GREC 2003 : 31 July 2003

FRE 2645

Local Structural Analysis: Local Structural Analysis:

a Primera Primer

Mathieu Delalandre¹ , Eric Trupin¹, Jean-Marc Ogier²

¹PSI Laboratory, Rouen University, France

²L3I Laboratory, La Rochelle University, France

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PlanPlan

Introduction General Decomposition Method Comparison Method Combination Conclusion

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PlanPlan

Introduction General Decomposition Method Comparison Method Combination Conclusion

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Introduction Introduction

shape recognition process statistical analysis and recognition (Jain 2000) structural analysis and recognition (Tombre 1996)

feature extractionor ‘analysis’

(Loncarnic 1998)recognition

A

B

D

C

3175.03.12

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IntroductionIntroduction

structural recognition graph-matching approach (Hancock 2002) grammar approach (Blostein 1995)

structural analysis

localglobal

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PlanPlan

Introduction General Decomposition Method Comparison Method Combination Conclusion

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General DecompositionGeneral Decomposition

four steps:

object graph extraction

mathematical approximation

A

B

D

C

high level objectconstruction

object graph correction

A

B

D

C

A

B

D

C

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General DecompositionGeneral Decomposition

step 1, object graph extraction (1)

skeletonisation contouring

meshesregion

runtracking

segmented object

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General DecompositionGeneral Decomposition

step 1, object graph extraction (2) skeletonisation based methods, two steps:

skeletonisation (Lam 1995) skeleton graph extraction (Tombre 1999)(Lau 2002)

contouring based methods morphological based methods (Hasan 2000) following based methods (Ablameyko & Pridmore 2000)

tracking based methods, two tracking types: line tracking (Song 2002) junction tracking (Ogier 1992)

skeletonisation

contouring

tracking

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General DecompositionGeneral Decomposition

step 1, object graph extraction (3) run decomposition based methods

vertical and horizontal run graph (Burge 1998)

region decomposition based methods orientation map (Cao 2000) and wave aggregation (Delalandre 2003)

run region

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General DecompositionGeneral Decomposition

step 1, object graph extraction (4) meshes based methods, two steps (vaxivière 1995):

image is splited up into meshes meshes are recognized according to a library

segmented based methods, two segmentations: line, circle and ellipsis segmentation (Matas 1999) (Su 2002) junction segmentation (Chen 2000)

meshes segmented object

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General DecompositionGeneral Decomposition

step 2, mathematical approximation vector, circle, and curve fitting (Rosin 1995)

step 3, high level object construction circle reconstruction (Hilaire 2001) contour matching (Zou 2000) (Ramel 2000)

mathematical approximation

circle reconstruction

contour matching

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General DecompositionGeneral Decomposition

step 4, object graph correction, some examples: pruning merging (Delalandre 2003) junction fusion (Lin 2002) vectorial correction (Hilaire 2001)

junction fusionpruning & merging vectorial correction

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PlanPlan

Introduction General Decomposition Method Comparison Method Combination Conclusion

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Method ComparisonMethod Comparison

object graph extraction, seven criteria:

morphology

junction

invariance

sensitivity

semantic

reversibility

complexity

best method

tracking, run, region

run, region

skeletonisation, contouring

object segmentation

meshes, tracking, object segmentationregion, run

tracking, meshes

Criterion Junction: junction detection Morphology: various shape analysis Invariance: scale and orientation change Sensitivity: noise resistance Semantic: low or high level object Reversibility: image return Complexity: low algorithmic complexity

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PlanPlan

Introduction General Decomposition Method Comparison Method Combination Conclusion

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Method CombinationMethod Combination

Analysis

Analysis

Recognition 1

Recognition 2

comparison

comparison combination different analysis and recognition, then comparison

multi representation

skeletonisation and contouring (Nakajima 1999)

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Method CombinationMethod Combination

hybrid combination different analysis, then hybrid graph construction and

recognition multi representation

run and skeleton graph (Xue 2001) region graph and statistical description (Delalandre 2003)

Analysis orRecognition

Analysis orRecognition

RecognitionHybrid construction

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Method CombinationMethod Combination

cooperative combination first analysis in order to help the second analysis

process simplification

object simplification (Song 2002)

Analysis or Recognition Analysis Recognition

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PlanPlan

Introduction Global Structural Analysis Local Structural Analysis Method Combination Conclusion

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ConclusionConclusion

local structural analysis: connected component graph 4 main steps 7 criteria of comparison

method combination: a research perspective

multi representation (structural and statistical-structural) process simplification