image enhancement final - copy

7/30/2019 Image Enhancement Final - Copy

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PresentedBy:

DIGITALIMAGEENHANCEMENT

AMAAN SYED

A leading area in the field of

computer graphics and image

processing

SYNOPSISPRESENTAIONON


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TOPICS TO DISCUSS

TITLEOFDISSERTATION

WHATISDIGITALIMAGEPROCESSING

WHYDIGITALIMAGEPROCESSINGINNECESSARY

APPLICATIONAREA

STEPSINIMAGEPROCESSING

DISSERTATIONCATEGORY

IMAGEENHANCEMENT

HARDWAREANDSOFTWAREREQUIREMENT

FUTURESCOPEANDENHANCEMENT


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T

I

T

L

E


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StudyandAnalysisofdigitalImageEnhancementTechnique


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Onepictureisworthmorethantenthousandwords.

Anonymous

Interestindigitalimageprocessingmethodsstemsfrom

twoprincipalapplicationareas:

improvement of pictorial information for humaninterpretation

processingofimagedataforstorage,transmissionand

representationforautonomousmachineperception.


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DIGITALIMAGEPROCESSING


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Animagemaybedefinedasatwo-dimensionalfunction,f(x,y).wherexandyareknownasspatial coordinatesandfunctionf

foraparticularpair(x,y)iscalledtheintensityorgraylevelof

theimageatthatpoint.

These elements are calledpicture elements, image elements,

pels,andpixels.Pixelisthetermusedmostwidelytodenotethe

elementsofadigitalimage.

Adigitalimageiscomposedofafinitenumberofelements,each

ofwhichhasaparticularlocation andvalue.

Location=(x,y)

Value=f(x,y)


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Digital image processing refers to the processing of

digital images by means of a digital computer by applying somefunctiontochangethevalue(f(x,y))ofthepixeltoobtainadifferent

functionvalue

f(x+1,y-1)

f(x+1,y)

f(x+1,y+1)

f(x-1,y--1)

f(x-1,y)

f(x-1,y+1)

f(x,y-1)

f(x,y)

f(x,y+1)


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Whenrepresentedasdiscreteform/numbers,brightnesscanbe

added,subtracted,multiplied,divided,andi.e.theimagecanbe

manipulated which was not possible if the image was

representedasaphotograph.

Lowcontrast Mediumcontrast Highcontrast


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WHYDIGITALIMAGEPROCESSING


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Wehumansarelimitedtothevisualbandoftheelectromagnetic

(EM)spectrum.

Machines imaging is needed that cover almost the entire EM

spectrum, ranging from gamma to radio waves. They can

operate on images generated by sources that humans are not

accustomed to associating with images. These include

ultrasound, electron microscopy, and computer-generated

images.


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Iftheimagesareleftdistorted,itwouldrenderanydataextraction

fromthedistortedimage.

Machinegeneratedimagingmaynotalwaysbeofgoodquality

orwemaybeinterestedonlyinsomeoftheregionoftheimage

orsomedistortionmayoccur.


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APPLICATION

AREAS


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X-RayImaging

pollutionpatterns

aerialtrafficcontrolaerialphotography

Detectionofminerals

Detectionoflandusage

healthofindigenousplants

MEDICALDIAGNOSIS

computerizedaxialtomography(CAT)

Gamma-RayImaging

Computervision

Angiography

Opticalsorting

SPACEPROGRAM

FeaturedetectionMicroscopeimageprocessing

Biologydeforestation

Remotesensing

Machinevision

Explorationgeophysics

Automobileindustry


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STEPSIN

IMAGEPROCESSING


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The aim of image enhancement is to improve the

interpretability or perception of information

inimagesforhumanviewers,ortoprovide`better'inputfor

otherautomatedimageprocessingtechniques.

Imageenhancementtechniquescanbedividedinto:

Spatialdomainmethods,whichoperatedirectlyonpixels

frequencydomainmethods,whichoperateontheFourier

transformofanimage.


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ImageisNOTPerfectSometimes


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Greyscalemanipulation

ThesimplestformofoperationiswhentheoperatorTactsonly

ona1x1pixelneighborhoodintheinputimage,thatis TF(x,y)

depends on the value of F only at (x, y). This is a grey scale

transformationormappingalsoknownaspointtopointoperation

In this case any pixel with a grey level below the chosenthreshold in the input image gets mapped to 0 in the output

imageandOtherpixelsaremappedto255.


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Supposeanimageispredominantlydark.Thenitshistogramwouldbe

skewedtowardsthelowerendofthegreyscaleandalltheimagedetail

iscompressedintothedarkendofthehistogram.

0 50 100 150 200

HistogramEqualization

Histogram of an image represents the relative frequency of

occurrenceofvariousgraylevelsintheimage

3000

2500

2000

1500

1000

500

0


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Histograminformationrevealsthatimageisunder-exposed

0 50 100 150 200 250

4

3.5

3

2.5

2

1.5

1

0.5

0

x 10

4


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0 50 100 150 200 250

7000

6000

5000

4000

3000

2000

1000

0

Over-exposedimage


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Application(I):DigitalPhotography

Application(II):IrisRecognition


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LOWPASSFILTERSHIGHPASSFILTER

MEANFILTER

MEDIANFILTER

MIDFILTER

MAXIMUMFILTER

MINIMUMFILTERALPHATRIMMEDMEANFILTER

ALPHACOMPLEMENTARYTRIMMEDMEAN

FILTER

RANGEFILTER

GEOMETRICMEANFILTERHARMONICMEAN FILTER

POWERMEANFILTER


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There is a broad area of dissertation as provided by theesteemed university. This topic Digital Image

Enhancement focusesondifferenttechniquesthatareused

forimageprocessing/imageenhancement.

The word digital is emphasizes the processing of digital

imagebyusingdigitalcomputers.Digitalimagescomposed

of finite no. of elements and the processing/enhancement

functionisappliedontheseelementsonly.

Thisprojectcomesunderthecategoryof

DigitalImageProcessingand

Computergraphics

This gives a detailed studyand analysis of different image

enhancementtechniques.

DISSERTATIONCATEGORY


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HARDWAREREQUIREMENT:-

IntelPentium IVProcessororaboveRAMsize512MBminimum.

HardDisk40GBminimum.

HARDWAREANDSOFTWARE

REQUIREMENT

TECHNOLOGIESUSED:-

CPROGRAMMINGLANGUAGE

VISUALC++6.0IDE

Windows98/NT/2000/XP/Windows7


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FURTHERENHANCEMENT

Thisprojectgivesdetailedanalysisoftheimageproperties andimageenhancementtechniques.Asimageprocessing isavastareaandnewtechnologiesaregraduallyevolving daybyday.

Thereforethefuturescopeisverybrightforthistopic.Thiscanbe

associatedwithdifferentotherareassuchas.

Pattern

recognition

Machine

learning

Virtual

security

Robotics

e.t.c

FUTURESCOPEAND


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Thankyou

image enhancement final - copy

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