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Vol: 52(66) No: 3 / September 2007 Noise Removal from Images Using Some Rank Order Filters Cezar Popescu Department of Automation and Applied Informatics, “Politehnica” University of Timisoara, Faculty of Automation and Computers, Bd. V. Parvan 2, Timisoara, Romania, phone: 40 256 403246, e-mail: cezar.popescu@aut.upt.ro Keywords: image enhancement, image reconstruction, random noise, median filter, percentile filter Abstract The papers deals with some rank order filters used for noise removal from gray level images. A linear uniform filter is used as a reference to evaluate the performance of nonlinear filters. The particular case of the median filter is implemented, together with the generalized case of the percentile filter. Some improvements and tunings are added by introducing thresholds as a condition in the filters. Different noises are applied to images in the experiments. Finally, a complete image reconstruction from salt and pepper noise corruption is presented. References [1]Barner, Kenneth E., Sarhan, Ahmad M., Hardie, Russel C., “Partition Based Weighted Sum Filters for Image Restoration”, IEEE Transactions on Image Processing, Vol. 8. No. 5, May 1999. [2]Chan, Tony F., Osher, Stanley, Shen, Jianhong, “The Digital TV Filter and Nonlinear Denoising”, IEEE Transactions on Image Processing, Vol. 10. No. 2, February 2001. [3]Eng, How-Lung, Ma, Kai-Kuang, “Noise Adaptive Soft-Switching Median Filter”. IEEE Transactions on Image Processing, Vol. 10. No. 2, February 2001. [4]Gonzales, R.C., Woods, R.E., “Digital Image Processing”, Prentice Hall, New Jersey, 2002. [5]Jahne, Berndt, “Digital Image Processing”, Springer Verlag, Berlin, 2002. [6]Lin, Jean-Hsang, Ansari, Nirwan, Li, Jinhui, “Nonlinear Filtering by Threshold Decomposition”, IEEE Transactions on Image Processing, Vol. 8. No. 7, July 1999. |