Impulse noise

About: Impulse noise is a research topic. Over the lifetime, 4816 publications have been published within this topic receiving 63970 citations.

The augmented lagrange multipliers method for matrix completion from corrupted samplings with application to mixed Gaussian-impulse noise removal.

Abstract: This paper studies the problem of the restoration of images corrupted by mixed Gaussian-impulse noise. In recent years, low-rank matrix reconstruction has become a research hotspot in many scientific and engineering domains such as machine learning, image processing, computer vision and bioinformatics, which mainly involves the problem of matrix completion and robust principal component analysis, namely recovering a low-rank matrix from an incomplete but accurate sampling subset of its entries and from an observed data matrix with an unknown fraction of its entries being arbitrarily corrupted, respectively. Inspired by these ideas, we consider the problem of recovering a low-rank matrix from an incomplete sampling subset of its entries with an unknown fraction of the samplings contaminated by arbitrary errors, which is defined as the problem of matrix completion from corrupted samplings and modeled as a convex optimization problem that minimizes a combination of the nuclear norm and the l(1)-norm in this paper. Meanwhile, we put forward a novel and effective algorithm called augmented Lagrange multipliers to exactly solve the problem. For mixed Gaussian-impulse noise removal, we regard it as the problem of matrix completion from corrupted samplings, and restore the noisy image following an impulse-detecting procedure. Compared with some existing methods for mixed noise removal, the recovery quality performance of our method is dominant if images possess low-rank features such as geometrically regular textures and similar structured contents; especially when the density of impulse noise is relatively high and the variance of Gaussian noise is small, our method can outperform the traditional methods significantly not only in the simultaneous removal of Gaussian noise and impulse noise, and the restoration ability for a low-rank image matrix, but also in the preservation of textures and details in the image.

Method and apparatus for reducing the effects of impulse noise in Loran-C receivers

Abstract: The effects of impulse noise on the operation of a microprocessor-controlled Loran-C receiver are reduced by muting or attenuating the received signals in the front end of the receiver ahead of the receiver gain during a time period which preceeds the start time of the pulses being tracked. The attenuation is selectively removed after the start time of each pulse being tracked to permit the receiver to perform its time difference of pulse arrival measurements in the normal manner. The attenuation is also selectively removed during those time periods in which the receiver performs its envelope slope, skywave/groundwave and other such samplings. The attenuation is provided by a muting circuit which is controlled by a time gate signal that derives from the microprocessor of the receiver.

A Novel Algorithm of Image Enhancement Based on Pulse Coupled Neural Network Time Matrix and Rough Set

Abstract: This paper describes a novel algorithm of image enhancement based on pulse coupled neural network (PCNN) time matrix and rough set indiscernibility relation. Firstly, detect image noise using PCNN time matrix, and then partition the original image into three sub-images according to intensity attribute and noise attribute. Secondly, denoise using filtering methods based upon PCNN. Lastly, complete sub-images and enhance each of them by different methods. For the gray images with many object details in dark regions and badly corrupted by impulse noise, the computer simulations show excellent enhancement effect. Namely, noise can be reduced efficiently, object details can be enhanced better and the image would become clear after it is processed by this algorithm. Moreover, the effect of this algorithm is better than that of traditional image enhancement algorithm.

Noise blanking arrangement to minimize blanker splatter

Abstract: Method and apparatus are provided for impulse noise blanking in a radio receiver wherein blanking attenuators are provided in both the wideband, prefilter stage and narrowband, postfilter stage of the receiver so that the bandwidth and location in the receiver in which blanking is provided is optimized dependent upon signal conditions.

Time-diversity permutation coding scheme for narrow-band power-line channels

Abstract: An M-FSK modulation and time-diversity permutation coding scheme for narrow-band power-line communications combined with the soft-decision technique is investigated in this paper. A process to identify the errors caused by impulse noise and narrow-band interference, and to mitigate the error effects is proposed. We further present a permutation decoding algorithm and a majority-logic decoding process to correct the remaining additive errors. Due to its simplicity and low encoding/decoding complexities, this scheme therefore can be suitable for a simple but robust narrow-band power-line communications system of practical interest.