Resolution Enhancement of CT Images Using Multiple Low Resolution Sub-pixel Shifted Images

8/16/2019 Resolution Enhancement of CT Images Using Multiple Low Resolution Sub-pixel Shifted Images

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Resolution Enhancement ofCT Images Using MultipleLow Resolution Sub-pixel

Shifted Images

Pesented b!Mohammad "iful #a$ue

%epatment of EEE&angladesh Uni'esit! of Engineeing

and Technolog!


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Intoduction

Radiation dose

Computational time

mputed tomogaph! (CT) is a medical imagingdalit! to obtain the intenal coss-sectional image

uman bod! using x-a! po*ection data+

wo ma*o concens of CT imaging ae


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Challenges to o'ecome

• Reducing the adiation dose inceasesthe image noise

• Reducing the computational timelowes the image esolution


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Computed Tomogaph! ,'e'iew

&loc. diagam of steps in'ol'ed inCT imaging

/-a!souce

%etecto

SignalPocessin

g

Reconstuction %ispla!


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Liteatue Re'iew

• Thee ae two main appoaches of CTimage econstuction,

(i) 0ilteed bac.-po*ection (0&P)

techni$ue (ii) Iteati'e econstuction (IR)techni$ue such as S"RT+

• 0&P techni$ue is computationall!e1cient but e$uies moe adiationdose as compae to IR+

•

IR techni$ue e$uies lass adiation


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Poposed Method , &asicConcept

Sub-pixel ShiftedImages• Two images of the

same scene shiftedb! a faction aesub-pixel shiftedimages+

• Contains newinfomation aboutthe same scene+


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Reconstuction of Sub-pixel ShiftedImage


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#R image Reconstuction

&! cubic intepolation2we poduce an #Rimage fom each of•

the LR images+

• The images ae then aligned accodingl! andthe 3nal #R image is fomed as a weightedcombination of all the intepolated images


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Simulation Result , PhantomImage

S"RT (PS4R 5 66+78 d&) PRPSE% (PS4R 5 66+9: d&)

4ISE-0REE C4%ITI4


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S"RT (PS4R 5 67+;6 d&)

PRPSE% (PS4R 5 6:+8< d&)

S4R 5 69 d&


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S"RT (PS4R 5:9+;< d&)

PRPSE% (PS4R 5 67+=8 d&)

S4R 5 66 d&


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Simulation Result , ChestImage

S"RT (PS4R 5 :>+88 d&) PRPSE% (PS4R 5 68+;6 d&)

4ISE-0REE C4%ITI4


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Conclusion

• The poposed method can poducebette image $ualit! as compaed to

con'entional techni$ue withoutinceasing the adiation dose

• Since we econstuct image fom low

esolution images2 the o'ealleconstuction time is less than thatof con'entional techni$ue foidentical image si?e+


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Than. @ou

Documents

Resolution Enhancement of CT Images Using Multiple Low Resolution Sub-pixel Shifted Images