Image analysis using wavelets part.1

IMAGE IMAGE ANALYSIS USING ANALYSIS USING

WAVELETSWAVELETS

PARTPART--1 : Fundamentals of Image 1 : Fundamentals of Image ProcessingProcessing

PARTPART--2 2 : Wavelets: Wavelets

Presentation on……..Presentation on……..

PARTPART--2 2 : Wavelets: Wavelets

By

Prof.B.B.S.KUMARProf.B.B.S.KUMARResearch Scholar, Assistant Professor,Research Scholar, Assistant Professor,

RajarajeswariRajarajeswari College of Engineering,College of Engineering,

Bangalore, IndiaBangalore, India

1FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

PARTPART--1 1 : Fundamentals of Image : Fundamentals of Image

ProcessingProcessingProcessingProcessing

FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India2

PRESENTATION OUTLINEPRESENTATION OUTLINE

•• What is Image?What is Image?

•• What What is Digital Image Processing?is Digital Image Processing?

•• Sampling and ReconstructionSampling and Reconstruction

•• Color Image ProcessingColor Image Processing

•• The Origins of Digital Image ProcessingThe Origins of Digital Image Processing

•• Fundamental Steps in Digital Image Fundamental Steps in Digital Image

ProcessingProcessing

•• Components of an Image Processing SystemComponents of an Image Processing System

3FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

One picture is worth more than ten thousand words

4FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

5FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

WHAT IS IMAGEWHAT IS IMAGE??

• Image is physical quantity

• Converted into electrical signal by transducers

• Consist of an Data and mathematical function

and represented in 1-D signal

• Using 1-D signal processing is called signal • Using 1-D signal processing is called signal

processing

6FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

What is Digital Image Processing?What is Digital Image Processing?

• Electrical Signal is Sampled, Quantized and Encoded –

DSP

• Image Signal is Sampled, Quantized and Encoded – DIP

Digital Image Processing

• f(x,y): A 2-dimensional function, where x and y are

spatial(plane) coordinates, and the amplitude of f at any

pair of coordinates (x,y) is called the intensity or gray

level of the image at that point called a digital image.

7FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

• x size: 512, y size : 512, gray levels: 256

Gray scale image : 262KB, Color image : 786KB

• Digital image: x, y, and the amplitude values of f are

all finite, discrete quantities

• Image Mathematical representation in Matrix form m

x n, m as rows and n as columns x n, m as rows and n as columns

• Digital image is composed of a finite number of

elements, these elements are called picture elements,

image elements, pels and pixels

• A pixel is a sample of a continuous function8

FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Image Formats

• TIFF -Tagged Image File Format (.tiff., tif)

• JPEG -Joint Photographic Experts Group

(.jpg., jpeg)

• GIF -Graphics Interchange Format (.gif)

• BMP -Windows Bitmap (.bmp)• BMP -Windows Bitmap (.bmp)

• PNG -Portable Network Graphics (.png)

• XWD -X Window Dump (.xwd)

9FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Properties of Images

• Spatial resolution

Width pixels/width cm and height pixels/ height cm

• Intensity resolution

Intensity bits/intensity range (per channel)Intensity bits/intensity range (per channel)

• Number of channels

RGB is 3 channels, grayscale is one channel

10FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Electromagnetic Spectrum

11FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Image Errors• Spatial Aliasing

Not enough spatial resolution

• Intensity Quantization

Not enough intensity resolution

Two Issues• Sampling and Reconstruction• Sampling and Reconstruction

Creating and displaying images while reducing spatial aliasing

errors

• Halftoning Techniques

Dealing with intensity quantization

12FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Aliasing• Artifacts caused by too low sampling frequency

(undersampling) or improper reconstruction

• Undersampling rate determined by Nyquist limit (Shannon’s sampling theorem)

Aliasing in computer graphicsIn graphics, two major typesIn graphics, two major types

• Spatial aliasing

Problems in individual images

• Temporal aliasing

Problems in image sequences (motion)

13FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

SAMPLING AND RECONSTRUCTIONSAMPLING AND RECONSTRUCTION

14FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Color Image ProcessingColor Image Processing

Color Image Processing divided into two major

areas:

– Full color(Sensor, color TV camera and color scanner)

– Pseudocolor(color to particular monochrome intensity

or range of intensities)or range of intensities)

Quality of a chromatic light source:

– Radiance(energy(Watts) flows from the light source),

– Luminance(measure of energy(lumens) source)

– Brightness(impossible to measure)

15FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

• Human eye absorption

– Primary colors-Red, Green and Blue(RGB)

– Wavelength:R-700nm, G-346.1nm, B-435.8nm

• Primary colors can be produce the secondary colors of light

– Magenta(R+B), Cyan(G+B) and Yellow(R+G)

Contd……

– Magenta(R+B), Cyan(G+B) and Yellow(R+G)

• Digital technologies

– CRT(Cathode Ray Tube),

– LCD(Liquid Crystal Displays) ,

– TFTs(Thin Film transistors)

– Plasma Devices

16FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Color Models(color space or color system)Color Models(color space or color system)

– RGB(Red, Green and Blue)

– CMY(Cyan, Magenta and Yellow)

– CMYK(Cyan, Magenta, Yellow and Black)

– HIS(Hue, Saturation and Intensity)

– Red, Green and Blue- each 8-bit image– Red, Green and Blue- each 8-bit image

– RGB color pixel-24 bits

– The total number of colors in a 24-RGB image is (28)3=16,777,216

– 24-bit RGB image are limited to 256 colors

– 216 common colors are used.

– 40 colors unknown.17

FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

The Origins of Digital Image The Origins of Digital Image

ProcessingProcessing

• One of the first applications of digital images

was in the newspaper industry, when pictures

were first sent by submarine cable between

London and New York.London and New York.

18FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Better

Quality

19FDP Lecture-1, Dept. of ECE, RRCE,

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1515--Tone Tone

EquipmentEquipment

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From computers, meaningful image processing From computers, meaningful image processing

tasks appearedtasks appeared

21FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Electromagnetic Energy Spectrum

22FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Gamma-

Ray

Imaging

23FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

X-ray

Imaging

24FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Imaging in Imaging in

the

Ultraviolet

Band

25FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Imaging Imaging

in the

Visible

and

Infrared

Bands

26FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Remote sensing

27FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

28FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Weather Weather Observation, visible and infraredbands

29FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Infrared Infrared

Imaging

30FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

31FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Automated

Visual

Inspection

32FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

33FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Imaging in Imaging in

the

Microwave

Band

34FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Imaging

in the

Radio

Band

MRI

35FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

36FDP Lecture-1, Dept. of ECE, RRCE,

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SoundSound

Examples in which Other Imaging Modalities Are Used

SoundSound

37FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

UltrasoundUltrasound

38FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Electron

MicroscopeMicroscope

39FDP Lecture-1, Dept. of ECE, RRCE,

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Images Images

generated generated generated generated

by by

computerscomputers

40FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

41FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Fundamental Steps in Digital Image Fundamental Steps in Digital Image

ProcessingProcessing

42FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

Computerized Processes– Low level Processes

– Mid Level Processes

– Higher level Processes

• Low Level Processes– Image preprocessing-reduce noise, contrast enhancement and image

sharpening- inputs and outputs are images

• Mid Level Processes• Mid Level Processes– Segmentation(partitioning an image into regions or objects)

– Inputs are images

– Outputs are attritubes extracted from those images(edges, contours, and the identity of individual objects)

• Higher level Processes– Making sense of recognozied objects with human vision– Human vision perception is very important

43FDP Lecture-1, Dept. of ECE, RRCE,

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Components of an Image Processing

System

44FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India

To be continued…………Next

PARTPART--2:Wavelets2:Wavelets

45FDP Lecture-1, Dept. of ECE, RRCE,

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THANK YOU!THANK YOU!

46FDP Lecture-1, Dept. of ECE, RRCE,

Bangalore, India