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Colour Image Segmentation Using Perceptual Colour Difference Saliency Algorithm

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Colour Image Segmentation Using Perceptual Colour Difference Saliency Algorithm COLOUR IMAGE SEGMENTATION USING PERCEPTUAL COLOUR DIFFERENCE SALIENCY ALGORITHM By TAIWO, TUNMIKE BUKOLA (21557473) Submitted in fulfilment of the requirements of the MASTERS DEGREE IN INFORMATION AND COMMUNICATION TECHNNOLOGY in the DEPARTMENT OF INFORMATION TECHNOLOGY in the FACULTY OF ACCOUNTING AND INFORMATICS at DURBAN UNIVERSITY OF TECHNOLOGY July 2017 DECLARATION I, Taiwo, Tunmike Bukola hereby declares that this dissertation is my own work and has not been previously submitted in any form to any other university or institution of higher learning by other persons or myself. I further declare that all the sources of information used in this dissertation have been acknowledged. _________________________ ____________________ Taiwo, Tunmike Bukola Date Approved for final submission Supervisor: _______________________ ______________________ Professor O. O. Olugbara Date PhD (Computer Science) Co-Supervisor: __________________ ______________________ Dr. Delene Heukelman Date DTech (Information Technology) ii DEDICATION This dissertation is dedicated to my family for their support, encouragement and motivation throughout the period of this study. iii ACKNOWLEDGEMENTS First and foremost, my profound appreciation goes to the Almighty Jehovah, the giver of life and wisdom, for His limitless love, inspiration and strength throughout the period of this study. I return to Him all the glory, honour and adoration. I am particularly grateful to my supervisor, Prof. Oludayo Olugbara. A humble genius in image processing research field, his mentorship on both professional and personal levels was tremendous. Since the beginning of this study, he has always been there not only as my supervisor, but a father and guardian. I wouldn’t be writing this today if I had a different supervisor. I really appreciate all the valuable time he spent in helping me with programming and new concepts with reference to my research work. I was fortunate to work with such a kind and encouraging professor over the years. I would also like to sincerely thank my co-supervisor, Dr. Delene Heukelman for her constructive and thoughtful suggestions. Your advice and direction was invaluable and you always made time to read through my work. I would also like to express my gratitude to Mrs. O. S. Olugbara for the role she played throughout the journey. I would like to thank all friends in and out of the ICT and Society Research group, who made any sort of support and motivation into this dissertation. The support from Postgraduate Research and Support, Durban University of Technology in offering me scholarship to pursue this degree is gratefully acknowledged. Last, but definitely not the least, I wish to express my deepest gratitude, love and affection to my family. They deserve a special mention for their love, support, prayers, encouragement, motivation and dedication to make this degree a success. I appreciate you all. iv TABLE OF CONTENTS DECLARATION .................................................................................................................................... ii DEDICATION ....................................................................................................................................... iii ACKNOWLEDGEMENTS ................................................................................................................... iv TABLE OF CONTENTS ........................................................................................................................ v LIST OF FIGURES ............................................................................................................................. viii LIST OF TABLES .................................................................................................................................. x Abstract .................................................................................................................................................. xi CHAPTER ONE ..................................................................................................................................... 1 INTRODUCTION .................................................................................................................................. 1 1.1 Research problem statement ............................................................................................................. 4 1.2 Research question ............................................................................................................................. 4 1.3 Research Aim and Objectives ........................................................................................................... 5 1.4 Research Methodology ..................................................................................................................... 5 1.5 Research Contributions ..................................................................................................................... 6 1.6 Dissertation Synopsis ........................................................................................................................ 7 Chapter TWO .......................................................................................................................................... 8 LITERATURE REVIEW ....................................................................................................................... 8 2.1 Image Segmentation .......................................................................................................................... 8 2.1.1 Region based Image Segmentation Methods ................................................................................. 9 2.1.3 Pixel based Image Segmentation methods ................................................................................... 10 2.2 Histogram thresholding algorithms ................................................................................................. 11 2.2.1 Otsu thresholding algorithm......................................................................................................... 13 2.2.2 Multilevel Thresholding algorithms ............................................................................................. 13 2.2.3 Nature Inspired Optimization Algorithms ................................................................................... 16 2.3 Cluster Analysis .............................................................................................................................. 18 2.3.1 K-means clustering algorithm ...................................................................................................... 20 2.3.2 Fuzzy C-means Algorithm ........................................................................................................... 22 2.4 Improvements of clustering algorithms .......................................................................................... 23 2.4.1 Improved Variants of K-means algorithm ................................................................................... 24 2.4.2 Improved Variants of the Fuzzy C-means Algorithm .................................................................. 28 2.5 Colour Image Segmentation Methods ............................................................................................. 34 2.5.2 Colour Based Saliency Segmentation Methods ........................................................................... 35 2.5.3 Image Segmentation Based on Different Colour Models ............................................................ 42 v 2.6 Image Segmentation Performance Evaluation ................................................................................ 49 2.6 1 Benchmark Data sets .................................................................................................................... 49 2.6.2 Image segmentation Evaluation Methods .................................................................................... 50 2.7 Chapter summary ............................................................................................................................ 53 CHAPTER THREE .............................................................................................................................. 54 METHODOLOGY OF THE STUDY .................................................................................................. 54 3.1 Image Datasets Acquisition ............................................................................................................ 54 3.1.2 ISBI 2016 Challenge Dataset ....................................................................................................... 55 3.1.3 Pedro Hispano Hospital Dataset .................................................................................................. 57 3.1.4 Microsoft Research Asia Dataset ................................................................................................. 59 3.1.5 Extended Complex Scene Saliency Dataset ................................................................................. 60 3.2.1 Colour Image Transformation ...................................................................................................... 61 3.2.2 Luminance Image enhancement ................................................................................................... 63 3.2.3 Salient Pixel Computation ........................................................................................................... 64 3.2.4 Image Artefact filtering ...............................................................................................................
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