image_processing and application

7/31/2019 Image_Processing and Application

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NICE TO MEET YOU


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Dr. D.S. Guru

Department of Studies in Computer Science,

University of Mysore,

Mysore, INDIA


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About my place : Mysore

A city of palaces, gardens, shady avenues and sacred temples.

A historical place.

Retains some of the charm of the old world with its many institutionsthat propagate Carnatic Classical music and dance.

It is called a beautiful and cultured daughter city of mother India.

Palace

St. Philominas Church Holy Temples


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Brindavan Garden National Park

Falls Mysore Zoo Bird Sanctuary


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MANASAGANGOTHRI CAMPUS

University of Mysore


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IMAGE PROCESSING


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Image?

x

y

f(x,y)

O


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PROCESSING:

Analysis + Understanding

IMAGE:

A two dimensional light intensity function

Analog Image : f(xR, y R) vR = i(x,y) * r(x,y)

SamplingQuantization

Digital Image : f(xZ, yZ) vZ


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Image Acquisition Process


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Two Dimensional Representation of an Image

Memory Requirement?


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Image

An image is non-textual informationthat can be displayed and printed.

Images can be from real world orvirtual

Described as spatial arrays of values

The smallest addressable imageelement is called PIXEL (pictureelement). The array is called a bitmap


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Why Image Processing?

To improve the visual quality of an image for human

interpretation

To analyze the contents of the image for autonomousmachine perception

Image Enhancement


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Low Contrast Image

Its Histogram

High Contrast Image

Stretched Histogram

Image Enhancement


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Low quality imagesImages after processing


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Equalization


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Star treck team


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Enhanced to acolor image

Encrypted Image Decrypted Image

Water

markingapplication

Autonomous Machine Perception


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Region to be inspected

(Picture of a tunnel)

A Robot

Identified Defective RegionClose lookup

Autonomous Machine Perception

Automation of Tile inspection


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In a continuous productionprocess, all dried roof tilesare automatically inspectedfor cracks, deformations,dimensional correctness, andcolor.

The inspection speed isabout 40 tiles per minute.Defective tiles are eliminatedfrom the production processbefore further refinementtakes place.

Courtesy: Thuringian research program "Image Processing, PatternRecognition and Engineering Vision Systems" (Germany)

Automation of Tile inspection

Quality Assurance

M di l Di i


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Medical Diagnosis

X-ray Image Binary Image Noise eliminated

Skeletonization Angle Measurement


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Oblitered Image

Deciphered Image

Forensic

Application

Thresholdingoperation

Enhanced Image

Median Filtering

N b l t id tifi ti


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The vehicle approached the secured area, and starts the cycle

by stepping over a magnetic loop detector (which is the mostpopular vehicle sensor). The loop detector senses the car and

its presence is signaled to the LPR unit.

Number plate identification


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The LPR unit activates the illumination (invisible Infra-

red in most cases) and takes pictures of the front or rear

plates from the LPR camera (shown at the left side of

the gate). The images of the vehicle include the plateand the pixel information is read by the LPR unit's

image processing hardware (the frame grabber).


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The LPR unit analyzes the image with different image

processing software algorithms, enhances the image, detects

the plate position, extracts the plate string, and identifies the

fonts using special artificial intelligence methods (such asNeural Networks)


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The LPR unit checks if the vehicle appears on a predefined

list of authorized cars, and if found - it signals to open the

gate by activating its relay. The unit can also switch on a

green "go-ahead" light or red "stop" light. The unit can alsodisplay a Welcome! message with personalized data.


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The authorized vehicle enters into the secured

area. After passing the gate its detector closes the

gate. Now the system waits for the next vehicle to

approach the secured area


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A Number Plate Recognition

system


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The plate number is used to produce a violation

fine on speed or red-light systems The manualprocess of preparing a violation fine is replaced by

an automated process which reduces the time. The

fines can be viewed and paid on-line.


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Image segmentation

Cheque validation


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Stages in processing

Image acquisition

Preprocessing

Segmentation

Representationand

Description

Recognition and

Interpretation

A

An application

S

Solution

Knowledge Base


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Image Formats

Image capturing formats: the format in which imageis created

Image storage format: the format in which imagesare stored (often transmitted)

In bit maps, the values are binary numbers

In color images, the values correspond to RGB components

While storing images, additional information may be storedalong with pixels, like width, height, author, etc.


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RIFF:Resource Interchange File Format

GIF:Graphics Interchange Format TIFF:Tagged Image File Format

JPEG:Joint Photographic Experts Group

PostScript:

PBM:Portable BitMap

BMP:Bitamp

Image Formats


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TIFFFormat

TIFF was developed by Aldus and Microsoft.

TIFF uses 4-byte integer file offsets to store image

data, with the consequence that a TIFF file cannothave more than 4 Gigabytes of raster data.

Strengths: TIFF is primarily designed for rasterdata interchange. It's main strengths are a highlyflexible and platform-independent format which issupported by numerous image processingapplications.


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BMP Format

Windows bitmap files are stored in a device-independentbitmap (DIB) format that allows Windows to display thebitmap on any type of display device.

The default filename extension of a Windows DIB fileis .BMP.

Bitmap-File Structures: Each bitmap file contains abitmap-file header, a bitmap-information header, a color

table, and an array of bytes that defines the bitmap bits.

The bitmap-file header contains information about thetype, size, and layout of a device-independent bitmap file.The header is defined as a BITMAPFILEHEADERstructure.


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Standard Color spaces:

Grayscale

Pseudo color (any size) RGB

CMYK


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The RGB Color Model

The Primary colors:

R (red) G (green) B (blue)

0 --- off lowest intensity

1 --- on highest intensity

A linear combination of all three colors with differentintensity levels

G


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(0,1,1)cyan

(0,1,0)green

(1,1,1)white

(1,1,0)

yellow

(1,0,1)magenta

(0,0,1)blue

(0,0,0)black

gray axis

B

R(1,0,0)red


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CMYK Color Model

Short for Cyan-Magenta-Yellow-Black.

A color model in which all colors aredescribed as a mixture of these four Processcolors.

CMYK is the standard color model used inoffset printing for full-color documents

Because such printing uses inks of these fourbasic colors, it is often called four-colorprinting.


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Pixels Relationships

Neighbors of pixel pi

1. Four Neighbors : N4(pi) = {(x, y-1), (x+1, y), (x, y+1), (x-1, y)}

2.Diagonal Neighbors : ND(p

i) = {(x+1, y-1), (x+1, y+1), (x-1, y+1),

(x-1, y-1)}

3.Eight Neighbors : N8(pi) = N4(pi) ND(pi)

x-1, y-1 x, y-1 x+1, y-1

x-1, y pi (x, y) x+1, y

x-1, y+1 x, y+1 x+1, y+1

Pixel Connectivity


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Pixel Connectivity

4-Connectivity : Pixels p and q are four connected if

1. p and q bear values in V 2. p N4(q)

D-Connectivity : Pixels p and q are diagonally connected if

1. p and q bear values in V 2. p ND(q)

8-Connectivity : Pixels p and q are eight connected if

1. p and q bear values in V 2. p N8(q)


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m-connectivity: Pixels p and q are mixed connected if

1. p and q bear values in V

2. p N4(q) or p ND(q) and N4(p) N4(q) =

0 1 1

0 1 0

0 0 1

0 1 1

0 1 0

0 0 1

0 1 1

0 1 0

0 0 1

Labeling of Connected Components


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E E C F F F F F

G G G G G G

G G G

G G

G G

R A

B B B B B

C D D D D B

C C D D D B

E E C C F F J F

E E E C F F J F

E E H I I I J J

G = Region 1;A = Region 2R = B = Region 3;C = Region 4;D=F=Region 5;E= Region 6;J= Region 7;

H=Region 8;I= Region 9;

III

III

IV V

VI

VIII IX

VII

III

III

IV

V

VII

VI

4-Connected Component 8-Connected Component

G = Region 1;A = Region 2R = B = C= H= Region 3;D=F=Region 4;E= Region 5;J= Region 6;

I= Region 7;

4-connected

8-connected


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In Summary

Introduction

Major Goals

Applications

Stages


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EDUCATION

Enhancing ones quality through

Dedication,Understanding and

Commitment with an

Aspiration to become a member of a team

Involved in

Offline / Online development of

Nation

-D.S. Guru

No(w)

Questions!?


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T H A N K Y O U


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Dr. D.S.G


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Review Questions1. What is an image? How do you convert an analog image into a digital

image?

2. Explain the process of image acquisition.

3. How does computer represent a digital image?

4. What is the smallest addressable element of an image?

5. What are the objectives of image processing?

6. Mention at least four applications of image processing.

7. Write the different stages in image processing.

8. What is the role of knowledge base in image processing?

9. What are different image formats available?

10.Explain RGB color space.

11.Discuss on the importance of pixel connectivity.

12.Solve the problems of chapter 2.


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Review Assignments

1. Write a program to read and display an imagecreated in MS Paint software (BMP format).

2. Reduce the size of an image by the factor 2X2 bymerging four neighboring pixels and see the effect.

3. Write a program to read images in different formats.

4. Write program to label the connected componentsusing 4, 8 and m connectivity.

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