Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Digital Image Processing and Edge Detection
Seda Albayrak
Computer Science Department of Istanbul Bilgi Univercity

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

1

Introduction

2

Examples of fields that use Digital Image Processing

3

Visibility: Depends on human perception

4

Fundamental Definitions

5

Analysis of edge detection algorithms

6

Questions

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Do you think that is all?

Figure: Visible Light

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

More than your eyes can see

Figure: Electromagnetic Spectrum
Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Gamma-Ray Imaging

Figure: The gamma-ray moon

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

X-Ray Imaging

Figure: X-ray photo of a one year old girl

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Ultraviolet Imaging

Figure: Ultaviolet and visible light of galaxies

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Imaging in infrared bands

Figure: TV’s remote and temperature control

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Imaging in microwave band

Figure: Plate reading
Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Are you fallible about what you see?

Figure: Examples of some well-known optical illusions and
simultaneous contrast

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

What do you see in this picture?

What is digital image?
What is pixel?
What is intensity level?
What is edge detection?
What is edge detection used for?

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Digital convolution

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Taking first derivative of a greylevel image

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Roberts, Prewitt and Sobel edge detectors

Figure: Masks of first order edge detection algorithms
Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Laplacian of a Gaussian edge detection algorithm

What about noise?

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

What is the difference?

Which one is best?
Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

An example of a simple way

Seda Albayrak

Digital Image Processing and Edge Detection
Outline
Introduction
Examples of fields that use Digital Image Processing
Visibility: Depends on human perception
Fundamental Definitions
Analysis of edge detection algorithms
Questions

Any Questions?

Wake up! Any questions?

Seda Albayrak

Digital Image Processing and Edge Detection

Digital Image Processing and Edge Detection

  • 1.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Digital Image Processing and Edge Detection Seda Albayrak Computer Science Department of Istanbul Bilgi Univercity Seda Albayrak Digital Image Processing and Edge Detection
  • 2.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions 1 Introduction 2 Examples of fields that use Digital Image Processing 3 Visibility: Depends on human perception 4 Fundamental Definitions 5 Analysis of edge detection algorithms 6 Questions Seda Albayrak Digital Image Processing and Edge Detection
  • 3.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Do you think that is all? Figure: Visible Light Seda Albayrak Digital Image Processing and Edge Detection
  • 4.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions More than your eyes can see Figure: Electromagnetic Spectrum Seda Albayrak Digital Image Processing and Edge Detection
  • 5.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Gamma-Ray Imaging Figure: The gamma-ray moon Seda Albayrak Digital Image Processing and Edge Detection
  • 6.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions X-Ray Imaging Figure: X-ray photo of a one year old girl Seda Albayrak Digital Image Processing and Edge Detection
  • 7.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Ultraviolet Imaging Figure: Ultaviolet and visible light of galaxies Seda Albayrak Digital Image Processing and Edge Detection
  • 8.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Imaging in infrared bands Figure: TV’s remote and temperature control Seda Albayrak Digital Image Processing and Edge Detection
  • 9.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Imaging in microwave band Figure: Plate reading Seda Albayrak Digital Image Processing and Edge Detection
  • 10.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Are you fallible about what you see? Figure: Examples of some well-known optical illusions and simultaneous contrast Seda Albayrak Digital Image Processing and Edge Detection
  • 11.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions What do you see in this picture? What is digital image? What is pixel? What is intensity level? What is edge detection? What is edge detection used for? Seda Albayrak Digital Image Processing and Edge Detection
  • 12.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Digital convolution Seda Albayrak Digital Image Processing and Edge Detection
  • 13.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Taking first derivative of a greylevel image Seda Albayrak Digital Image Processing and Edge Detection
  • 14.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Roberts, Prewitt and Sobel edge detectors Figure: Masks of first order edge detection algorithms Seda Albayrak Digital Image Processing and Edge Detection
  • 15.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Laplacian of a Gaussian edge detection algorithm What about noise? Seda Albayrak Digital Image Processing and Edge Detection
  • 16.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions What is the difference? Which one is best? Seda Albayrak Digital Image Processing and Edge Detection
  • 17.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions An example of a simple way Seda Albayrak Digital Image Processing and Edge Detection
  • 18.
    Outline Introduction Examples of fieldsthat use Digital Image Processing Visibility: Depends on human perception Fundamental Definitions Analysis of edge detection algorithms Questions Any Questions? Wake up! Any questions? Seda Albayrak Digital Image Processing and Edge Detection