Research Group of Prof. Dr. C. Sminchisescu
Mathematical Sciences



Computer Vision (MA-INF 2201)

Summer Semester 2010

Times: Monday & Wednesday: 9 - 11am (lectures); Thursday: 8:15 - 10 am (exercises)

Place: rooms A207 (lectures), and A7a (exercises), both in Romerstr. 164

 


Syllabus (please check regularly for course materials and updates!)

  • No classes during the week of May 24th-28th (Pentecost Break)

  • To access course materials, get password in class or send email to:

           tutors.inf2201.10 at gmail.com (provide your student ID)

  • Assignments or exams can be turned-in/taken in English or in German

 

      Week

Subject

 Readings

 Assignments

 

 

 1

 

 

 

 

Apr.12th: Introduction   

Course logistics: pre-requisites, resources, programming and exercises.

 

   

 

Apr.14th: Overview of computer vision, problems and challenges 

Introduction. An overview of what can we do today with computer vision. Typical vision sub-problems. Why is vision hard? Challenges and open issues.

Slides: 2 per page. 4 per page.

 

Szeliski, Ch. 1  
 

 

 2

 

 

 

 

Apr.19th: Image representation and filtering

Image representation. Perception and spatial scale. Linear filtering, correlation and  convolution operators. Noise and the calculation of image gradients. Edge preserving (bilateral) filtering.

Slides: 2 per page. 4 per page.

 

Szeliski, Ch. 3.1., 3.2

Forsyth and Ponce, Ch. 7.1,7.2, 8.1, 8.2

 

 

Apr.21st: Edge detection   

Edge detection. Laplacian operators. Sampling and aliasing. Fourier analysis. Image pyramids.

Slides: 2 per page. 4 per page.

 

Forsyth and Ponce, Ch. 7, 8

 Receive Assignment 1
 

 

3

 

 

 

 

Apr. 26th: Interest point detectors   

Pyramid blending. Image feature detectors. Auto-correlation functions and mathematical analysis for the Förstner-Harris operator. Scale-invariant extensions.

Slides: 2 per page. 4 per page.

 

Szeliski, Ch. 4.1  
 

Apr.28th: Descriptors and matching   

Affine-invariant interest point operators. SIFT and Shape Context feature descriptors. Distinctiveness and repeatability.  Constrained global image correspondence problems. Linear assignment and the Hungarian algorithm.

Slides: 2 per page. 4 per page.

 

Szeliski, Ch. 4 Receive Assignment 2
 

 

4

 

 

 

May 3rd: Projective geometry for computer vision   

Projective plane, projective transformations and projective invariants. Line and point duality. Relation between projective, affine and euclidean transformations. Applications of cross-ratio.

Slides: 2 per page. 4 per page.

 

J. Mundy and A. Zisserman: Projective Geometry for Machine Vision (pdf), Sec 23.1 - 23.5

Hartley and Zisserman, Ch. 2.1 - 2.4, 3.1-3.2.2

 

 

May 5rth: Geometric Constraints and the Fundamental Matrix   

Camera models. Computation of homographies and camera matrices from point correspondeces. Epipolar geometry and the fundamental matrix. Algebraic and statistical methods. Estimation and normalization.

Slides: 2 per page. 4 per page.

 

Hartley and Zisserman, Ch. 9.1 - 9.5 Epipolar Geometry and the Fundamental Matrix (pdf draft). Turn-in Assignment 1.
Receive Assignment 3
 

 

5

 

 

 

May 10th: Stereo   

The essential matrix. Orthographic factorization methods. Rectification. Disparity-based representations, the cyclopean eye and coherency-based stereo. Stereo constraints. Plane sweeping methods.

Slides: 2 per page. 4 per page.

 

Szeliski Ch. 7.3, 11.1 - 11.5  

 

May 12th: Optical Flow   

Image warping. The motion field and the optical flow. Brightness constancy equations and first order approximations. Translational (Lucas-Kanade) optical flow. Affine flow. Hierarchical estimation methods. Layered models.

Slides: 2 per page. 4 per page.

 

Szeliski Ch. 8.1 (without 8.1.2), 8.2 (up to 8.2.1), 8.4 (up to 8.4.1) and 8.5. (no seminar this Thursday)
 

 

6

 

 

 

May 17th: Lighting and color

Color constancy and the physics of light. Radiometry, BRDF models. Low-dimensional models for color spectra. Color matching and Grassman's laws. Measuring color by color matching.

Slides: 2 per page. 4 per page.

 

Forsyth and Ponce, Ch. 6  

 

May 19th:    

No lecture, "Dies Academicus".

 

  May 20th
Turn-in Assignment 2.
Receive Assignment 4
 

 

7

 

 

 

May 31st: Image segmentation I. Modeling and clustering

Visual grouping and Gestalt principles. Image segmentation as a clustering problem. Agglomerative and divisive methods, K-means and mean shift. Spectral graph partitioning methods.

Slides: 2 per page. 4 per page.

 

Forsyth and Ponce, Ch. 14 Solution for Assignment 2 available.

 

Jun 2nd: Image segmentation II. Contours and snakes   

Hough transform. Contour segmentation methods. Snakes and live-wire. Discrete and continuous formulations. Elasticity and stiffness priors. Gradient flow and dynamic programming solvers.

Slides: 2 per page. 4 per page.

 

  June 3rd
(no seminar this Thursday)
 

 

8

 

 

 

Jun 7th: Machine learning for computer vision   

The role of machine learning in computer vision. Hypothesis spaces, generalization and overfitting. Generative and discriminative models.  Dependencies on graphs, conditional and marginal parameterziations. d-separation and the Bayes ball algorithm.

Slides: 2 per page. 4 per page.

 

Bishop, Ch. 8.1 - 8.3  

 

Jun 9th: Support Vector Machines   

The bias-variance decomposition. Linear maximum margin classifiers. Primal and dual formulations. Support Vector Machines. Feature spaces and kernels. Mercer's condition and kernel closure rules. Kernelizing algorithms.

Slides: 2 per page. 4 per page.

 

C. Burges: A tutorial on Support Vector Machines, Kluwer, 1998 (pdf) June 10th
Turn-in Assignment 3.
Receive Assignment 5
Solution for Assignment 1 available.
 

 

9

 

 

 

Jun 14th: Learning for object recognition I

Introduction to object recognition. Eigenfaces: face recognition using Principal Component Analysis (PCA). K-means and bag-of-feature models.

Slides: 2 per page. 4 per page.

 

Szeliski, Ch. 14.2, 14.4
Solution for Assignment 3 available.

 

Jun 16th: Learning for object recognition II

Processing pipeling in the visual cortex. Hierarchical feature extraction architectures, based on template matching and max-pooling operations: HMAX by Riesenhuber and Poggio '99, extensions by Mutch and Lowe '08.

Slides: 2 per page. 4 per page.

 

Riesenhuber and Poggio: Hierarchical models of object recognition in cortex, 1999 (pdf)
 

Mutch and Lowe: Object class recognition and localization using sparse features with limited receptive fields, 2008 (pdf)

June 17th
Turn-in Assignment 4. Solution for Assignment 4.

Assignment 5: helper function to draw a descriptor.

Receive Assignment 6
 

 

 

10

 

 

 

Jun 21st: Boosting and sliding window methods for object detection   

Ensemble classifiers and meta-learning frameworks. Bagging, stacking and boosting. Functional gradient descent. Adaboost and sliding-window methods for object detection.

Slides: 2 per page. 4 per page.

 

   

 

Jun 23rd:   

Branch and bound optimization for efficient image search.

Slides: 2 per page. 4 per page.

 

 
 

 

11

 

 

 

Jun 28th: Learning in fully observed statistical models 

Regression. Feature selection methods, shrinkage and the lasso. Bayesian classifiers and linear discriminant analysis. Naive Bayes.

Slides: 2 per page. 4 per page.

 

  June 30th
Turn-in Assignment 5.

 

Jun 30th: Latent variable models and the EM algorithm

Learning in partially observed models. Mixture of experts. Complete and incomplete log-likelihoods. Free energy and view of EM as bound optimization. Illustration for Gaussian mixture fitting.

Slides: 2 per page. 4 per page.

 

Bishop, Ch. 9 July 1st
Turn-in Assignment 6.
Receive Assignment 7


July 2nd
Solution for Assignment 5 available (drawing function)
 

 

12

 

 

 

Jul 5th: Dimensionality reduction and continuous latent variable models     

Linear (PCA) and non-linear dimensionality reduction methods (ISOMAP, Laplacian Eigenmaps). Factor Analysis and Probabilistic PCA. Spectral latent variable models. Applications to visual inference (object tracking, 3d reconstruction).

Slides: 2 per page. 4 per page.

 

   

 

Jul 7th: Belief Propagation     

Elimination methods. Moralization and triangulation. Belief propagation in tree-structured models. Hidden Markov Models.

Slides: 2 per page. 4 per page.

 

Bishop, Ch. 8.4
Solution for Assignment 6 available (drawing function).
 

 

13

 

 

 

Jul 12th: Learning random fields.

Log linear models and maximum entropy.

Slides: 2 per page. 4 per page.

 

   

 

Jul 14th: Reconstruction of 3D articulated objects.

Levels of 3D modeling. State space priors and observation models. Generative vs. discriminative models. Particle filters.

Slides: 2 per page. 4 per page.

  July 19th
Turn-in Assignment 7.
 

 

14

 

 

 

July 19th: Optimization and sampling methods.

High-dimensional visual inference. Local maxima and transition states. High-dimensional sampling strategies (hyperdynamics, hypersurface sweeping).

Slides: 2 per page. 4 per page.

 

 
Solution for Assignment 7 available

 

July 21st: Exam