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                            All Graduate Theses and Dissertations                                                                                                           Graduate Studies 
                            5-2009 
                            A Computational A Computational GeometrGeometry Appry Approach toach to Digital Image o Digital Image ContContour our 
                            ExtrExtraction action 
                            Pedro J. Tejada 
                            Utah State University 
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                            Tejada, Pedro J., "A Computational Geometry Approach to Digital Image Contour Extraction" (2009). All 
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                     ACOMPUTATIONALGEOMETRYAPPROACHTO
                       DIGITAL IMAGE CONTOUR EXTRACTION
                                    by
                                Pedro J. Tejada
                          Athesis submitted in partial fulfillment
                            of the requirements for the degree
                                     of
                              MASTEROFSCIENCE
                                     in
                                Computer Science
             Approved:
             Dr. Minghui Jiang        Dr. Xiaojun Qi
             Major Professor          Committee Member
             Dr. Nicholas Flann       Dr. Byron R. Burnham
             Committee Member         Dean of Graduate Studies
                             UTAHSTATEUNIVERSITY
                                  Logan, Utah
                                    2009
                                                                                                      ii
                                                        c
                                            Copyright   
 Pedro J. Tejada 2009
                                                     All Rights Reserved
                                                  iii
                            Abstract
                      AComputational Geometry Approach to
                       Digital Image Contour Extraction
                              by
                       Pedro J. Tejada, Master of Science
                         Utah State University, 2009
           Major Professor: Dr. Minghui Jiang
           Department: Computer Science
             Wepresentamethodforextracting contours fromdigital images, usingtechniques from
           computational geometry. Our approach is different from traditional pixel-based methods
           in image processing. Instead of working directly with pixels, we extract a set of oriented
           feature points from the input digital images, then apply classical geometric techniques, such
           as clustering, linking, and simplification, to find contours among these points. Experiments
           on synthetic and natural images show that our method can effectively extract contours,
           even from images with considerable noise; moreover, the extracted contours have a very
           compact representation.
                                             (176 pages)