1
Chapter-1
Introduction
1) Define Image, Digital Image, Digital Image Processing, Pixel
2) Write down the Application areas of Digital Image Processing.
3) Discuse the Fundamental Steps in Digital Image Processing.
4) Name the components of an Image Processing system and describe them in short.
Introduction
Ques:
Define Image, Digital Image, Digital Image Processing, Pixel.
Image:
Any two-dimensional function, f(x, y) that bears information considered as an image.
Wher x and y are spatial (plane) coordinates.
Digital Image:
When x, y and the amplitude values of f are all finite discrete quantities, then it is called
Digital Image.
Digital Image Processing
To process digital images by means of a digital computer is referred to as Digital Image
Processing.
Display
Imaging Sampling Digital Digital On-line
&
system Quantization Storage Computer Buffer
Record
Object Observe Digitize Store Process Refresh/
store Output
Fig. A typical Digital Image Processing Sequence
Pixel:
A digital image is composed of a finite number of elements, each of which has a particular
location and value. These elements are referred to as picture elements, image elements, pels
and pixels.
Origin
0 1 N-1
y
0
1
One pixel
M-1
x
2
Ques:
Write down the Application areas of Digital Image Processing.
Application areas of Digital Image Processing
i) Gammaa Ray Imaging
ii) X-ray Imaging
iii) Imaging in the Ultraviolet Band
iv) Imaging in the visible and Infrared Bands
v) Imaging in the Microwave Band
vi) Imaging in the Radio Band
Ques:
Discuss the Fundamental steps in Digital Image Processing.
Fundamental steps in Digital Image Processing
Output of these processes generally are image attributes
Output of the processes generally are images
Fig: Fundamental steps in Digital Image Processing.
Wavelets and
Color image multiresolution Morphological
All the methodologies
processing that can be applied to
processing images for
Compression different purpose and possibly
processing
with different objectives are as follows-
Image acquisitionImage
restoration Segmentation
Gave some hints regarding the origin of digital images.
Involves preprocessing, such as scaling.
Image Representation
Image Enhancement
Enhancement Knowledge base & description
Bring out detail that i obscured, or simply to highlight certain features of interest in an
image. Image Object
Problem Enhancement recognition
domain
3
Represent the image information clearly.
Subjective.
e.g., Fourier Transform.
Image Restoration
Deals with improving the appearance of an image.
Objective.
Color Image Processing
An area that has been gaining in importance because of the significant increase in the use
of digital images over the Internet.
Simplifies object identification and extraction from a scene.
Wavelets
Foundation for representing images in various degrees of resolution.
Compression
Reducing the storage required to save an image, or the bandwidth required to transmit it.
Morphological Processing
Extracting image components that are useful in the representation and description of
shape.
Segmentation
Partition an image into its constituent parts or objects.
Representation & Description
Always follow the output of a segmentation stage, which usually is raw pixel data,
constituting either the boundary of a region or all the points in the region itself.
Description (or feature selection), deals with extracting attributes that result in some
quantitative information of interest for differentiating one class of objects from another.
Recognition
Assigns a label to an object lased on its descriptors.
There is an interaction between these processing modules and the knowledge base.
Knowledge about a problem domain is coded into an image processing system in the form of
a knowledge database.
Ques:
Name the components of an Image Processing System and describe them in short.
Components of an Image Processing System
The basic components comprising a typical general-purpose system used for digital image
processing is shown in the figure-
4
Network
Image displays Mass storage
Computer
Specialized Image
Hardcopy image Processing
processing Software
hardware
Image Sensors
Problem
Domain
Fig: Components of a general-purpose image processing system
