Graph Cuts and Normalized Cuts

Size: px
Start display at page:

Download "Graph Cuts and Normalized Cuts"

Transcription

1 Definition: University of Alicante (Spain) Matrix Computing (subject 3168 Degree in Maths) 30 hours (theory)) + 15 hours (practical assignment)

2 Contents 1. Graph Partitiond, Cuts and Normalization 1. Graph partition 2. Cut and Normalized Cut. What is the optimal partition? 3. The purpose of normalization 4. Properties of the Optimal Partition 2. Problem Formulation (binary) 1. NCut and Laplacian 2. Relaxation to real values. Friedler vector analysis 3. Extenstion: recursive sub-division 3. Application to point and image clustering 1. Point clustering 2. Clustering in images

3 Graph Partitions, Cuts and Normalization Objective,cuts and normalized cuts: Find two disjoint partitions A and B of the vertices V of a graph, so that A B = V and A B =. What is a good partition? Define a precise criterion Given a similaritymeasure w(i,j) between two vertices (e.g. identity when they are connected) a cutvalue(anditsnormalizedversion) is defined as: Optimal bi-partition: Is the oneminimizing the cut value. There are an exponential number of partitions. Can we solve the problem efficiently? Use spectral graph theory!

4 Graph Partitions, Cuts and Normalization Example #7: A1=(1,2,,9), B1 =(10,11,12) cut(a1,b1) = 1 (link between 2 and 10) A2=(1,2,4,,12), B2 =(3) cut(a1,b1) = 1 (link between 3 and 1) asso(a1,v) = 9, asso(b1,v) = 4 Ncut(A1,B1)=1/9 +1/4 =13/36=0.36 asso(a2,v) = 12, asso(b2,v) = 1 Ncut (A2,B2)= 1/12 +1/1 =13/12=1.08 NCut considers the total edge weight connecting a partition with the rest of vertices in the graph, and thus isolated vertices as partitions are avoided!

5 Graph Partitions, Cuts and Normalization Example #2: A1=(1,2,,9), B1 =(10,11,12) cut(a1,b1) = 1 (link between 2 and 10) asso(a1,v) = 9, asso(b1,v) = 4 asso(a1,a1) = 8, asso(b1,b1)=3 Nasso(A1,B1)=8/9+ 3/4 = = 1.63 A2=(1,2,4,,12), B2 =(3) cut(a2,b2) = 1 (link between 3 and 1) asso(a2,v) = 12, asso(b2,v) = 1 asso(a2,a2) = 11, asso(b2,b2) = 0 Nasso(A2,B2) = 11/12 + 0/1 =0.91

6 Graph Partitions, Cuts and Normalization Properties of the optimal partition: Considering NCut we seek theminimization of disassociation between the groups A and B and themaximization of the association within each group: Exercise #5 (proof) Nasso is encoding the association within the group, that is, the ratio between how many weight remains inside and goes outside for both groups.

7 Problem formulation (binary) Using dimensional indicators: [Shi & Malik,00] Given a partition of V in sets A and B. letxa N= V indicatorvector so that x i =1 if node i is in A and x i =-1 if node i is in B. Let Then

8 Problem formulation (binary) Going towards the Laplacian: [Shi & Malik,00] BeingDthe degree matrix andwthe attribute matrix: Definingy We have

9 Problem formulation (binary) Solving the eigensystem: [Shi & Malik,00] If y is relaxed to take real values the latter minimization by solving the following generalized eigenvalue system: But we have to consider the constrainty T D1=0 and relaxing +1-1 to real values: Therefore, the Friedler vector (second vector of the eigensystem) is the solution (close to 1 in cluster A, close to -1 in cluster B) What happens with close to zero values

10 Applications: Graphs W=I Example #2:

11 Applications: Segmentation Example #7: X(red)=(1,0,0) X(blue)=(0,0,1) Waa = Wgg=Wbb=e -0 =1; Wxy x~=y Wxy = e -sqrt(2) =

12 Applications: Segmentation Example #8: X(red)=(1,0,0) X(blue)=(0,0,1) X(black)=(0,0,0) Waa = Wgg=Wbb=e -0 =1; Wrb=Wbr= e -sqrt(2) = Wrblack = Wblackr = e -1 = Wbblack = Wblackb = e-1 =

13 Applications: Segmentation Example #9: X(red)=(1,0,0) X(green)=(0,1,0) X(blue)=(0,0,1) Waa = Wgg=Wbb=e -0 =1; Wxy x~=y Wxy = e -sqrt(2) =

14 Applications: Clustering Example #10: W clustering result

CS 534: Computer Vision Segmentation II Graph Cuts and Image Segmentation

CS 534: Computer Vision Segmentation II Graph Cuts and Image Segmentation CS 534: Computer Vision Segmentation II Graph Cuts and Image Segmentation Spring 2005 Ahmed Elgammal Dept of Computer Science CS 534 Segmentation II - 1 Outlines What is Graph cuts Graph-based clustering

More information

Administration. Final Exam: Next Tuesday, 12/6 12:30, in class. HW 7: Due on Thursday 12/1. Final Projects:

Administration. Final Exam: Next Tuesday, 12/6 12:30, in class. HW 7: Due on Thursday 12/1. Final Projects: Administration Final Exam: Next Tuesday, 12/6 12:30, in class. Material: Everything covered from the beginning of the semester Format: Similar to mid-term; closed books Review session on Thursday HW 7:

More information

Normalized Graph cuts. by Gopalkrishna Veni School of Computing University of Utah

Normalized Graph cuts. by Gopalkrishna Veni School of Computing University of Utah Normalized Graph cuts by Gopalkrishna Veni School of Computing University of Utah Image segmentation Image segmentation is a grouping technique used for image. It is a way of dividing an image into different

More information

Big Data Analytics. Special Topics for Computer Science CSE CSE Feb 11

Big Data Analytics. Special Topics for Computer Science CSE CSE Feb 11 Big Data Analytics Special Topics for Computer Science CSE 4095-001 CSE 5095-005 Feb 11 Fei Wang Associate Professor Department of Computer Science and Engineering fei_wang@uconn.edu Clustering II Spectral

More information

CS 534: Computer Vision Segmentation and Perceptual Grouping

CS 534: Computer Vision Segmentation and Perceptual Grouping CS 534: Computer Vision Segmentation and Perceptual Grouping Ahmed Elgammal Dept of Computer Science CS 534 Segmentation - 1 Outlines Mid-level vision What is segmentation Perceptual Grouping Segmentation

More information

Mining Social Network Graphs

Mining Social Network Graphs Mining Social Network Graphs Analysis of Large Graphs: Community Detection Rafael Ferreira da Silva rafsilva@isi.edu http://rafaelsilva.com Note to other teachers and users of these slides: We would be

More information

From Pixels to Blobs

From Pixels to Blobs From Pixels to Blobs 15-463: Rendering and Image Processing Alexei Efros Today Blobs Need for blobs Extracting blobs Image Segmentation Working with binary images Mathematical Morphology Blob properties

More information

Visual Representations for Machine Learning

Visual Representations for Machine Learning Visual Representations for Machine Learning Spectral Clustering and Channel Representations Lecture 1 Spectral Clustering: introduction and confusion Michael Felsberg Klas Nordberg The Spectral Clustering

More information

Clustering appearance and shape by learning jigsaws Anitha Kannan, John Winn, Carsten Rother

Clustering appearance and shape by learning jigsaws Anitha Kannan, John Winn, Carsten Rother Clustering appearance and shape by learning jigsaws Anitha Kannan, John Winn, Carsten Rother Models for Appearance and Shape Histograms Templates discard spatial info articulation, deformation, variation

More information

6.801/866. Segmentation and Line Fitting. T. Darrell

6.801/866. Segmentation and Line Fitting. T. Darrell 6.801/866 Segmentation and Line Fitting T. Darrell Segmentation and Line Fitting Gestalt grouping Background subtraction K-Means Graph cuts Hough transform Iterative fitting (Next time: Probabilistic segmentation)

More information

Segmentation (continued)

Segmentation (continued) Segmentation (continued) Lecture 05 Computer Vision Material Citations Dr George Stockman Professor Emeritus, Michigan State University Dr Mubarak Shah Professor, University of Central Florida The Robotics

More information

Image Segmentation. Selim Aksoy. Bilkent University

Image Segmentation. Selim Aksoy. Bilkent University Image Segmentation Selim Aksoy Department of Computer Engineering Bilkent University saksoy@cs.bilkent.edu.tr Examples of grouping in vision [http://poseidon.csd.auth.gr/lab_research/latest/imgs/s peakdepvidindex_img2.jpg]

More information

Image Segmentation. Selim Aksoy. Bilkent University

Image Segmentation. Selim Aksoy. Bilkent University Image Segmentation Selim Aksoy Department of Computer Engineering Bilkent University saksoy@cs.bilkent.edu.tr Examples of grouping in vision [http://poseidon.csd.auth.gr/lab_research/latest/imgs/s peakdepvidindex_img2.jpg]

More information

Spatial-Color Pixel Classification by Spectral Clustering for Color Image Segmentation

Spatial-Color Pixel Classification by Spectral Clustering for Color Image Segmentation 2008 ICTTA Damascus (Syria), April, 2008 Spatial-Color Pixel Classification by Spectral Clustering for Color Image Segmentation Pierre-Alexandre Hébert (LASL) & L. Macaire (LAGIS) Context Summary Segmentation

More information

Color, Texture and Segmentation. CSE 455 Linda Shapiro

Color, Texture and Segmentation. CSE 455 Linda Shapiro Color, Texture and Segmentation CSE 455 Linda Shapiro Color Spaces RGB HSI/HSV CIE L*a*b YIQ and more standard for cameras hue, saturation, intensity intensity plus 2 color channels color TVs, Y is intensity

More information

Aarti Singh. Machine Learning / Slides Courtesy: Eric Xing, M. Hein & U.V. Luxburg

Aarti Singh. Machine Learning / Slides Courtesy: Eric Xing, M. Hein & U.V. Luxburg Spectral Clustering Aarti Singh Machine Learning 10-701/15-781 Apr 7, 2010 Slides Courtesy: Eric Xing, M. Hein & U.V. Luxburg 1 Data Clustering Graph Clustering Goal: Given data points X1,, Xn and similarities

More information

SGN (4 cr) Chapter 11

SGN (4 cr) Chapter 11 SGN-41006 (4 cr) Chapter 11 Clustering Jussi Tohka & Jari Niemi Department of Signal Processing Tampere University of Technology February 25, 2014 J. Tohka & J. Niemi (TUT-SGN) SGN-41006 (4 cr) Chapter

More information

CS 5614: (Big) Data Management Systems. B. Aditya Prakash Lecture #21: Graph Mining 2

CS 5614: (Big) Data Management Systems. B. Aditya Prakash Lecture #21: Graph Mining 2 CS 5614: (Big) Data Management Systems B. Aditya Prakash Lecture #21: Graph Mining 2 Networks & Communi>es We o@en think of networks being organized into modules, cluster, communi>es: VT CS 5614 2 Goal:

More information

Example 2: Straight Lines. Image Segmentation. Example 3: Lines and Circular Arcs. Example 1: Regions

Example 2: Straight Lines. Image Segmentation. Example 3: Lines and Circular Arcs. Example 1: Regions Image Segmentation Image segmentation is the operation of partitioning an image into a collection of connected sets of pixels. 1. into regions, which usually cover the image Example : Straight Lines. into

More information

Image Segmentation. Srikumar Ramalingam School of Computing University of Utah. Slides borrowed from Ross Whitaker

Image Segmentation. Srikumar Ramalingam School of Computing University of Utah. Slides borrowed from Ross Whitaker Image Segmentation Srikumar Ramalingam School of Computing University of Utah Slides borrowed from Ross Whitaker Segmentation Semantic Segmentation Indoor layout estimation What is Segmentation? Partitioning

More information

Non Overlapping Communities

Non Overlapping Communities Non Overlapping Communities Davide Mottin, Konstantina Lazaridou HassoPlattner Institute Graph Mining course Winter Semester 2016 Acknowledgements Most of this lecture is taken from: http://web.stanford.edu/class/cs224w/slides

More information

Example 1: Regions. Image Segmentation. Example 3: Lines and Circular Arcs. Example 2: Straight Lines. Region Segmentation: Segmentation Criteria

Example 1: Regions. Image Segmentation. Example 3: Lines and Circular Arcs. Example 2: Straight Lines. Region Segmentation: Segmentation Criteria Image Segmentation Image segmentation is the operation of partitioning an image into a collection of connected sets of pixels. 1. into regions, which usually cover the image Example 1: Regions. into linear

More information

A Weighted Kernel PCA Approach to Graph-Based Image Segmentation

A Weighted Kernel PCA Approach to Graph-Based Image Segmentation A Weighted Kernel PCA Approach to Graph-Based Image Segmentation Carlos Alzate Johan A. K. Suykens ESAT-SCD-SISTA Katholieke Universiteit Leuven Leuven, Belgium January 25, 2007 International Conference

More information

Lecture 11: E-M and MeanShift. CAP 5415 Fall 2007

Lecture 11: E-M and MeanShift. CAP 5415 Fall 2007 Lecture 11: E-M and MeanShift CAP 5415 Fall 2007 Review on Segmentation by Clustering Each Pixel Data Vector Example (From Comanciu and Meer) Review of k-means Let's find three clusters in this data These

More information

Machine Learning for Data Science (CS4786) Lecture 11

Machine Learning for Data Science (CS4786) Lecture 11 Machine Learning for Data Science (CS4786) Lecture 11 Spectral Clustering Course Webpage : http://www.cs.cornell.edu/courses/cs4786/2016fa/ Survey Survey Survey Competition I Out! Preliminary report of

More information

Introduction to spectral clustering

Introduction to spectral clustering Introduction to spectral clustering Denis Hamad LASL ULCO Denis.Hamad@lasl.univ-littoral.fr Philippe Biela HEI LAGIS Philippe.Biela@hei.fr Data Clustering Data clustering Data clustering is an important

More information

Segmentation and Grouping

Segmentation and Grouping Segmentation and Grouping How and what do we see? Fundamental Problems ' Focus of attention, or grouping ' What subsets of pixels do we consider as possible objects? ' All connected subsets? ' Representation

More information

Spectral Clustering X I AO ZE N G + E L HA M TA BA S SI CS E CL A S S P R ESENTATION MA RCH 1 6,

Spectral Clustering X I AO ZE N G + E L HA M TA BA S SI CS E CL A S S P R ESENTATION MA RCH 1 6, Spectral Clustering XIAO ZENG + ELHAM TABASSI CSE 902 CLASS PRESENTATION MARCH 16, 2017 1 Presentation based on 1. Von Luxburg, Ulrike. "A tutorial on spectral clustering." Statistics and computing 17.4

More information

Targil 12 : Image Segmentation. Image segmentation. Why do we need it? Image segmentation

Targil 12 : Image Segmentation. Image segmentation. Why do we need it? Image segmentation Targil : Image Segmentation Image segmentation Many slides from Steve Seitz Segment region of the image which: elongs to a single object. Looks uniform (gray levels, color ) Have the same attributes (texture

More information

Clustering. So far in the course. Clustering. Clustering. Subhransu Maji. CMPSCI 689: Machine Learning. dist(x, y) = x y 2 2

Clustering. So far in the course. Clustering. Clustering. Subhransu Maji. CMPSCI 689: Machine Learning. dist(x, y) = x y 2 2 So far in the course Clustering Subhransu Maji : Machine Learning 2 April 2015 7 April 2015 Supervised learning: learning with a teacher You had training data which was (feature, label) pairs and the goal

More information

Community Detection. Community

Community Detection. Community Community Detection Community In social sciences: Community is formed by individuals such that those within a group interact with each other more frequently than with those outside the group a.k.a. group,

More information

k-means demo Administrative Machine learning: Unsupervised learning" Assignment 5 out

k-means demo Administrative Machine learning: Unsupervised learning Assignment 5 out Machine learning: Unsupervised learning" David Kauchak cs Spring 0 adapted from: http://www.stanford.edu/class/cs76/handouts/lecture7-clustering.ppt http://www.youtube.com/watch?v=or_-y-eilqo Administrative

More information

Clustering. Subhransu Maji. CMPSCI 689: Machine Learning. 2 April April 2015

Clustering. Subhransu Maji. CMPSCI 689: Machine Learning. 2 April April 2015 Clustering Subhransu Maji CMPSCI 689: Machine Learning 2 April 2015 7 April 2015 So far in the course Supervised learning: learning with a teacher You had training data which was (feature, label) pairs

More information

CS 6140: Machine Learning Spring 2017

CS 6140: Machine Learning Spring 2017 CS 6140: Machine Learning Spring 2017 Instructor: Lu Wang College of Computer and Informa@on Science Northeastern University Webpage: www.ccs.neu.edu/home/luwang Email: luwang@ccs.neu.edu Logis@cs Grades

More information

Clustering Lecture 8. David Sontag New York University. Slides adapted from Luke Zettlemoyer, Vibhav Gogate, Carlos Guestrin, Andrew Moore, Dan Klein

Clustering Lecture 8. David Sontag New York University. Slides adapted from Luke Zettlemoyer, Vibhav Gogate, Carlos Guestrin, Andrew Moore, Dan Klein Clustering Lecture 8 David Sontag New York University Slides adapted from Luke Zettlemoyer, Vibhav Gogate, Carlos Guestrin, Andrew Moore, Dan Klein Clustering: Unsupervised learning Clustering Requires

More information

Content-based Image and Video Retrieval. Image Segmentation

Content-based Image and Video Retrieval. Image Segmentation Content-based Image and Video Retrieval Vorlesung, SS 2011 Image Segmentation 2.5.2011 / 9.5.2011 Image Segmentation One of the key problem in computer vision Identification of homogenous region in the

More information

The goals of segmentation

The goals of segmentation Image segmentation The goals of segmentation Group together similar-looking pixels for efficiency of further processing Bottom-up process Unsupervised superpixels X. Ren and J. Malik. Learning a classification

More information

Spectral Clustering. Presented by Eldad Rubinstein Based on a Tutorial by Ulrike von Luxburg TAU Big Data Processing Seminar December 14, 2014

Spectral Clustering. Presented by Eldad Rubinstein Based on a Tutorial by Ulrike von Luxburg TAU Big Data Processing Seminar December 14, 2014 Spectral Clustering Presented by Eldad Rubinstein Based on a Tutorial by Ulrike von Luxburg TAU Big Data Processing Seminar December 14, 2014 What are we going to talk about? Introduction Clustering and

More information

Segmentation Computer Vision Spring 2018, Lecture 27

Segmentation Computer Vision Spring 2018, Lecture 27 Segmentation http://www.cs.cmu.edu/~16385/ 16-385 Computer Vision Spring 218, Lecture 27 Course announcements Homework 7 is due on Sunday 6 th. - Any questions about homework 7? - How many of you have

More information

My favorite application using eigenvalues: partitioning and community detection in social networks

My favorite application using eigenvalues: partitioning and community detection in social networks My favorite application using eigenvalues: partitioning and community detection in social networks Will Hobbs February 17, 2013 Abstract Social networks are often organized into families, friendship groups,

More information

Spectral Clustering on Handwritten Digits Database

Spectral Clustering on Handwritten Digits Database October 6, 2015 Spectral Clustering on Handwritten Digits Database Danielle dmiddle1@math.umd.edu Advisor: Kasso Okoudjou kasso@umd.edu Department of Mathematics University of Maryland- College Park Advance

More information

Segmentation. Bottom Up Segmentation

Segmentation. Bottom Up Segmentation Segmentation Bottom up Segmentation Semantic Segmentation Bottom Up Segmentation 1 Segmentation as clustering Depending on what we choose as the feature space, we can group pixels in different ways. Grouping

More information

Segmentation and low-level grouping.

Segmentation and low-level grouping. Segmentation and low-level grouping. Bill Freeman, MIT 6.869 April 14, 2005 Readings: Mean shift paper and background segmentation paper. Mean shift IEEE PAMI paper by Comanici and Meer, http://www.caip.rutgers.edu/~comanici/papers/msrobustapproach.pdf

More information

CS 231A CA Session: Problem Set 4 Review. Kevin Chen May 13, 2016

CS 231A CA Session: Problem Set 4 Review. Kevin Chen May 13, 2016 CS 231A CA Session: Problem Set 4 Review Kevin Chen May 13, 2016 PS4 Outline Problem 1: Viewpoint estimation Problem 2: Segmentation Meanshift segmentation Normalized cut Problem 1: Viewpoint Estimation

More information

Image Segmentation continued Graph Based Methods. Some slides: courtesy of O. Capms, Penn State, J.Ponce and D. Fortsyth, Computer Vision Book

Image Segmentation continued Graph Based Methods. Some slides: courtesy of O. Capms, Penn State, J.Ponce and D. Fortsyth, Computer Vision Book Image Segmentation continued Graph Based Methods Some slides: courtesy of O. Capms, Penn State, J.Ponce and D. Fortsyth, Computer Vision Book Previously Binary segmentation Segmentation by thresholding

More information

CS 664 Slides #11 Image Segmentation. Prof. Dan Huttenlocher Fall 2003

CS 664 Slides #11 Image Segmentation. Prof. Dan Huttenlocher Fall 2003 CS 664 Slides #11 Image Segmentation Prof. Dan Huttenlocher Fall 2003 Image Segmentation Find regions of image that are coherent Dual of edge detection Regions vs. boundaries Related to clustering problems

More information

Normalized Cuts and Image Segmentation

Normalized Cuts and Image Segmentation Normalized Cuts and Image Segmentation Jianbo Shi and Jitendra Malik Computer Science Division University of California at Berkeley, Berkeley, CA 94720 {j shi,malik}@cs.berkeley.edu Abstract we propose

More information

Image Segmentation continued Graph Based Methods

Image Segmentation continued Graph Based Methods Image Segmentation continued Graph Based Methods Previously Images as graphs Fully-connected graph node (vertex) for every pixel link between every pair of pixels, p,q affinity weight w pq for each link

More information

STUDYING THE FEASIBILITY AND IMPORTANCE OF GRAPH-BASED IMAGE SEGMENTATION TECHNIQUES

STUDYING THE FEASIBILITY AND IMPORTANCE OF GRAPH-BASED IMAGE SEGMENTATION TECHNIQUES 25-29 JATIT. All rights reserved. STUDYING THE FEASIBILITY AND IMPORTANCE OF GRAPH-BASED IMAGE SEGMENTATION TECHNIQUES DR.S.V.KASMIR RAJA, 2 A.SHAIK ABDUL KHADIR, 3 DR.S.S.RIAZ AHAMED. Dean (Research),

More information

A Randomized Algorithm for Pairwise Clustering

A Randomized Algorithm for Pairwise Clustering A Randomized Algorithm for Pairwise Clustering Yoram Gdalyahu, Daphna Weinshall, Michael Werman Institute of Computer Science, The Hebrew University, 91904 Jerusalem, Israel {yoram,daphna,werman}@cs.huji.ac.il

More information

Heat Kernels and Diffusion Processes

Heat Kernels and Diffusion Processes Heat Kernels and Diffusion Processes Definition: University of Alicante (Spain) Matrix Computing (subject 3168 Degree in Maths) 30 hours (theory)) + 15 hours (practical assignment) Contents 1. Solving

More information

Introduction to spectral clustering

Introduction to spectral clustering Introduction to spectral clustering Vasileios Zografos zografos@isy.liu.se Klas Nordberg klas@isy.liu.se What this course is Basic introduction into the core ideas of spectral clustering Sufficient to

More information

http://www.xkcd.com/233/ Text Clustering David Kauchak cs160 Fall 2009 adapted from: http://www.stanford.edu/class/cs276/handouts/lecture17-clustering.ppt Administrative 2 nd status reports Paper review

More information

Regularized Tree Partitioning and Its Application to Unsupervised Image Segmentation

Regularized Tree Partitioning and Its Application to Unsupervised Image Segmentation FEBRUARY 2014 1 Regularized Tree Partitioning and Its Application to Unsupervised Image Segmentation Jingdong Wang, Huaizu Jiang, Yangqing Jia, Xian-Sheng Hua, Changshui Zhang, and Long Quan Abstract In

More information

A Graph Clustering Algorithm Based on Minimum and Normalized Cut

A Graph Clustering Algorithm Based on Minimum and Normalized Cut A Graph Clustering Algorithm Based on Minimum and Normalized Cut Jiabing Wang 1, Hong Peng 1, Jingsong Hu 1, and Chuangxin Yang 1, 1 School of Computer Science and Engineering, South China University of

More information

A Spectral-based Clustering Algorithm for Categorical Data Using Data Summaries (SCCADDS)

A Spectral-based Clustering Algorithm for Categorical Data Using Data Summaries (SCCADDS) A Spectral-based Clustering Algorithm for Categorical Data Using Data Summaries (SCCADDS) Eman Abdu eha90@aol.com Graduate Center The City University of New York Douglas Salane dsalane@jjay.cuny.edu Center

More information

Introduction to Machine Learning

Introduction to Machine Learning Introduction to Machine Learning Clustering Varun Chandola Computer Science & Engineering State University of New York at Buffalo Buffalo, NY, USA chandola@buffalo.edu Chandola@UB CSE 474/574 1 / 19 Outline

More information

The clustering in general is the task of grouping a set of objects in such a way that objects

The clustering in general is the task of grouping a set of objects in such a way that objects Spectral Clustering: A Graph Partitioning Point of View Yangzihao Wang Computer Science Department, University of California, Davis yzhwang@ucdavis.edu Abstract This course project provide the basic theory

More information

Data Mining. Dr. Raed Ibraheem Hamed. University of Human Development, College of Science and Technology Department of Computer Science

Data Mining. Dr. Raed Ibraheem Hamed. University of Human Development, College of Science and Technology Department of Computer Science Data Mining Dr. Raed Ibraheem Hamed University of Human Development, College of Science and Technology Department of Computer Science 06 07 Department of CS - DM - UHD Road map Cluster Analysis: Basic

More information

Spectral Graph Multisection Through Orthogonality. Huanyang Zheng and Jie Wu CIS Department, Temple University

Spectral Graph Multisection Through Orthogonality. Huanyang Zheng and Jie Wu CIS Department, Temple University Spectral Graph Multisection Through Orthogonality Huanyang Zheng and Jie Wu CIS Department, Temple University Outline Motivation Preliminary Algorithm Evaluation Future work Motivation Traditional graph

More information

Normalized Cut Approximations

Normalized Cut Approximations University of Iowa Iowa Research Online Theses and Dissertations Spring 2011 Normalized Cut Approximations William Stonewall Monroe University of Iowa Copyright 2011 William Stonewall Monroe This thesis

More information

identified and grouped together.

identified and grouped together. Segmentation ti of Images SEGMENTATION If an image has been preprocessed appropriately to remove noise and artifacts, segmentation is often the key step in interpreting the image. Image segmentation is

More information

11. Image Data Analytics. Jacobs University Visualization and Computer Graphics Lab

11. Image Data Analytics. Jacobs University Visualization and Computer Graphics Lab 11. Image Data Analytics Motivation Images (and even videos) have become a popular data format for storing information digitally. Data Analytics 377 Motivation Traditionally, scientific and medical imaging

More information

Clustering. SC4/SM4 Data Mining and Machine Learning, Hilary Term 2017 Dino Sejdinovic

Clustering. SC4/SM4 Data Mining and Machine Learning, Hilary Term 2017 Dino Sejdinovic Clustering SC4/SM4 Data Mining and Machine Learning, Hilary Term 2017 Dino Sejdinovic Clustering is one of the fundamental and ubiquitous tasks in exploratory data analysis a first intuition about the

More information

Behavioral Data Mining. Lecture 18 Clustering

Behavioral Data Mining. Lecture 18 Clustering Behavioral Data Mining Lecture 18 Clustering Outline Why? Cluster quality K-means Spectral clustering Generative Models Rationale Given a set {X i } for i = 1,,n, a clustering is a partition of the X i

More information

EE 701 ROBOT VISION. Segmentation

EE 701 ROBOT VISION. Segmentation EE 701 ROBOT VISION Regions and Image Segmentation Histogram-based Segmentation Automatic Thresholding K-means Clustering Spatial Coherence Merging and Splitting Graph Theoretic Segmentation Region Growing

More information

Normalized Cuts and Image Segmentation

Normalized Cuts and Image Segmentation University of Pennsylvania ScholarlyCommons Departmental Papers (CIS) Department of Computer & Information Science 8-1-2000 Normalized Cuts and Image Segmentation Jianbo Shi University of Pennsylvania,

More information

Graph-based Image Segmentation using K-Means Clustering and Normalised Cuts

Graph-based Image Segmentation using K-Means Clustering and Normalised Cuts 0 Fourth International Conference on Computational Intelligence, Communication Systems and Networks Graph-based Image Segmentation using K-Means Clustering and Normalised Cuts Mei Yeen Choong, Wei Leong

More information

Convolutional Neural Networks on Graphs with Fast Localized Spectral Filtering

Convolutional Neural Networks on Graphs with Fast Localized Spectral Filtering Convolutional Neural Networks on Graphs with Fast Localized Spectral Filtering May 12 2017 2 Content 1. Introduction 2. Proposed Technique 2.1 Learning Fast Localized Spectral Filters 2.2 Graph Coarsening

More information

CSE 473/573 Computer Vision and Image Processing (CVIP) Ifeoma Nwogu. Lectures 21 & 22 Segmentation and clustering

CSE 473/573 Computer Vision and Image Processing (CVIP) Ifeoma Nwogu. Lectures 21 & 22 Segmentation and clustering CSE 473/573 Computer Vision and Image Processing (CVIP) Ifeoma Nwogu Lectures 21 & 22 Segmentation and clustering 1 Schedule Last class We started on segmentation Today Segmentation continued Readings

More information

NOVEL GRAPH BASED METHOD FOR IMAGE SEGMENTATION

NOVEL GRAPH BASED METHOD FOR IMAGE SEGMENTATION NOVEL GRAPH BASED METHOD FOR IMAGE SEGMENTATION 1 Dr. S. V.KASMIR RAJA, 2 A. SHAIK ABDUL KHADIR, 3 Dr. S. S. RIAZ AHAMED 1 Dean (Research), SRM University, Chennai, TamilNadu, India 2 Lecturer (SG), Dept

More information

Normalized Cuts and Image Segmentation. Jianbo Shi and Jitendra Malik. University of California at Berkeley, Berkeley, CA 94720

Normalized Cuts and Image Segmentation. Jianbo Shi and Jitendra Malik. University of California at Berkeley, Berkeley, CA 94720 Proc. of the IEEE Conf. on Comp. Vision and Pattern Recognition, San Juan, Puerto Rico, June 1997 Normalized Cuts and Image Segmentation Jianbo Shi and Jitendra alik Computer Science Division University

More information

Normalized Cuts Clustering with Prior Knowledge and a Pre-clustering Stage

Normalized Cuts Clustering with Prior Knowledge and a Pre-clustering Stage Normalized Cuts Clustering with Prior Knowledge and a Pre-clustering Stage D. Peluffo-Ordoñez 1, A. E. Castro-Ospina 1, D. Chavez-Chamorro 1, C. D. Acosta-Medina 1, and G. Castellanos-Dominguez 1 1- Signal

More information

B553 Lecture 12: Global Optimization

B553 Lecture 12: Global Optimization B553 Lecture 12: Global Optimization Kris Hauser February 20, 2012 Most of the techniques we have examined in prior lectures only deal with local optimization, so that we can only guarantee convergence

More information

CSCI-B609: A Theorist s Toolkit, Fall 2016 Sept. 6, Firstly let s consider a real world problem: community detection.

CSCI-B609: A Theorist s Toolkit, Fall 2016 Sept. 6, Firstly let s consider a real world problem: community detection. CSCI-B609: A Theorist s Toolkit, Fall 016 Sept. 6, 016 Lecture 03: The Sparsest Cut Problem and Cheeger s Inequality Lecturer: Yuan Zhou Scribe: Xuan Dong We will continue studying the spectral graph theory

More information

Object Classification Problem

Object Classification Problem HIERARCHICAL OBJECT CATEGORIZATION" Gregory Griffin and Pietro Perona. Learning and Using Taxonomies For Fast Visual Categorization. CVPR 2008 Marcin Marszalek and Cordelia Schmid. Constructing Category

More information

Math 778S Spectral Graph Theory Handout #2: Basic graph theory

Math 778S Spectral Graph Theory Handout #2: Basic graph theory Math 778S Spectral Graph Theory Handout #: Basic graph theory Graph theory was founded by the great Swiss mathematician Leonhard Euler (1707-178) after he solved the Königsberg Bridge problem: Is it possible

More information

Lecture 11: Classification

Lecture 11: Classification Lecture 11: Classification 1 2009-04-28 Patrik Malm Centre for Image Analysis Swedish University of Agricultural Sciences Uppsala University 2 Reading instructions Chapters for this lecture 12.1 12.2 in

More information

Spectral Segmentation with Multiscale Graph Decomposition

Spectral Segmentation with Multiscale Graph Decomposition Spectral Segmentation with Multiscale Graph Decomposition Timothée Cour 1 Florence Bénézit 2 Jianbo Shi 3 1,3 Computer and Information Science 2 Applied Mathematics Department University of Pennsylvania

More information

TELCOM2125: Network Science and Analysis

TELCOM2125: Network Science and Analysis School of Information Sciences University of Pittsburgh TELCOM2125: Network Science and Analysis Konstantinos Pelechrinis Spring 2015 2 Part 4: Dividing Networks into Clusters The problem l Graph partitioning

More information

Extracting Communities from Networks

Extracting Communities from Networks Extracting Communities from Networks Ji Zhu Department of Statistics, University of Michigan Joint work with Yunpeng Zhao and Elizaveta Levina Outline Review of community detection Community extraction

More information

Social Data Management Communities

Social Data Management Communities Social Data Management Communities Antoine Amarilli 1, Silviu Maniu 2 January 9th, 2018 1 Télécom ParisTech 2 Université Paris-Sud 1/20 Table of contents Communities in Graphs 2/20 Graph Communities Communities

More information

Image Segmentation With Maximum Cuts

Image Segmentation With Maximum Cuts Image Segmentation With Maximum Cuts Slav Petrov University of California at Berkeley slav@petrovi.de Spring 2005 Abstract This paper presents an alternative approach to the image segmentation problem.

More information

Finding and Visualizing Graph Clusters Using PageRank Optimization. Fan Chung and Alexander Tsiatas, UCSD WAW 2010

Finding and Visualizing Graph Clusters Using PageRank Optimization. Fan Chung and Alexander Tsiatas, UCSD WAW 2010 Finding and Visualizing Graph Clusters Using PageRank Optimization Fan Chung and Alexander Tsiatas, UCSD WAW 2010 What is graph clustering? The division of a graph into several partitions. Clusters should

More information

Hierarchical Multi level Approach to graph clustering

Hierarchical Multi level Approach to graph clustering Hierarchical Multi level Approach to graph clustering by: Neda Shahidi neda@cs.utexas.edu Cesar mantilla, cesar.mantilla@mail.utexas.edu Advisor: Dr. Inderjit Dhillon Introduction Data sets can be presented

More information

Improving Image Segmentation Quality Via Graph Theory

Improving Image Segmentation Quality Via Graph Theory International Symposium on Computers & Informatics (ISCI 05) Improving Image Segmentation Quality Via Graph Theory Xiangxiang Li, Songhao Zhu School of Automatic, Nanjing University of Post and Telecommunications,

More information

Evaluating Segmentation

Evaluating Segmentation Evaluating Segmentation David Martin dmartin@cs.bc.edu Computer Science Department Boston College CVPR 2004 Graph-Based Image Segmentation Tutorial 1 How do you know when a segmentation algorithm is good?

More information

How and what do we see? Segmentation and Grouping. Fundamental Problems. Polyhedral objects. Reducing the combinatorics of pose estimation

How and what do we see? Segmentation and Grouping. Fundamental Problems. Polyhedral objects. Reducing the combinatorics of pose estimation Segmentation and Grouping Fundamental Problems ' Focus of attention, or grouping ' What subsets of piels do we consider as possible objects? ' All connected subsets? ' Representation ' How do we model

More information

CSE 258 Lecture 6. Web Mining and Recommender Systems. Community Detection

CSE 258 Lecture 6. Web Mining and Recommender Systems. Community Detection CSE 258 Lecture 6 Web Mining and Recommender Systems Community Detection Dimensionality reduction Goal: take high-dimensional data, and describe it compactly using a small number of dimensions Assumption:

More information

Integer and Combinatorial Optimization: Clustering Problems

Integer and Combinatorial Optimization: Clustering Problems Integer and Combinatorial Optimization: Clustering Problems John E. Mitchell Department of Mathematical Sciences RPI, Troy, NY 12180 USA February 2019 Mitchell Clustering Problems 1 / 14 Clustering Clustering

More information

3D-NCuts: Adapting Normalized Cuts to 3D Triangulated Surface Segmentation

3D-NCuts: Adapting Normalized Cuts to 3D Triangulated Surface Segmentation 3D-NCuts: Adapting Normalized Cuts to 3D Triangulated Surface Segmentation Zahra Toony 1, Denis Laurendeau 1, Philippe Giguère 2 and Christian Gagné 1 1 Computer Vision and System Laboratory, Department

More information

Lecture 7: Segmentation. Thursday, Sept 20

Lecture 7: Segmentation. Thursday, Sept 20 Lecture 7: Segmentation Thursday, Sept 20 Outline Why segmentation? Gestalt properties, fun illusions and/or revealing examples Clustering Hierarchical K-means Mean Shift Graph-theoretic Normalized cuts

More information

CS290H Graph Laplacians and Spectra. Final Project Report. Categorization of biomedical articles with spectral clustering. By Arvind C.

CS290H Graph Laplacians and Spectra. Final Project Report. Categorization of biomedical articles with spectral clustering. By Arvind C. CS290H Graph Laplacians and Spectra Final Project Report Categorization of biomedical articles with spectral clustering By Arvind C. Rajasekaran Abstract Clustering is the process of grouping together

More information

CSE 158 Lecture 6. Web Mining and Recommender Systems. Community Detection

CSE 158 Lecture 6. Web Mining and Recommender Systems. Community Detection CSE 158 Lecture 6 Web Mining and Recommender Systems Community Detection Dimensionality reduction Goal: take high-dimensional data, and describe it compactly using a small number of dimensions Assumption:

More information

Outline of this Talk

Outline of this Talk Outline of this Talk Data Association associate common detections across frames matching up who is who Two frames: linear assignment problem Generalize to three or more frames increasing solution quality

More information

Hierarchical Clustering

Hierarchical Clustering What is clustering Partitioning of a data set into subsets. A cluster is a group of relatively homogeneous cases or observations Hierarchical Clustering Mikhail Dozmorov Fall 2016 2/61 What is clustering

More information

Joint Shape Segmentation

Joint Shape Segmentation Joint Shape Segmentation Motivations Structural similarity of segmentations Extraneous geometric clues Single shape segmentation [Chen et al. 09] Joint shape segmentation [Huang et al. 11] Motivations

More information

Scalable Clustering of Signed Networks Using Balance Normalized Cut

Scalable Clustering of Signed Networks Using Balance Normalized Cut Scalable Clustering of Signed Networks Using Balance Normalized Cut Kai-Yang Chiang,, Inderjit S. Dhillon The 21st ACM International Conference on Information and Knowledge Management (CIKM 2012) Oct.

More information

Graph Based Image Segmentation

Graph Based Image Segmentation AUTOMATYKA 2011 Tom 15 Zeszyt 3 Anna Fabijañska* Graph Based Image Segmentation 1. Introduction Image segmentation is one of the fundamental problems in machine vision. In general it aims at extracting

More information

Multiscale Analysis of Dynamic Graphs

Multiscale Analysis of Dynamic Graphs Multiscale Analysis of Dynamic Graphs Mauro Maggioni Department of Mathematics and Computer Science Duke University ICIAM, Vancouver - 7/22/2011 Joint work: J. Lee (Duke, Stanford) Partial support: DARPA,

More information