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Image Processing and Analysis: Applications and Trends
João Manuel R. S. Tavares
[email protected] www.fe.up.pt/~tavares
AES ATEMA’ 2010 (Le Quebec, CANADA) Int. ConferenceMontreal & Quebec City, CANADA
June 27 to July 03 , 2010on
Advances and Trends in Engineering Materialsand their Applications
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Outline
1. Introduction
2. Segmentation
3. Motion Tracking
4. Analysis of Objects: Matching, Registration and Morphing
5. 3D Reconstruction
6. Conclusions
7. Research Team
2Image Processing and Analysis: Applications and TrendsJoão Manuel R. S. Tavares
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Introduction
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• The researchers of Computational Vision aim the development of algorithms to perform in fully or semi-automatically manner operations and tasks carry out by the (quite complex) human’s vision system
4Image Processing and Analysis: Applications and Trends
Original images
Azevedo et al. (2010), Three-dimensional reconstruction and characterization of human external shapes from two-dimensional images using volumetric methods, Computer Methods in Biomechanics and Biomedical Engineering 13(3): 359-369
Computational 3D model built voxelized and poligonized
Introduction
João Manuel R. S. Tavares
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• Image processing and analysis are topics of the most importance for our Society
• Algorithms of image processing and analysis are frequently used, for example, in:
– Medicine– Biology– Industry– Natural Sciences– Engineering
• Examples of common tasks involving algorithms of image processing and analysis are:
– noise removal– geometric correction– segmentation, recognition (2D-4D)– motion tracking and analysis, including matching, registration and morphing (2D-4D)– 3D reconstruction
5Image Processing and Analysis: Applications and Trends
Introduction
João Manuel R. S. Tavares
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Introduction: Usual Computational Pipeline for Image Processing and Analysis
Image Processing and Analysis: Applications and Trends 6
Image(s) enhancement
Image(s) segmentation / features extraction
tracking
matching
morphing
Image(s)
motionanalysis registration
image processing
image analysis /computational
visionJoão Manuel R. S. Tavares
3D vision
computer vision
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Segmentation
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Segmentation• It is intended to identify in a full or semi- automatic manner
objects (2D/3D) presented in static images or in image sequences
• The most usual methodologies are based on template matching, statistical, geometric or physical modeling, or neuronal networks
• It is one of the most usual operations involved in the computational analysis of objects from images, and very often it is the first “important” step of image processing and analysis
• Frequent problems: noise, low resolution, reduce contrast, shapes not previously known, occlusion, multiple objects, etc.
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 8
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Segmentation• Example: segmentation of contours in dynamic
pedobarography (Otsu method, morphologic operators)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 9
Original images After segmentation
Bastos & Tavares (2004), Improvement of Modal Matching Image Objects in Dynamic Pedobarography using Optimization Techniques, Lecture Notes in Computer Science 3179:39-50
camera mirror
contact layer + glass
reflected light glass
pressure opaque layer
lamp
lamp transparent layer
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Segmentation• Example: analysis of damage in composite materials
(binarization and region analysis)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 10
Original image After segmentation
Damage areaMeasures obtained
Marques et al. (2009), Delamination Analysis of Carbon Fibre Reinforced Laminates: Evaluation of a Special Step Drill , Composites Science and Technology, 69(14): 2376-2382
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Segmentation• Example: hardness evaluation from indentation images
(Johannsen and Bille threshold, region growing)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 11
Vickers hardness Brinell hadnessFilho et al. (2010), Brinell and Vickers Hardness Measurement using Image Processing and Analysis Techniques, Journal of Testing and Evaluation 38(1):88-94
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Segmentation• Example: analysis of material microstructures (neuronal
network)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 12
Original images After segmentationAlbuquerque et al. (2008), A New Solution for Automatic Microstructures Analysis from Images Based on a Backpropagation Artificial Neural Network, Nondestructive Testing and Evaluation 23(4):273-283
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Segmentation• Example: evaluation of nickel alloy secondary phases from
Scanning Electron Microscopic images (neuronal network)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 13
Original image Image segmented
Albuquerque et al. (2010), Automatic Evaluation of Nickel Alloy Secondary Phases from SEM Images, Microscopy Research and Technique, doi: 10.1002/jemt.20870 (in press)
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Segmentation• Example: evaluation on synthetic material porosity from
optical microscopic images (neuronal network)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 14
Original images withtraining pixels
Image segmented
Albuquerque et al. (2010), New computational solution to quantify synthetic material porosity from optical microscopic images, Journal of Microscopy, doi: 10.1111/j.1365-2818.2010.03384.x (in press)
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Segmentation• Example: control of a servomechanism by
gesture recognition (orientation histograms)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 15
Tavares et al. (2005), Control a 2-Axis Servomechanism by Gesture Recognition using a GenericWebCam, International Journal of Advanced Robotic Systems 2(1):39-44
Running mode
Conversion for 256 gray levels
Orders orientation histogram vectors
initialization (stored in memory)
1 2 3 4
Orders images acquisition (one by one)
Command image
acquisition Conversion for 256
gray levels
Comparison of the images orientation histogram vector
with the stored vectors of the preset orders images
Associated command
order
1 3 4
1 2 4
1 2 3
2 3 4
4
2
1
Learning mode
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Segmentation• Example: detection of breast tumours from mammography
images (Hough transform)
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Chagas et al. (2007), An Application of Hough Transform to Identify Breast Cancer in Images, VIPimage 2007, 363-368
Original image After segmentation
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Segmentation• Example: object recognition (image template matching)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 17
Carvalho & Tavares (2005), Metodologias para identificação de faces em imagens: Introdução e exemplos de resultados, CMNI 2005
×fft fft
ift
( )3ift D CC( )2ift D CC
max CC
Original imageTemplate image
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Segmentation• Example: segmentation of facial features
(deformable geometric template)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 18
Carvalho & Tavares (2006), Two Methodologies for Iris Detection and Location in Face Images, CompIMAGE 2006, 129-134Carvalho & Tavares (2007), Eye detection using a deformable template in static images, VipIMAGE 2007, 209-215
Original image and associated energy fields
Segmentation of the iris using adeformable template (a circle)
Segmentation of an eye using an
deformable template
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Segmentation• Example: segmentation of skin regions in images (statistical
model)
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Skin samples used to build the statistical model Original image and
segmentation obtained
Carvalho & Tavares (2005), Metodologias para identificação de faces em imagens: Introdução e exemplos de resultados, CMNI 2005
Probably functionused
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Segmentation• Example: segmentation of scene background/foreground in
image sequences (statistical models)
Backgroundsubtraction
Foreground objectdetection
Vasconcelos & Tavares (2008), Image Segmentation for Human Motion Analysis: Methods and Applications, WCCM8 / ECCOMAS 2008
Original images
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Segmentation• Example: segmentation of faces and hands in images
(Active Shape Model)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 21
Segmentations achieved (initial, intermediate and final steps)Vasconcelos & Tavares (2008), Methods to Automatically Built Point Distribution Models for Objects like Hand Palms and Faces Represented in Images, Computer Modeling in Engineering & Sciences 36(3):213-241
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Segmentation• Example: segmentation of faces in images (Active Appearance
Model)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 22
Vasconcelos & Tavares (2008), Methods to Automatically Built Point Distribution Models for Objects like Hand Palms and Faces Represented in Images, Computer Modeling in Engineering & Sciences 36(3):213-241
Segmentations achieved (initial, intermediate and final steps)
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Segmentation• Example: analysis of the vocal tract shape during speech
production from MRI (Active Shape Models)
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Vasconcelos et al. (2010), Towards the Automatic Study of the Vocal Tract from Magnetic Resonance Images, Journal of Voice, doi:10.1016/j.jvoice.2010.05.002 (in press)
Intermediate segmentation II
Originalimage
Finalsegmentation
Intermediate segmentation I
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Segmentation• Example: analysis of the vocal tract shape during speech
production from MRI (Active Appearance Models)
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Vasconcelos et al. (2010), Towards the Automatic Study of the Vocal Tract from Magnetic Resonance Images, Journal of Voice, doi:10.1016/j.jvoice.2010.05.002 (in press)
Intermediate segmentations
Initialsegmentation
Finalsegmentation
Intermediate segmentations
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Segmentation• Example: segmentation of medical images (active contours -
snakes)
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Original image andinitial contour
Final contour
Tavares et al. (2009), Computer Analysis of Objects’ Movement in Image Sequences: Methods and Applications, International Journal for Computational Vision and Biomechanics 2(2): 209-220
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Segmentation• Example: segmentation of objects in images (deformable
contour, FEM, Lagrange equation)
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Original images and initial contours Final contoursGonçalves et al. (2008), Segmentation and Simulation of Objects Represented in Images using Physical Principles, Computer Modeling in Engineering & Sciences 32(1):45-55
rubberk = 200N/m14s
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Segmentation• Example: segmentation of medical images (level-set method)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 27
Original image Initial segmentation Final segmentation
Perdigão et al. (2005), Geração de modelos de malhas de elementos finitos a partir de imagens médicas 2D, Encontro_1_Biomecânica, 81-85
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Segmentation• Example: segmentation of pelvic floor from MRI (level-set
method, prior knowledge, shape influence field)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 28
Ma et al. (2010), A shape guided C-V model to segment the levator ani muscle in axial magnetic resonance images, Medical Engineering & Physics, doi:10.1016/j.medengphy.2010.05.002 (in press)
Pelvic floor segmented
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Segmentation• Example: new computational framework for medical image
segmentation (VC++, OpenCV, ITK)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 29
Interface of our platform
Ma et al. (2008), Segmentation of Structures in Medical Images: Review and a New Computational Framework, CMBBE2008
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Segmentation• Example: segmentation of organs from female pelvic cavity
MRI (using our platform)
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Ma et al. (2010), A Review of Algorithms for Medical Image Segmentation and their Applications to the Female Pelvic Cavity, Computer Methods in Biomechanics and Biomedical Engineering 13(2):235-246
Region Growing Watershed
Malladi’s methodGeodesic Active Contour
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Motion Tracking
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Motion Tracking• It is intended to track the motion (and/or the deformation) of
objects along image sequences• In this area, the methodologies based on optical flow, block
matching and stochastic methods are widespread• Usually, it concerns the estimation of the motion involved,
the management of the features being tracked, and the analysis of the motion tracked as well as its quantification
• Usual problems: non-rigid motions, geometric distortions, non-constant illumination, occlusions, noise, multiple objects, etc.
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 32
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Motion Tracking• Computational framework to
track features in image sequences(Kalman Filter or Unscented KalmanFilter, optimization, Mahalanobisdistance, management model)
Image Processing and Analysis: Applications and Trends 33
Pinho & Tavares (2009), Tracking Features in Image Sequences with Kalman Filtering, Global Optimization, Mahalanobis Distance and a Management Model, Computer Modeling in Engineering & Sciences 46(1):51-75
Pinho & Tavares (2009), Comparison between Kalman and Unscented Kalman Filters in Tracking Applications of Computational Vision, VipIMAGE 2009
João Manuel R. S. Tavares
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Motion Tracking • Kalman Filter
– Optimal recursive Bayesian stochastic method– One of its drawbacks is the restrictive assumption of Gaussian
posterior density functions at every time step• Many tracking problems involve non-linear motions (i.e. human gait)
Image Processing and Analysis: Applications and Trends 34João Manuel R. S. Tavares
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Motion Tracking• Example: tracking marks in gait analysis (Kalman filter,
Mahalanobis distance, optimization, management model)
Image Processing and Analysis: Applications and Trends 35
Prediction Uncertainty Area Measurement Correspondence Result
Pinho et al. (2005), Human Movement Tracking and Analysis with Kalman Filtering and Global Optimization Techniques, ICCB 2005, 915-926Pinho & Tavares (2009), Tracking Features in Image Sequences with Kalman Filtering, Global Optimization, Mahalanobis Distance and a Management Model, Computer Modeling in Engineering & Sciences 46(1):51-75
(5 frames)
João Manuel R. S. Tavares
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36Image Processing and Analysis: Applications and Trends
Pinho et al. (2007), Efficient Approximation of the Mahalanobis Distance for Tracking with the Kalman Filter, International Journal of Simulation Modelling 6(2):84-92
(547 frames)
Pinho et al. (2005), A Movement Tracking Management Model with Kalman Filtering, Global Optimization Techniques and Mahalanobis Distance, LSCCS, Vol. 4A:463-466
Motion Tracking• Example: tracking mice in long image sequences (Kalman
filter, Mahalanobis distance, optimization, management model)
João Manuel R. S. Tavares
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Motion Tracking• Unscented Kalman Filter
– A set of sigma-points from the distribution of the state vector is propagated through the true non-linearity, and the parameters of the Gaussian approximation are then re-estimated
– Addresses the main shortcomings of Kalman Filter, as well as of Extended Kalman Filter, and is more suitable for non-linear motions
Image Processing and Analysis: Applications and Trends 37João Manuel R. S. Tavares
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Motion Tracking• Example: tracking the centre of a square that is moving
according to a non-linear model (Kalman Filter (KF) and Unscented Kalman Filter (UKF))
Image Processing and Analysis: Applications and Trends 38
Motion equations:
0 0
22( 1) 12.51 ,12.51
with 6, 10
x x ii iy xi i
x y
= + − +−= + −
= =
#6
+ predictionsx measurementsx corrections
Kalman Filter results:
João Manuel R. S. Tavares
(8 frames)
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Motion Tracking• Example: tracking the centre of a square that is moving
according to a non-linear model (Kalman Filter (KF) and Unscented Kalman Filter (UKF)) – cont.
Image Processing and Analysis: Applications and Trends 39João Manuel R. S. Tavares
Motion equations:
0 0
22( 1) 12.51 ,12.51
with 6, 10
x x ii iy xi i
x y
= + − +−= + −
= =
(8 frames)
Tracking error (predicted/real state)
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Image Processing and Analysis: Applications and Trends 40
Motion Tracking• Example: tracking the motion of three mice in a real image
sequence (Kalman Filter (KF) and Unscented Kalman Filter (UKF))
+ predictionsx measurementsx corrections
(22 frames)
João Manuel R. S. Tavares
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Image Processing and Analysis: Applications and Trends 41
Motion Tracking• Example: tracking the motion of three mice in a real image
sequence (Kalman Filter (KF) and Unscented Kalman Filter (UKF)) –cont.
Kalman Filter results Unscented Kalman Filter results
João Manuel R. S. Tavares
(22 frames)
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Image Processing and Analysis: Applications and Trends 42
Motion Tracking• Example: tracking the motion of three mice in a real image
sequence (Kalman Filter (KF) and Unscented Kalman Filter (UKF)) –cont.
João Manuel R. S. Tavares
(22 frames)Tracking error (predicted/real state)
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Motion Tracking• Influence of the adopted filter: Kalman Filter (KF) and
Unscented Kalman Filter (UKF)– If the motion is highly nonlinear, then UKF justifies its superior
computational load– Otherwise, KF with the undertaken matching (association)
methodology can accomplish efficiently the tracking– Hence, the decision between KF or UKF is application-dependent
• Frequently, UKF gets superior results• However, when the computational load is somewhat constrained, KF
with a suitable matching strategy can be a good tracking solution
Image Processing and Analysis: Applications and Trends 43João Manuel R. S. Tavares
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Analysis of Objects:Matching, Registration and
Morphing
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Analysis of Objects• Matching
– It is regularly used in the computational analysis of objects from images, for example, to register (i.e. align) objects, recognize objects, attain 3D information, analyze the motion tracked, and so forth
– Generally, it is achieved by considering invariant objects’ characteristics, as curvature, or displacements in a global space (like in modal space)
– Common problems: occlusion, non-rigid deformations, high shape variations, etc.
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 45
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Analysis of Objects• Registration
– It is commonly required in order to compare objects in images acquired at different time instants or according to distinct conditions
– It is essential, for example, in Medicine to follow up the evaluation of patients’ diseases from images
– Usually, it is achieved by considering objects’ characteristic features, as points of maximum curvature, and their matching followed by the estimation of the involved transformation
– Common problems: key and invariant features not easily identified, occlusion, non-rigid deformations, severe shape variations, etc.
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 46
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Analysis of Objects• Morphing (i.e. simulation)
– It is an especially used in Computer Graphics, but also very useful in the analysis of objects from images, for example, to estimate the deformation involved between two objects or between two configurations of an object, to simulate the transitions between two shapes acquired under a high temporal gap, etc.
– Normally, it is attained by considering simple geometric transformations
– However, when it must be considered the real behavior of the objects, physical methodologies and modeling as, for example, FEM, should be considered
• Common difficulties are related with the estimation of the involved forces and with the properties of the adopted (virtual) material
• The adequate matching of the objects is crucial
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 47
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Matching• Using physical or geometrical modeling and modal matching
Image Processing and Analysis: Applications and Trends 48
Modeling(physical or geometrical)
Eigenvalues / eigenvectors computation
Matching matrix
assembly
Contour 1
Contour 2
Matches achievement(optimization)
Modeling(physical or geometrical)
Eigenvalues / eigenvectors computation
Bastos & Tavares (2006), Matching of Objects Nodal Points Improvement using Optimization, Inverse Problems in Science and Engineering 14(5):529-541
João Manuel R. S. Tavares
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• Example: matching contours in dynamic pedobarography (FEM, modal matching, optimization)
Matching
Image Processing and Analysis: Applications and Trends 49
Original images Matched contours
Bastos & Tavares (2004), Improvement of Modal Matching Image Objects in Dynamic Pedobarography using Optimization Techniques, Lecture Notes in Computer Science 3179:39-50
camera mirror
contact layer + glass
reflected light glass
pressure opaque layer
lamp
lamp transparent layer
Tavares & Bastos (2010), Improvement of Modal Matching Image Objects in Dynamic Pedobarography using Optimization Techniques, Progress in Computer Vision and Image Analysis, Chapter 19, 339-368
João Manuel R. S. Tavares
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Matching• Example: matching contours and surfaces in dynamic
pedobarography (FEM, modal analysis, optimization)
Image Processing and Analysis: Applications and Trends 50
Image of dynamic pedobarography
Tavares & Bastos (2005), Improvement of Modal Matching Image Objects in Dynamic Pedobarography using Optimization Techniques, Electronic Letters on Computer Vision and Image Analysis 5(3):1-20
Matching foundbetween two contours
Matching found between two intensity (pressure) surfaces (2 views)
Matching found between iso-contours (2 views)
João Manuel R. S. Tavares
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Registration• Registration of contours in images (geometrical modeling,
optimization, dynamic programming)
Image Processing and Analysis: Applications and Trends 51
Oliveira & Tavares (2008), Algorithm of dynamic programming for optimization of the global matching between two contours defined by ordered points, Computer Modeling in Engineering & Sciences 31(11):1-11
João Manuel R. S. Tavares
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Registration• Example: registration of contours in images (geometrical
modeling, optimization, dynamic programming)
Image Processing and Analysis: Applications and Trends 52
Original images and contours
Matched contours before registration
Matched contours after registration
Oliveira & Tavares (2009), Matching Contours in Images through the use of Curvature, Distance to Centroidand Global Optimization with Order-Preserving Constraint, Computer Modeling in Engineering & Sciences 43(1):91-110
João Manuel R. S. Tavares
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Registration• Example: registration of images in pedobarography
(geometrical modeling, optimization, dynamic programming)
Image Processing and Analysis: Applications and Trends 53
Original images and contours Contours and images before and after registration
Oliveira et al. (2009), Rapid pedobarographic image registration based on contour curvature and optimization, Journal of Biomechanics 42(15):2620-2623João Manuel R. S. Tavares
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Registration• Example: registration of images in pedobarography (Fourier
transform)
Image Processing and Analysis: Applications and Trends 54
Original images Images before andafter registration
Oliveira et al. 2010, Registration of pedobarographic image data in the frequency domain, Computer Methods in Biomechanics and Biomedical Engineering (in press)
João Manuel R. S. Tavares
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Registration• Example: registration of images in pedobarography (Hybrid
method: Contours registration or Fourier transform based registration + Optimization of a Similarity Measure – MSE, MI or XOR)
Image Processing and Analysis: Applications and Trends 55
Original images Images before andafter registration
Oliveira & Tavares 2010, Novel Framework for Registration of Pedobarographic Image Data, Medical & Biological Engineering & Computing (submitted)
João Manuel R. S. Tavares
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Registration• Registration of image sequences in dynamic
pedobarography (spatial and temporal registration)
Image Processing and Analysis: Applications and Trends 56João Manuel R. S. Tavares
Oliveira & Tavares 2010, Spatio-temporal Registration of Pedobarographic Image Sequences, Journal of Biomechanics (submitted)
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Registration• Example: registration of image sequences in dynamic
pedobarography (spatial and temporal registration)
Image Processing and Analysis: Applications and Trends
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João Manuel R. S. Tavares
Original sequencesbefore registration
Preprocessed sequences
Original image sequences
Sequencesafter registration
57
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Morphing
Image Processing and Analysis: Applications and Trends 58
• Physical morphing/simulation of contours in images (FEM, modal analysis, optimization, Lagrange equation)
João Manuel R. S. Tavares
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• Example: morphing contours in images (FEM, modal analysis, optimization, Lagrange equation)
Matching found
Deformations estimated
Morphing
Image Processing and Analysis: Applications and Trends 59
Gonçalves et al. (2008), Segmentation and Simulation of Objects Represented in Images using Physical Principles, Computer Modeling in Engineering & Sciences 32(1):45-55
Original images
João Manuel R. S. Tavares
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3D Reconstruction
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3D Reconstruction• It is intended to achieve the 3D reconstruction of objects or
scenes from images• In this area, the following methodologies are common:
external shapes – active techniques (with energy projection or relative motion), passive techniques (without energy projection nor relative motion) and of space carving; inner shapes – 2D segmentation (contours, for example) and data interpolation
• Usually, it involves tasks of camera calibration, data segmentation, matching, triangulation and interpolation
• Common problems: geometric distortions, bad or unstable illumination, occlusion, noise, multiple objects, complex shapes and topologies, etc.
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 61
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3D Reconstruction• Example: 3D reconstruction of organs from medical images
(segmentation 2D, marching cubes, Delaunay)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 62
Segmentation done in a 2D slice and the 3D reconstruction
obtained
3D reconstruction of some structures of an arm
Perdigão et al. (2005), Sobre a Geração de Malhas Tridimensionais para fins Computacionais a partir de Imagens Médicas, CMNI 2005
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3D Reconstruction• Example: 3D reconstruction of organs from medical images
(segmentation 2D, loft, smooth, Delaunay)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 63
Segmentation donein a 2D slice
Pelvic floorreconstructed
Reconstructed organs from a pelvic
cavityPimenta et al. (2006), Reconstruction of 3D Models from Medical Images: Application to Female Pelvic Organs, CompIMAGE 2006, 343-348Alexandre et al. (2007), 3D reconstruction of pelvic floor for numerical simulation purpose, VipIMAGE2007, 359-362
slices
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3D Reconstruction• Example: 3D reconstruction of a scene using a technique
of active vision (dense stereo vision)
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 64
Disparity mapobtained
Original image pair
Azevedo et al. (2006), Development of a Computer Platform for Object 3D Reconstruction using Active Vision Techniques, VISAPP 2006, 383-388
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3D Reconstruction• Example: 3D reconstruction of objects by space carving
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 65
Azevedo et al. (2008), 3D Object Reconstruction from Uncalibrated Images using an Off-the-Shelf Camera, Advances in Computational Vision and Medical Image Processing: Methods and Applications, 117-136
Original images Computational 3D model built voxelizedand poligonized
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3D Reconstruction• Example: 3D reconstruction of objects by space carving
João Manuel R. S. Tavares Image Processing and Analysis: Applications and Trends 66
Original images Computational 3D model built voxelizedand poligonized
Azevedo et al. (2010), Three-dimensional reconstruction and characterization of human external shapes from two-dimensional images using volumetric methods, Computer Methods in Biomechanics and Biomedical Engineering 13(3): 359-369
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Conclusions
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Conclusions
• The area of image processing and analysis is very complex and demand, but of raised importance in many domains
• Numerous hard challenges exist, as for example, adverse conditions in the image acquisition process, occlusion, objects with complicate shapes, with topological variations or undergoing complex motions
• Considerable work has already been developed, but important and complex goals still to be reached
• Methods and methodologies of other research areas, as of Mathematics, Computational Mechanics, Medicine and Biology, can contribute significantly for their reaching
• For that, collaborations are welcome
68Image Processing and Analysis: Applications and TrendsJoão Manuel R. S. Tavares
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Research Team(Computational Vision)
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Research Team (Computational Vision)
• PhD students (15):– In course: Raquel Pinho, Patrícia Gonçalves, Maria
Vasconcelos, Ilda Reis, Teresa Azevedo, Daniel Moura, Zhen Ma, Elza Chagas, Victor Albuquerque, Francisco Oliveira, Eduardo Ribeiro, António Gomes, João Nunes, Alex Araujo, Sandra Rua
• MSc students (13):– In course: Carlos Faria, Elisa Barroso, Ana Jesus, Veronica
Marques, Diogo Faria– Finished: Daniela Sousa, Francisco Oliveira, Teresa Azevedo,
Maria Vasconcelos, Raquel Pinho, Luísa Bastos, CândidaCoelho, Jorge Gonçalves
• BSc students (2)– Finished: Ricardo Ferreira, Soraia Pimenta
70Image Processing and Analysis: Applications and TrendsJoão Manuel R. S. Tavares
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Image Processing and Analysis:Applications and Trends
João Manuel R. S. Tavares
[email protected] www.fe.up.pt/~tavares
Slide Number 1OutlineIntroductionIntroductionIntroductionIntroduction: Usual Computational Pipeline for Image Processing and Analysis�SegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationSegmentationMotion TrackingMotion TrackingMotion TrackingMotion Tracking Motion TrackingMotion TrackingMotion TrackingMotion TrackingMotion TrackingMotion TrackingMotion TrackingMotion TrackingMotion TrackingAnalysis of Objects:�Matching, Registration and MorphingAnalysis of ObjectsAnalysis of ObjectsAnalysis of ObjectsMatchingMatchingMatchingRegistrationRegistrationRegistrationRegistrationRegistrationRegistrationRegistrationMorphingMorphing3D Reconstruction3D Reconstruction3D Reconstruction3D Reconstruction3D Reconstruction3D Reconstruction3D ReconstructionConclusionsConclusionsResearch Team�(Computational Vision)Research Team (Computational Vision)Slide Number 71