mountain prisoner sports

sports weather office meeting desert mountain Waterscape

/waterfront corporate

leader police security military

personnel animal computer tv

screen us flag airplane car truck people

marching explosion fire maps charts

sports weather office meeting desert mountain waterscape/w

aterfront police

security military

personnel animal computer tv

screen us flag airplane car truck boat/ship people

marching explosion fire maps charts

classroom bridge emergency

vehicle dog kitchen airplane flying two people bus driver cityscape harbor telephone street demonstration

or protest hand mountain nighttime boat ship flower singing

classroom chair infant traffic intersection doorway airplane flying person playing a

musical instrument bus person playing

soccer cityscape person riding a

bicycle telephone person eating demonstration or

protest hand people dancing nighttime boat ship female human face

closeup singing

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TRECVID

TRECVID Semantic Semantic Concepts Concepts

2010: 130 concepts (+ ontology relations)

2011: 500 concepts (+ ontology relations)

Development data is manually annotated

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Development Data Test Data

200 hours 200 hours

130 Kshots 130 Kshots

Development Data Test Data

400 hours 200 hours

260 Kshots 130 Kshots

(9)

TRECVID Concept Annotation TRECVID Concept Annotation

Collaborative Annotation Active Learning

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TRECVID Concept Annotation TRECVID Concept Annotation Generic Concept Detector

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Feature Extraction

Supervised Classification Training

Feature

Extraction Classifier Testing

P(X=Airplane) Training Data

Airplane Airplane Not Airplane

(10)

Image/

Image/Video Video Features Features

Global:

Color Histogram

Wavelets, Gabor filters, Edges + spatial arrangements

Local:

SIFT, SURF

Motion:

Optical flow, activity

Audio/Text:

MFCC, speech/music/noise Keywords from metadata or ASR

Specific:

Face detection Video-OCR

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Local features: Bag Of Words Local features: Bag Of Words

Bag-Of-Words histogram

20 20

(Columbia U)

(11)

Supervised

Supervised Classifiers Classifiers

Classifiers:

SVM Support Vector Machines K-NN Nearest Neighbours NN Neural Networks Boosting

Ensemble

Fusion:

Different features / classifiers for a concept Classifiers for different concepts

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GDR

GDR--ISIS IRIM Action ISIS IRIM Action

Coordinated action LIG/MRIM, ETIS, LIF, LISTIC, LABRI, LIF, GIPSA, EURECOM

LIG/hNdN : normalized RGB Histogram LIG/gabN : normalized Gabor transform LIG/opp_sift_har : bag of word, opponent sift ETIS/global_X: histogram, quaternionic wavelets LISTIC_Stip_X : nb of Spatio-Temporal Interest Points LaBRI/faces : OpenCV+median temporal filtering LaBRI/residualMotion_nPX : residual motion vectors LIF/percepts : mid-level concepts on several grid blocks GIPSA/AudioSpectro : spectral profile

GIPSA/AudioHamonicity

EUR/EUR-sm462 : Salency color moments

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TRECVID Generic Architecture TRECVID Generic Architecture

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Video Data

Feature 1 Feature 2 Feature 3

Feature N

Classifier 1 Classifier 2 Classifier 3

Classifier N

Fusion

Cross-concept correlation

For each concept

TRECVID 2010 SIN Performance TRECVID 2010 SIN Performance

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TRECVID SIN

TRECVID SIN Task Task

Conclusions on SIN task:

System performance improve

More data or better model ?

Cross-domain models are to be improved

How to quickly adapt to a new domain ?

Computation requirements are increasing

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Multimedia Summarization Multimedia Summarization

Overload of Multimedia information, specially videos

Lots of TV channels Lots of recording devices

Summarization is a useful tool:

Quickly grasp the main content Decide to watch entire video or not Allows to quickly compare several videos Sometimes find relevant information

Specific problems:

Multi-Media Multi-Video Evaluation

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Video Summarization Video Summarization

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Select important instants

Extract and assemble

Static keyframes Dynamic VideoSkim

Video Summarization is difficult Video Summarization is difficult

Efficient selection requires:

Analysis Modeling

“Understanding”

Evaluation of importance

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Select important instants

(15)

Video Summarization is easy Video Summarization is easy

Lots of possible approaches for selection

From random choice To numerical optimization

How to prove that a summary is good (or bad)?

A major problem is Evaluation

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Video Summary Evaluation Video Summary Evaluation

Many proposals, two basic approaches:

Objective metrics (quantitative)

SVD over feature frame matrix [Gong 2000]

Shot Reconstruction Degree [Liu 2004]

Shot importance [Uchihashi 1999]

User studies (qualitative)

Keyframe Counting [Dufaux 2000]

User satisfaction [Ngo 2003]

Content identification [Smith 1998, Lu 2004]

Dilema: automatic vs realistic

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TRECVID BBC Rushes summarization task TRECVID BBC Rushes summarization task

Rushes from BBC archive

Unedited material from dramatic series

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* http://www-nlpir.nist.gov/projects/trecvid/

Rushes Video Structure Rushes Video Structure A rushes video contains:

Junk frames

Test bar patterns

Junk recordings, irrelevant shots

Scenes

Recordings of a prepared action A scene contains several takes

Each take is a tentative recording for the action A take generally starts with a clapboard

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Scene 1 Scene 2

Junk Take 1 Take 2 Take 3 Junk Take 1 Take 2

(17)

Rushes Video Structure Rushes Video Structure

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Several takes of the same scene

TRECVID BBC Rushes summarization task TRECVID BBC Rushes summarization task 2006: organize, no evaluation

2007: summarize, evaluate

List of topics and events built for ground truth 4% summary is built for each video

Evaluator watches summary and counts topics present

2008: summarize, evaluate

2% summary is built for each video

Evaluator watches summary and counts topics present

2009: discontinued

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Summarization Evaluation Summarization Evaluation

Ground truth : human annotation of visible topics Sample for MRS044500 :

2 men in dark suits walk past Ford truck to building entrance 2 men in dark suits enter building

person in brown coat opens rear end car and removes wheelchair (seen from front of car)

woman walks around car to passenger window (seen from rear end of car) close up of man in passenger seat (seen from front of car)

woman in brown coat removes wheelchair and brings it round to the passenger door (seen from front of car)

man in beige suit appears (seen from front of car) man in beige suit opens car door (seen from front of car)

woman in brown jacket undoes man in car's seatbelt (seen from front of car)

woman in brown jacket helps passenger into wheelchair (seen from front of car)

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Summarization Evaluation Summarization Evaluation

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Video

Clay vase and bowl hang on wall Pile of jugs Close up of larger clay bowl and two smaller ones

Clay objects on floor; standing vertically in corner by window Two men walk out from doorway; exit left Clay vessels of various sizes on wooden benches

Closeup of clay vessels with handles at left end of shelf

Pan right from clay vessels with handles Camera looks up and down to view pots on both sides of wooden fence Clay pot with grass hanging out of it Four women (full view) dance in a circle Camera tilts down to legs (knees down) of women dancing

Summary

Ground Truth

Randomly Selected Topics

Assessors

Bearded man (shoulders up) in helmet; takes off helmet; talks;

exits left

Man (shoulders up) holds clay pot talks; exits left Clay vase and bowl hang on wall Four clay pitchers

Camera pans right to stack of three clay bowls and another beside on shelf

Closeup of stack of 3 bowls and half another View of just one vase hanging on wall Pile of jugs

Clay vessel with pointed bottom, hanging from spike on wall Close up of pointed bottom of vase Camera scans up from pointed bottom of vessel to spike on wall

Bowls, rock?, and other clay objects on table; shelf behind Two shelves with clay objects Camera looks down from 2 shelves to clay objects on table Close up of larger clay bowl and two smaller ones Camera pans right, viewing two shelves with clay pots Clay objects on floor; standing vertically in corner by window Camera zooms in on clay objects stacked in corner by window Camera looks up from floor viewing stacked clay vessels Doorway to house with stone walls and pots outside Two men walk out from doorway; exit left Close up of 2 clay vessels (one orange, one grey) on wooden shelf

Camera pans left past clay vessels on wooden shelf Clay vessels of various sizes on wooden benches Camera zooms in on small caly vessels with handles and spouts

Closeup of small clay vessels (no handles) at left end of shelf Closeup of clay vessels with handles at left end of shelf Pan right from clay vessels with handles Close up bowl on pedestal Closeup of bowl with sun/flower design in middle Zoom out from bowl on pedestal Clay pots on both sides of wooden fence;

Camera looks up and down to view pots on both sides of wooden fence

Clay pot with grass hanging out of it Four women (full view) dance in a circle

Y/N Y/N

Y/N

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EURECOM 2008 Summarization system EURECOM 2008 Summarization system

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COST 292

COST 292 Summarization Summarization System System Based on Spectral Clustering

LABRI contribution: mid-level features:

Face

Camera movement

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Second smallest eigenvector used in clustering and scene detection process

0,018 0,028 0,038 0,048 0,058 0,068 0,078

1 6 11 16 21 26 31 36 41 46 51 56 61 66 71 76 81 86 91 96 101 106 111 116 121 126 131 136 141 146 time

Cluster 1

Cluster 2

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TRECVID Summarization Evaluation TRECVID Summarization Evaluation

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0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9

ATTLabs.1_DU ATTLabs.2_DU BU_FHG.1_DU Brno.1_DU CMU.1_DU CMU.2_DU COST292.1_DU DCU.1_DU DCU.2_DU ETIS.1_DU EURECOM.1_DU FXPAL.1_DU FXPAL.2_DU GMRV-… GTI-UAM.1_DU GTI-UAM.2_DU IRIM.1_DU IRIM.2_DU JRS.1_DU JRS.2_DU K-Space.1_DU K-Space.2_DU NHKSTRL.1_DU NII.1_DU NII.2_DU PicSOM.1_DU PolyU.1_DU QUT_GP.1_DU REGIM.1_DU Sheffield.1_DU TokyoTech.1_DU UEC.1_DU UG.1_DU UPMC-… VIREO.1_DU VIVA-… VIVA-… asahikasei.1_DU cmubase3.1_DU ipan_uoi.1_DU nttlab.1_DU thu-intel.1_DU thu-intel.2_DU

Fraction of inclusions

Internet Multi

Internet Multi--Video Summarization Video Summarization

Collaboration with wikio.fr

News aggregator Collect news

information from various sites Categorize/gather Contains text, video

Objective:

Multimedia summaries of multi-documents articles

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(21)

Summarization Evaluation Summarization Evaluation

Problem:

No ground truth

No perfect summary

Different people will create different summaries Different people will generally agree on summary

ranking

Solution:

Same problem appeared in:

Machine translation → BLEU evaluation Text summarization → ROUGE evaluation Idea: compare candidate with a set of references

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Machine Translation Evaluation Machine Translation Evaluation

Machine Translation BLEU [Papineni 2002]

“BiLingual Evaluation Understudy”

N-gram precision based metric:

Used in NIST evaluations

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∑ ∑

∑ ∑

∈ ∈

∈ ∈

=

Candidates

C n-gram C

Candidates

C n-gram C clip

n count n-gram

n-gram count

BLEU ( )

)

( Value clipped

with reference

value

(22)

Text Summarization Evaluation Text Summarization Evaluation

ROUGE [Lin 2004]

“Recall- Oriented Understudy for Gisting Evaluation”

N-gram recall based metric

Cand: pulse series may ease schizophrenic voices

Ref1: magnetic pulse series sent through brain may ease imaginary schizophrenic sounds

Ref2: yale finds magnetic stimulation pulses may provide some relief to schizophrenic voices

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{ }

{ }

∑ ∑

∑ ∑

∈ ∈

∈ ∈

=

References

S n-gram S

References

S n-gram S match

n count n-gram

n-gram count

ROUGE

) (

) (

Summarization Evaluation Summarization Evaluation

VERT [Eurecom 2010]

“Video Excerpt Relevance Threshold”

Recall based measure

Compares candidate keyframes with reference summaries

wC and wS: weight of gramn

Weight = keyframe rank in selection

Several variants explored

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{ }

{ }

∑ ∑

∑ ∑

∈ ∈

∈ ∈

=

Summaries eference

R

S gram S S n

Summaries eference R

S gram S C n

n

n n

gram w

gram w

VERT ( )

)

(

(23)

Summarization Evaluation Summarization Evaluation

First Experiments:

Keyframe automatic selection

User keyframe selection and ranking

→ Reference summaries

Statistical comparison

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VERT Evaluation VERT Evaluation

On going experiment:

Large scale experimentation on Wikio laboratory site 30 groups of 6 videos each, for each group, selection of

(max) 60 keyframes For each user:

Ask for keyframe selection and ranking – Reference summaries R(u,v) – Used to compute VERT Ask for summary evaluation

– By pair

– Used to evaluate VERT

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Conclusions Conclusions

MM Indexing is a hard problem

Evaluation is required to measure progress Machine Learning is effective

But

Comparative benchmarks tend to limit innovation

Is more data better than smarter models ? Which are the right criteria for evaluation ?

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Thank you Merci

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