Topic
Median filter
About: Median filter is a research topic. Over the lifetime, 12479 publications have been published within this topic receiving 178253 citations.
Papers published on a yearly basis
Papers
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TL;DR: This paper proposes a local difference descriptor with two feature sets to reveal the traces of median filtering, which is more reliable than prior methods to detect tampering involving local median filtering.
Abstract: As a content-preserved image manipulation, median filtering approach has received extensive attention from forensic analyzers. In this paper, we propose a local difference descriptor with two feature sets to reveal the traces of median filtering. The first set of features are fused rotation invariant uniform local binary patterns (LBP), which can quantify the occurrence statistics of micro-features in an image. The second features set is extracted from pixel difference matrix (PDM), which can better describe how pixel values change introduced by median filtering. To validate the effectiveness of the proposed approach, we compare it with the state-of-the-art median filtering detectors in the cases of JPEG compression and low resolution. Experimental results show that our approach outperforms existing detectors. Moreover, our approach is more reliable than prior methods to detect tampering involving local median filtering. HighlightsA local difference descriptor for median filtering detection is proposed.The occurrence statistics of certain micro-features have discrimination capability.The distribution of micro-features is estimated by the histogram of LBP.Local pixel differences can better describe how pixel values change.Joint probability is suitable to describe the behavior of local difference pairs.
38 citations
18 May 2005
TL;DR: In this article, a new multichannel weighted median filter is proposed which can capture the general correlation structure in array signals and process them in an efficient manner, which is further extended onto the complex domain by means of phase coupling.
Abstract: Summary form only given. Multi-channel and multi-spectral signals are often correlated across channels. Moreover, multispectral images have considerable similarity in in-channel correlations. But in array signal processing, due to the existence of multiple frequency components and their phase shifts, in-channel correlations may vary drastically. In this paper, a new multichannel weighted median filter is proposed which can capture the general correlation structure in array signals and process them in an efficient manner. The algorithm is further extended onto the complex domain by means of "phase coupling". The performance of the filter is presented in a three-sensor array processing example.
38 citations
12 May 2008
TL;DR: This paper aims to improve the quality of the enhanced speech signal provided by standard Wiener filtering by controlling the latter via a second filter regarded as a psychoacoustically motivated weighting factor and propound a new speech enhancement technique.
Abstract: This paper deals with musical noise resulting from subtractive type algorithms and especially Wiener filtering. We compare several methods that introduce perceptually motivated modifications of standard Wiener filtering and we propound a new speech enhancement technique. It aims to improve the quality of the enhanced speech signal provided by standard Wiener filtering by controlling the latter via a second filter regarded as a psychoacoustically motivated weighting factor. According to objective measures, the described process results in significant reduction of musical noise.
38 citations
TL;DR: An improved motion-compensated restoration method for color motion picture films deteriorated due to flashing blotches which consists of an improved multiresolution block matching with log-D search, a rank ordered differences-based blotch detection and 3D vector median filtering for interpolation of missing data.
Abstract: In this paper, we propose an improved motion-compensated restoration method for color motion picture films deteriorated due to flashing blotches. The method consists of an improved multiresolution block matching with log-D search, a rank ordered differences-based blotch detection and 3D vector median filtering for interpolation of missing data, and utilizes five consecutive frames. Performance of the method is tested on artificially corrupted image sequences and real motion picture films, and is compared to that of the three-frame-based method which involves similar algorithms except improved motion estimation and blotch detection. The results show that the method efficiently works even in severely blotched and motion regions in image sequences.
38 citations
10 Jul 1995
TL;DR: Three different non linear methods which filter the wrapped phase map for SAR interferometry are compared, the first method is based on a morphological filter, the second one is a modified median filter and the third is amodified mode filter.
Abstract: Phase unwrapping for SAR interferometry is one of the barriers for obtaining an operational interferometric SAR system (InSAR). For filtering the phase one uses mainly a low pass linear filter applied on the complex interferometric image before evaluating the phase. This paper compares three different non linear methods which filter the wrapped phase map. The first method is based on a morphological filter, the second one is a modified median filter and the third is a modified mode filter. All filters are built considering the periodic character of the wrapped phase function. The characteristics of these filtering approaches are compared, and the number of residues are calculated after each filtering step.
38 citations