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    Iterative histogram matching algorithm for chromosome image enhancement based on statistical moments

    , Article Proceedings - International Symposium on Biomedical Imaging ; 2012 , Pages 214-217 ; 19457928 (ISSN) ; 9781457718588 (ISBN) Ehsani, S. P ; Mousavi, H. S ; Khalaj, B. H ; Sharif University of Technology
    IEEE  2012
    Abstract
    Vivid banding pattern of the chromosome image is a crucial part for diagnosis in karyotype medical test. Furthermore, thriving computer aided segmentation and classification depend on the initial image quality. In this paper, we propose an adaptive and iterative histogram matching algorithm for chromosome contrast enhancement especially in banding patterns which is one of the most important information laid in chromosome image. Objective histogram, with which the initial image needs to be matched, is created based on processes on the initial image histogram. Calculation of statistical moments of image histogram and determination of parameters in each step of iteration based on these moments... 

    Evaluation of Effective Factors on The Mammographic Images Utilizing Monte Carlo Simulation

    , M.Sc. Thesis Sharif University of Technology Khodajou Chokami, Hamid Reza (Author) ; Sohrabpour, Mostafa (Supervisor)
    Abstract
    The Scattered radiation is the principal factor affecting the quality of the digital and screen-film mammography images. The contrast improvement factor and bucky factor which are also referred to as the benefit and risk of the anti-scattered grid cannot be properly assessed without a detailed knowledge of the scattered radiation. In this work the scatter to primary ratio has been calculated and an anti-scatter grid has been designed based on the reduction of the scattered radiation to reduce the patient dose to a minimum level and to improve the image quality simultaneously.The MCNPX 2.6.0 Monte Carlo code has been used to improve the geometry of the anti-scatter grid to both reduce the... 

    Chromosome image contrast enhancement using adaptive, iterative histogram matching

    , Article 2011 7th Iranian Conference on Machine Vision and Image Processing, MVIP 2011 - Proceedings, 16 November 2011 through 17 November 2011 ; 2011 ; 9781457715358 (ISBN) Ehsani, S. P ; Mousavi, H. S ; Khalaj, B. H ; Sharif University of Technology
    2011
    Abstract
    Vivid banding patterns in medical images of chromosomes are a vital feature for karyotyping and chromosome classification. The chromosome image quality may be degraded by many phenomenon such as staining, sample defectness and imaging conditions. Thus, an image enhancement processing algorithm is needed before classification of chromosomes. In this paper, we propose an adaptive and iterative histogram matching (AIHM) algorithm for chromosome contrast enhancement especially in banding patterns. The reference histogram, with which the initial image needs to be matched, is created based on some processes on the initial image histogram. Usage of raw information in the histogram of initial image... 

    Design of linear anti-scatter grid geometry with optimum performance for screen-film and digital mammography systems

    , Article Physics in Medicine and Biology ; Volume 60, Issue 15 , July , 2015 , Pages 5753-5765 ; 00319155 (ISSN) Khodajou Chokami, H ; Sohrabpour, M ; Sharif University of Technology
    Institute of Physics Publishing  2015
    Abstract
    A detailed 3D Monte Carlo simulation of the grid geometrical parameters in screen-film mammography (SFM) and digital mammography (DM) systems has been performed. A combination of IEC 60627:2013 international standard conditions and other more clinically relevant parameters were used for this simulation. Accuracy of our results has been benchmarked with previously published data and good agreement has been obtained. Calculations in a wide range of linear anti-scatter grid geometries have been carried out. The evaluated parameters for the SFM system were the Bucky factor (BF) and contrast improvement factor (CIF) and for the DM system it was signal differenceto- noise ratio improvement factor...