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Non-local means denoising using an adaptive kernel

Amir Ali Tahmouresi, Saeid Saryazdi, Saeid Reza Seydnejad
2012 20th Iranian Conference on Electrical Engineering (ICEE2012)  
Non-local means algorithm is one of the powerful image denoising methods. Maintaining noise near edges and textural parts of a noisy image, is one of the main drawbacks of NLM.  ...  Experimental results show superiority of our algorithm in comparison with original NLM as well as a method based on shape adaptive patches.  ...  Conclusion In this paper a new adaptive kernel is proposed for non-local means in order to remove residual noise near high contrasted edges of denoised image by NLM.  ... 
doi:10.1109/iraniancee.2012.6292584 fatcat:wx5habyrp5c27j7zh74gjmymqm

Local fractal dimension based approaches for colonic polyp classification

Michael Häfner, Toru Tamaki, Shinji Tanaka, Andreas Uhl, Georg Wimmer, Shigeto Yoshida
2015 Medical Image Analysis  
However, the shape, size and orientation adapted local fractal dimension approaches (which are especially designed to enhance the viewpoint invariance) are in general not more viewpoint invariant than  ...  These extensions additionally extract shape and/or gradient information of the image to enhance the discriminativity of the original approach.  ...  That means for each blob b, a specific filter is generated and its shape and orientation is adapted to the considered blob.  ... 
doi:10.1016/j.media.2015.08.007 pmid:26385078 fatcat:wboxua6cnbcfli3vd7mpoetxbe

An Adaptive Tone Mapping Algorithm for High Dynamic Range Images [chapter]

Jian Zhang, Sei-ichro Kamata
2009 Lecture Notes in Computer Science  
The novelty of our method is that the local details are enhanced according to a non-linear adaptive spatial filter (Gaussian filter), whose shape is adapted to high-contrast edges of the image.  ...  Therefore, the algorithm can preserve visibility and contrast impression of high dynamic range scenes in the common display devices.  ...  Figs.5 (a) and (d) (regions in blue circles) show the difference between using an adaptive filter and a non-adaptive filter (the variance of Gaussian filter is a fixed value).  ... 
doi:10.1007/978-3-642-03265-3_22 fatcat:gxaiwwaqgjd6vdlzedcavtr6li

Image and Video Abstraction by Anisotropic Kuwahara Filtering

Jan Eric Kyprianidis, Henry Kang, Jürgen Döllner
2009 Computer graphics forum (Print)  
It is based on a generalization of the Kuwahara filter that is adapted to the local shape of features, derived from the smoothed structure tensor.  ...  Contrary to conventional edge-preserving filters, our filter generates a painting-like flattening effect along the local feature directions while preserving shape boundaries.  ...  In this work, we present a generalization of the Kuwahara filter that removes clustering artifacts by adapting shape, scale and orientation of the filter to the local structure of the input (Figure 3  ... 
doi:10.1111/j.1467-8659.2009.01574.x fatcat:dbpjsopznfd53dnh6kew5xflca

General Adaptive Neighborhood Image Restoration, Enhancement and Segmentation [chapter]

Johan Debayle, Yann Gavet, Jean-Charles Pinoli
2006 Lecture Notes in Computer Science  
These so-called General Adaptive Neighborhoods (GANs) are simultaneously adaptive with the spatial structures, the analyzing scales and the physical settings of the image to be addressed and/or the human  ...  An intensity image is represented with a set of local neighborhoods defined for each point of the image to be studied.  ...  This (non-adaptive) toggle contrast will be compared with the adaptive LIP toggle contrast, using a 'contrast' criterion.  ... 
doi:10.1007/11867586_3 fatcat:ot7emrkzv5cibgwrhnbd4rxgau

Anisotropic Kuwahara Filtering with Polynomial Weighting Functions [article]

Jan Eric Kyprianidis, Amir Semmo, Henry Kang, Jürgen Döllner
2010 Computer Graphics and Visual Computing  
It is based on a generalization of the Kuwahara filter that is adapted to the local shape of features.  ...  By contrast, our new weighting functions do not require convolution and can be efficiently computed directly during the filtering in real-time.  ...  By adapting shape, scale and orientation of these ellipses to the local structure of the input, artifacts are avoided.  ... 
doi:10.2312/localchapterevents/tpcg/tpcg10/025-030 dblp:conf/tpcg/KyprianidisSKD10 fatcat:lz4553osgjgetnr7ba4hahf4am

Luminance-contrast properties of contour-shape processing revealed through the shape-frequency after-effect

Elena Gheorghiu, Frederick A.A. Kingdom
2006 Vision Research  
We measured SFAEs for adapting and test contours (and edges) that differed in the contrastpolarity, scale (or blur) and magnitude of luminance contrast.  ...  These results suggest that contour shapes are not encoded in the form of a sparse, cartoon-like sketch, as might be presumed by local energy (i.e. non-phase-selective) or form-cue invariant models, but  ...  Acknowledgment This research was supported by a Natural Sciences and Engineering Research Council of Canada (NSERC) Grant # OGP01217130 given to F.K.  ... 
doi:10.1016/j.visres.2006.04.021 pmid:16769101 fatcat:37q7muy3p5fnteihohn4j33cdm

High dynamic range image rendering with a retinex-based adaptive filter

L. Meylan, S. Susstrunk
2006 IEEE Transactions on Image Processing  
The novelties of our method is first to use an adaptive filter, whose shape follows the image high contrast edges, thus reducing halo artifacts common to other methods.  ...  We propose a new method to render high dynamic range images that models global and local adaptation of the human visual system. Our method is based on the centersurround Retinex model.  ...  ACKNOWLEDGMENT We would like to thank Frédo Durand and Raanan Fattal to have made their images available for our comparison.  ... 
doi:10.1109/tip.2006.877312 pmid:16948325 fatcat:xcree4r5k5gh3bowg2waaoolxe

Review of Preprocessing Techniques for Fundus Image Analysis

Shilpa Joshi, P. T. Karule
2017 Advances in Modelling and Analysis B  
On the intensity values of HIS color model, local adaptive contrast techniques result in intensity normalization and contrast enhancement as proposed by Usher et al. [4].  ...  Contrast enhancement of lesions attributes and overall image color saturation in [10]. Adaptive histogram equalization was applied to M band of CMY color space [11].  ...  [32] was applied adaptive local contrast enhancement to sub-image areas using the local mean and standard deviation of intensities for the detection of bright DR areas from fundus images.  ... 
doi:10.18280/ama_b.600306 fatcat:5m4kyfr6qrekvnrx4jlxh3alau

Removing Speckle Noise in Synthetic Aperture Radar Images using Linear Filters

2020 VOLUME-8 ISSUE-10, AUGUST 2019, REGULAR ISSUE  
The examination begins with the linear filtering, non-linear filtering, adaptive filtering, and hybrid filtering.  ...  In this paper, Hybrid filtering is proposed for SAR despeckling, which involves the improved variants of frost, median and mean filters.  ...  For the hybridization the improved variants of mean, median and frost filters, for example, Edge based Adaptive Mean (EAM) filter 33 Local Adaptive Median (LAM) filter 32 and the Adaptive Frost (AF) filter  ... 
doi:10.35940/ijitee.c1084.0193s20 fatcat:kef6vgvvnbemfb36rlt34dzisq

Non-local Methods with Shape-Adaptive Patches (NLM-SAP)

Charles-Alban Deledalle, Vincent Duval, Joseph Salmon
2011 Journal of Mathematical Imaging and Vision  
We propose in this paper an extension of the Non-Local Means (NL-Means) denoising algorithm.  ...  Experimental results show that this algorithm improve the standard NL-Means performance and is close to stateof-the-art methods, both in terms of visual quality and numerical results.  ...  Acknowledgements The authors would like to thanks Jean-François Aujol, Loïc Denis, Yann Gousseau, Erwan Le Pennec and Florence Tupin for their interesting comments and criticisms.  ... 
doi:10.1007/s10851-011-0294-y fatcat:35dv27slvrbcplphwojmc6tdma

Local and global responses of insect motion detectors to the spatial structure of natural scenes

D. C. O'Carroll, P. D. Barnett, K. Nordstrom
2011 Journal of Vision  
Combined with manipulation of size and contrast of the stimulus images, this allowed us to separate spatial integration properties arising from the receptive field, from other local and global non-linearities  ...  Karin Nordström As a consequence of the non-linear correlation mechanism underlying motion detection, the variability in local pattern structure and contrast inherent within natural scenes profoundly influences  ...  The work was funded by ARC (LP 0667744), AFOSR (FA2386-10-1-4114), and VR (2008-2933).  ... 
doi:10.1167/11.14.20 pmid:22201615 fatcat:tymsubl2qrei3khbzauqv75srq

Comparison of prefiltering operators for road network extraction in SAR images

P. Bolon, J. Chanussot, I. Issa, P. Lambert
1999 Proceedings 1999 International Conference on Image Processing (Cat. 99CH36348)  
This study points out the interest of nonlinear adaptive jiltering techniques.  ...  SAR image analysis is a dificult task because of speckle noise and textures and low Signal to Noise Ratios. This paper focuses on the comparison ofjilter performances in terms of road extraction.  ...  Hence, local contrasts are decreased, with respect to the original image, and increasing the contrast thresholds does not yield better results. x original, th=2 anisotropic diffusion, th=3 A adaptive d  ... 
doi:10.1109/icip.1999.823033 dblp:conf/icip/BolonCIL99 fatcat:ltwquziwdbghzfeaqha5ksfnbm

A denoising method forwhole-body low-dose x-ray imageswith adaptable parameter control

Paolo Irrera, Isabelle Bloch, Maurice Delplanque
2013 2013 IEEE 10th International Symposium on Biomedical Imaging  
The suggested algorithm is based on a non local means filter adapted to the statistics of Poisson noise.  ...  A new feature of the method is to locally set the filtering parameters in order to denoise while preserving details in low absorption regions.  ...  POISSON NL-MEANS WITH ADAPTIVE PARAMETER CONTROL Poisson NL means The key idea of NL means is that local is not always synonym of similar.  ... 
doi:10.1109/isbi.2013.6556705 dblp:conf/isbi/IrreraBD13 fatcat:54ctzo2ysfevtgiu3k5ptcydvu

STUDY OF VARIOUS IMAGE DENOISING APPROACHES

Samandeep kaur, sumeet kaur
2016 International Journal of Advanced Research  
[3] describes an efficient approach to represents non local image modeling, estimation of local shape-adaptive anisotropic and principal component analysis (PCA).  ...  Non-Local Means Image Denoising:- Tasdizen et al [7] presents an image denoising approach based on non local means image denoising with principal component analysis (PCA).  ... 
doi:10.21474/ijar01/802 fatcat:tipcng3aw5avlfak7pyyddkhgm
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