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Related papers: Guided patch-wise nonlocal SAR despeckling

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This paper presents a technique for reducing speckle in Polarimetric Synthetic Aperture Radar (PolSAR) imagery using Nonlocal Means and a statistical test based on stochastic divergences. The main objective is to select homogeneous pixels…

Information Theory · Computer Science 2013-04-18 Leonardo Torres , Sidnei J. S. Sant'Anna , Corina C. Freitas , Alejandro C. Frery

The wavelet shrinkage denoising approach is able to maintain local regularity of a signal while suppressing noise. However, the conventional wavelet shrinkage based methods are not time-scale adaptive to track the local time-scale…

Computer Vision and Pattern Recognition · Computer Science 2016-08-03 Mario Mastriani , Alberto E. Giraldez

In Synthetic Aperture Radar (SAR) imaging, despeckling is very important for image analysis,whereas speckle is known as a kind of multiplicative noise caused by the coherent imaging system. During the past three decades, various algorithms…

Image and Video Processing · Electrical Eng. & Systems 2020-12-01 Qianqian Zhang , Ruizhi Sun

Speckle reduction is a key step in many remote sensing applications. By strongly affecting synthetic aperture radar (SAR) images, it makes them difficult to analyse. Due to the difficulty to model the spatial correlation of speckle, a deep…

Image and Video Processing · Electrical Eng. & Systems 2021-04-14 Emanuele Dalsasso , Loïc Denis , Florence Tupin

Speckle noise, inherent in synthetic aperture radar (SAR) images, degrades the performance of the various SAR image analysis tasks. Thus, speckle noise reduction is a critical preprocessing step for smoothing homogeneous regions while…

Computer Vision and Pattern Recognition · Computer Science 2018-01-16 Fatih Nar

Synthetic Aperture Radar (SAR) despeckling is an important problem in remote sensing as speckle degrades SAR images, affecting downstream tasks like detection and segmentation. Recent studies show that convolutional neural networks(CNNs)…

Computer Vision and Pattern Recognition · Computer Science 2022-06-01 Malsha V. Perera , Wele Gedara Chaminda Bandara , Jeya Maria Jose Valanarasu , Vishal M. Patel

In this paper, a new probability density function (pdf) is proposed to model the statistics of wavelet coefficients, and a simple Kalman's filter is derived from the new pdf using Bayesian estimation theory. Specifically, we decompose the…

Computer Vision and Pattern Recognition · Computer Science 2016-08-03 Mario Mastriani , Alberto E. Giraldez

In this letter, we aim to address a synthetic aperture radar (SAR) despeckling problem with the necessity of neither clean (speckle-free) SAR images nor independent speckled image pairs from the same scene, and a practical solution for SAR…

Image and Video Processing · Electrical Eng. & Systems 2021-01-19 Ye Yuan , Jian Guan , Pengming Feng , Yanxia Wu

The segmentation of synthetic aperture radar (SAR) images is a longstanding yet challenging task, not only because of the presence of speckle, but also due to the variations of surface backscattering properties in the images. Tremendous…

Computer Vision and Pattern Recognition · Computer Science 2017-07-25 Gui-Song Xia , Gang Liu , Wen Yang

Optical image data have been used by the Remote Sensing workforce to study land use and cover since such data is easily interpretable. Synthetic Aperture Radar (SAR) has the characteristic of obtaining images during all-day, all-weather and…

Image and Video Processing · Electrical Eng. & Systems 2021-06-04 Battula Balnarsaiah , G Rajitha

Speckle noise is a fundamental challenge in coherent imaging systems, significantly degrading image quality. Over the past decades, numerous despeckling algorithms have been developed for applications such as Synthetic Aperture Radar (SAR)…

Information Theory · Computer Science 2025-01-31 Ali Zafari , Shirin Jalali

We describe a novel method for removing speckle (in wavelet domain) of unknown variance from SAR images. The me-thod is based on the following procedure: We apply 1) Bidimentional Discrete Wavelet Transform (DWT-2D) to the speckled image,…

Computer Vision and Pattern Recognition · Computer Science 2016-07-13 Mario Mastriani

Deep learning (DL) has proven to be a suitable approach for despeckling synthetic aperture radar (SAR) images. So far, most DL models are trained to reduce speckle that follows a particular distribution, either using simulated noise or a…

Image and Video Processing · Electrical Eng. & Systems 2021-03-15 Adugna G. Mullissa , Diego Marcos , Devis Tuia , Martin Herold , Johannes Reiche

In this paper, we proposed to investigate unsupervised anomaly detection in Synthetic Aperture Radar (SAR) images. Our approach considers anomalies as abnormal patterns that deviate from their surroundings but without any prior knowledge of…

Computer Vision and Pattern Recognition · Computer Science 2022-10-31 Max Muzeau , Chengfang Ren , Sébastien Angelliaume , Mihai Datcu , Jean-Philippe Ovarlez

Synthetic Aperture Radar (SAR) images are widely used in remote sensing due to their all-weather, all-day imaging capabilities. However, SAR images are highly susceptible to noise, particularly speckle noise, caused by the coherent imaging…

Information Theory · Computer Science 2024-12-25 Xuran Hu , Mingzhe Zhu , Djordje Stanković , Zhenpeng Feng , Shouhan Mao , Ljubiša Stanković

SAR images are affected by multiplicative noise that impairs their interpretations. In the last decades several methods for SAR denoising have been proposed and in the last years great attention has moved towards deep learning based…

Image and Video Processing · Electrical Eng. & Systems 2020-06-18 Sergio Vitale , Giampaolo Ferraioli , Vito Pascazio

Synthetic Aperture Radar (SAR) images are inherently corrupted by speckle noise, limiting their utility in high-precision applications. While deep learning methods have shown promise in SAR despeckling, most methods employ a single unified…

Computer Vision and Pattern Recognition · Computer Science 2025-11-11 Ziqing Ma , Chang Yang , Zhichang Guo , Yao Li

We have developed a nonlocal algorithm for estimating polarimetric synthetic aperture radar (PolSAR) covariance matrices on single-look complex (SLC) format resolution. The algorithm is inspired by recent work with guided nonlocal means…

Image and Video Processing · Electrical Eng. & Systems 2022-02-16 Jørgen A. Agersborg , Stian Normann Anfinsen , Jane Uhd Jepsen

Synthetic Aperture Radar (SAR) images contain a huge amount of information, however, the number of practical use-cases is limited due to the presence of speckle noise in them. In recent years, deep learning based techniques have brought…

Image and Video Processing · Electrical Eng. & Systems 2020-04-24 Shrey Dabhi , Kartavya Soni , Utkarsh Patel , Priyanka Sharma , Manojkumar Parmar

The analysis of ocean surface is widely performed using synthetic aperture radar (SAR) imagery as it yields information for wide areas under challenging weather conditions, during day or night, etc. Speckle noise constitutes however the…

Image and Video Processing · Electrical Eng. & Systems 2020-12-15 Oktay Karakuş , Igor Rizaev , Alin Achim