Inlämning av Examensarbete / Submission of Thesis

Ahmed Shah Mehadi MEE09:40 , pp. 89. TEK/avd. för signalbehandling, 2009.

The work

Författare / Author: Ahmed Shah Mehadi
adshahmehadi@gmail.com
Titel / Title: Implementing Efficient iterative 3D Deconvolution for Microscopy
Översatt titel / Translated title: Implementering av effektiv iterativ 3D-avfaltning för mikroskopi
Abstrakt Abstract:

Both Gauss-Seidel Iterative 3D deconvolution and Richardson-Lucy like algorithms are used due to their stability and high quality results in high noise microscopic medical image processing. An approach to determine the difference between these two algorithms is presented in this paper. It is shown that the convergence rate and the quality of these two algorithms are influenced by the size of the point spread function (PSF). Larger PSF sizes causes faster convergence but this effect falls off for larger sizes . It is furthermore shown that the relaxation factor and the number of iterations are influencing the convergence rate of the two algorithms. It has been found that increasing relaxation factor and number of iterations improve convergence and can reduce the error of the deblurred image. It also found that overrelaxation converges faster than underrelaxation for small number of iterations. However, it can be achieved smaller final error with under-relaxation. The choice of underrelaxation factor and overrelaxation factor value are highly problem specific and different from one type of images. In addition, when it comes to 3D iterative deconvolution, the influence of boundary conditions for these two algorithms is discussed. Implementation aspects are discussed and it is concluded that cache memory is vital for achieving a fast implementation of iterative 3D deconvolution. A mix of the two algorithms have been developed and compared with the previously mentioned Gauss-Seidel and the Richardson-Lucy-like algorithms. The experiments indicate that, if the value of the relaxation parameter is optimized, then the Richardson-Lucy-like algorithm has the best performance for 3D iterative deconvolution.

Populärvetenskaplig beskrivning / Popular science summary: Upplösningen på bilder tagna med mikroskop är idag begränsad av diffraktion. För att komma runt detta förbättras bilden digitalt utifrån en matematisk modell av den fysiska processen. Den här avhandlingen jämför två algoritmer för att lösa ekvationerna: Richardson-Lucy och Gauss-Seidel. Vidare studeras effekten av parametrar såsom utbredningen av ljusspridfunktionen och regularisering av ekvationslösaren.
Ämnesord / Subject: Signalbehandling - Signal Processing
Telekommunikation - Telecommunications
Mathematics\General
Nyckelord / Keywords: Iterative 3D deconvolution, Convergence rate, Boundary conditions, Point Spread function, Relaxation factor

Publication info

Dokument id / Document id:
Program:/ Programme Magisterprogram i Elektroteknik / Master of Science in Electrical Engineering
Registreringsdatum / Date of registration: 06/23/2009
Uppsatstyp / Type of thesis: Magisterarbete/Master's Thesis (60 credits)

Context

Handledare / Supervisor: Johan Henriksson
johan.henriksson@ki.se
Examinator / Examiner: Benny Sällberg
Organisation / Organisation: Blekinge Institute of Technology
Institution / School: TEK/avd. för signalbehandling
S-372 25 Ronneby
+46 455 38 50 00
I samarbete med / In co-operation with: Karolinska Institute
Anmärkningar / Comments:

Mobile: (0046)762778136

Files & Access

Bifogad uppsats fil(er) / Files attached: masters_thesis_mee09_40.pdf (2505 kB, öppnas i nytt fönster)