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Suryanarayana, S.
- Estimation and Removal of Gaussian Noise in Digital Images
Authors
1 Dept of ECE, ACE Engg.College, Hyderabad, A.P, IN
2 Hyderabad Central University, Hyderabad, A.P, IN
3 R&D, JNTU, Hyderabad, A.P, IN
4 Dept of ECE, GNITS, Hyderabad, A.P, IN
Source
International Journal of Electronics and Communication Engineering, Vol 5, No 1 (2012), Pagination: 23-33Abstract
In this paper a novel algorithm for Gaussian noise estimation and removal is proposed by using 3x3 sub windows in which the test pixel appears. The standard deviation(STD) for all sub-windows are used to define reference STD(σref)and minimum(σmin) and maximum (σmax) standard deviations. The average STD (σavg) is then calculated as the average of those STDs of all sub-windows whose STD falls with in the range of [σmin, σmax]. This σavg is used for detecting and removing additive Gaussian noise. The performance is compared with that of the standard mean filter. The proposed scheme is outperforming than the standard mean filter.Keywords
Additive Gaussian Noise, Standard Deviation, Sub-windows
References
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- RWA in the Presence of Wavelength Conversion in WDM Networks
Authors
1 CVR College of Engineering affiliated to JNTU, Hyderabad, IN
2 Mallareddy Institute of Tech & Science, Secunderabad, affiliated to JNTU, Hyderabad, IN
3 JNTU College of Engg, Karimnagar, affiliated to JNTU, Hyderabad, IN
Source
Networking and Communication Engineering, Vol 2, No 3 (2010), Pagination: 71-75Abstract
Blocking probability has been one of the key performance indexes in the design of wavelength-routed all-optical WDM networks. Existing research has demonstrated that an effective Routing and Wavelength Assignment (RWA) algorithm and wavelength conversion are two primary vehicles for improving the blocking performance.. The Weighted least-congestion routing and first-fit wavelength assignment (WLCR-FF) algorithm considers both the current traffic load and the route lengths jointly. In this paper, Numerical study was conducted over ring and mesh-torus and NSFNET topology. A comparison was made between WLCR-FF and a wide variety of existing routing algorithms like static routing, fixed-alternate routing and least-loaded routing. The results conclusively demonstrate that the WLCR-FF algorithm can achieve much better blocking performance in the presence of sparse or/and full wavelength conversion.