Received Jan 5, 2014 Revised Feb 8, 2014 Accepted Feb 17, 2014 Median filter is a non-linear filter used in image processing for impulse noise removal. It finds its typical application in the situations where edges are to be preserved for higher level operations like segmentation, object recognition etc. This paper presents an accurate and efficient noise detection and filtering algorithm for i...

Earlier research has shown that the problem of optimal weighted median filtering with structural constraints can be formulated as a nonconvex nonlinear programming problem in general. However, its high computational complexity and poor performance due to its nonconvex nature prohibit it from practical applications. In this paper, we shall show that the design problem can be formulated as a conv...

Within the last two decades a small group of researchers has built a useful, nontrivial theory of nonlinear signal processing around the median-related filters known as rank-order filters, order-statistic filters, weighted median filters, and stack filters. This required significant effort to overcome the bias, both in education and research, toward linear theory, which has been dominant since ...

This paper presents a new method for filtering the impulse noise in images. This is a two-stage approach in which an impulse is first detected by thresholding the energy of the prediction error in a block-based twodimensional linear prediction of the image intensity. The median filter is subsequently applied to the pixels detected to be corrupted by the impulse noise. Simulation results show th...

Vector (multichannel) signal processing has arisen in the last decades as a major area of interest. The classical single-channel (scalar valued) processing techniques cannot deal with the interchannel dependencies, yielding to the development of new methods. This paper investigates two approaches to the median filtering of vector valued signals: filtering based on the reduced ordering in the sp...

The impact of noise on image will degrade its feature. Suppression or removal of noise in 2D images would be very worth in medical image processing, satellite image processing and various other domains. Switching median filters outperform standard median filters in the removal of impulse noise due to their capability of filtering candidate noisy pixels and leaving other pixels intact. The BDND ...

Image denoising by block matching and threedimensionaltransform filtering (BM3D) is a two steps state-ofthe-art algorithm that uses the redundancy of similar blocks innoisy image for removing noise. Similar blocks which can havesome overlap are found by a block matching method and groupedto make 3-D blocks for 3-D transform filtering. In this paper wepropose a new block grouping algorithm in th...

This paper presents a review on digital image filtering techniques. The main emphasis is on median filtering and its extended versions like hybrid median filtering, relaxed median filtering etc. It is found that still median filtering demands some sort of enhancements as it is best for salt and pepper noise only. By conducting a survey suitable gaps are found in existing literature. In the end ...

The scalar median filter (SMF) is often used to reduce noise in scalar geophysical data. We present an extension of the SMF to a vector median filter (VMF) for suppressing noise contained in geophysical data represented by multidimensional, multicomponent vector fields. Although the SMF can be applied to each component of a vector field individually, the VMF is applied to all components simulta...