Digital Image Processing NET 404) ) Introduction and Overview Chapter 1 2012 Teacher: Remah W. AlKhatib

Contents lecture will cover: What is a digital image? What is digital image processing? History of digital image processing State of the art examples of digital image processing Key stages or components in digital image processing

What is an image? Image A 2D function f (x, y) that can be observed by human visual system x and y are spatial (Plane) coordinates Amplitude of f at a point is intensity or gray level of image at that point

What is an image? Thebitmap representation Also called “raster or pixel maps” representation An image is broken up into a grid

What is a Digital Image? A digital image is a representation of a two dimensional image as a finite set of digital values, called picture elements or pixels

What is a Digital Image? (cont…) Pixel values typically represent gray levels, colors, heights, opacities etc Digitization implies that a digital image is an approximation of a real scene

What is a Digital Image? (cont…) Common image formats include: 1sample per point (B&W or Grayscale) 3 samples per point (Red, Green, and Blue) 4 samples per point (Red, Green, Blue, and “Alpha”, a.k.a. Opacity) For most of this course we will focus on grey-scale images

Digital Image Color images have 3 values per pixel; monochrome images have1 value per pixel.

What is Digital Image Processing? Refers to processing digital images by means of operations on digital computer. Digital image processing focuses on two major tasks: Improvement of pictorial information for human interpretation Processing of image data for storage, transmission and representation for autonomous machine perception

Several fields deal with images Computer Graphics The creation of images. Image Processing and Image Analysis Mainly concerned with interpreting a given image The enhancement or other manipulation of the image The result of which is usually another images. Image Understanding (Computer Vision) The analysis of image content.

Image processing Disciplines

A Historical Overview of DIP Newspaper industry used Bartlane cable picture transmission system to send pictures by submarine cable between London and New York in 1920s

Early Improvement The number of distinct gray levels coded by Bartlane system was improved from 5 to 15 by the end of 1920s

The Born of Digital Computers The images in previous slides are digital; but they are NOT considered as the results of DIP What do we mean by Digital Image Processing Processing digital images by a digital computer

The Boom of Digital Images in the Last 20 Years Acquisition Digital cameras, scanners MRI and Ultrasound imaging Infrared and microwave imaging Transmission Internet, wireless communication Display Printers, LCD monitor, digital TV

Soar Into Outer Space

A Physical Perspective of Image Acquisition Extend the capabilities of human vision systems From visible spectrum to non-visible electromagnetic power spectrum From close-distance sensing to remote sensing

Visible (I): Photography

Visible (II): Motion Pictures

Visible (III): Law Enhancement and Biometrics

Visible (IV): Light Microscopy

Visible (V): Remote Sensing

Beyond Visible (I): Thermal Images

Beyond Visible (II): Radar Images

Beyond Visible (III): MRI and Astronomy

Beyond Visible (IV): Medical Diagnostics