An Introduction to Pattern Recognition (Part One)

Download Report

Transcript An Introduction to Pattern Recognition (Part One)

Pattern Recognition

Ku-Yaw Chang

[email protected]

Assistant Professor, Department of Computer Science and Information Engineering Da-Yeh University

Outline

Introduction Features and Classes Supervised v.s. Unsupervised Statistical v.s. Structural (Syntactic) Statistical Decision Theory 2004/03/01 Pattern Recognition 2

Introduction

Pattern Recognition (PR)  Automatic detection or classification of objects or events  Given a collection of objects belonging to a predefined set of classes and a set of measurements on these objects, identify the class of membership of each of these objects by a suitable analysis of the measurements.

2004/03/01 Pattern Recognition 3

Introduction

Applications of PR  Medicine  Weather forecasting  Automated industrial inspection  Geology   Agriculture … 2004/03/01 Pattern Recognition 4

Introduction

A little girl three years of age is sitting on her mother’s lap; they are reading a picture book together.

“What is that?” asks the little girl, pointing to the big letter “O” with which the page starts, as is so often found in children’s picture books.

“That is an ‘O’.” 2004/03/01 Pattern Recognition 5

Introduction

They turn the page.

“O,” says the little girl, pointing to the sun in a picture.

“No, that is the sun.” And from that moment on the little girl knows and distinguishes “O”s and suns.

2004/03/01 Pattern Recognition 6

Introduction

Discussion How does the little girl do that?

2004/03/01 Pattern Recognition 7

Features and Classes

Features  Measurements or properties used to classify the objects Classes  Types or categories into which the objects are classified 2004/03/01 Pattern Recognition 8

Features and Classes

Features  Perimeter the length of a region’s boundary  Compactness (perimeter) 2 /area Classes  Circle : 12.56 (4 Pi)  Square : 16 2004/03/01 Pattern Recognition 9

Features and Classes

Discussion Give examples in our daily life?

 Features  Classes 2004/03/01 Pattern Recognition 10

Features and Classes

Discussion Challenges to finding and defining  Features  Classes 2004/03/01 Pattern Recognition 11