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This paper presents an introduction concerning landmines contamination issues, crisis, legacy, and action. We conduct an analysis of mine action, national and international programs. Before proposing the usage on early innovations, it is consequential to survey the foundation of the mine activity area since its start. We introduce the problems of landmines and how action is taken to face these problems...
Managing photos over the Internet is an increasingly bigger problem with sizeable social and financial implications. More than 1 billion Facebook users upload in excess of 350 millions of new pictures per day and 250 billions overall, not to mention other social media sites such as Flickr, Instagram, Google+, Tumblr and Pinterest, and these figures are growing steadily. It is hence not surprising...
Embeddings provide compact representations of signals to be used to perform inference in a wide variety of tasks. Random projections have been extensively used to preserve Euclidean distances or inner products of high dimensional signals into low dimensional representations. Different techniques based on hashing have been used in the past to embed set similarity metrics such as the Jaccard coefficient...
In this paper, we propose a method for estimating the sparsity of a signal from its noisy linear projections without recovering it. The method exploits the property that linear projections acquired using a sparse sensing matrix are distributed according to a mixture distribution whose parameters depend on the signal sparsity. Due to the complexity of the exact mixture model, we introduce an approximate...
In this study we have developed a supervised learning to automatically detect with high accuracy EEG reports that describe seizures and epileptiform discharges. We manually labeled 3,277 documents as describing one or more seizures vs no seizures, and as describing epileptiform discharges vs no epileptiform discharges. We then used Naïve Bayes to develop a system able to automatically classify EEG...
When image authenticity verification has to be carried out without any knowledge about the possible processing undergone by the image under analysis, it is fundamental to rely on a multi-clue approach, that merges the information stemming from several complementary forensic tools. This paper introduces a fully automatic framework for fusing the maps created by a set of unsupervised forgery localization...
In this paper, we analyze the security of compressed sensing (CS) defined over finite fields. First, we prove that acquiring signals using dense sensing matrices may provide almost perfect secrecy. Then, we prove that using sparse sensing matrices, which admit efficient recovery algorithms mutuated by coding theory, reveals information only on the sparsity of the sensed signal, and that such information...
Recent results have shown that the compressed sensing (CS) framework can provide a form of data confidentiality when the signals are sensed by a fully random matrix. In this paper, we extend those results by considering the security achievable by partially circulant sensing matrices generated from a vector of random variables. Circulant matrices, having similar CS recovery performance as fully random...
We propose a method for detecting insertion and deletion of whole frames in digital videos. We start by strengthening and extending a state of the art method for double encoding detection, and propose a system that is able to locate the point in time where frames have been deleted or inserted, discerning between the two cases. The proposed method is applicable even when different codecs are used for...
A comparison between two forensic techniques for the reverse engineering of a chain composed by a double JPEG compression interleaved by a linear contrast enhancement is presented here. The first approach is based on the well known peak-to-valley behavior of the histogram of double-quantized DCT coefficients, while the second approach is based on the distribution of the first digit of DCT coefficients...
This work addresses forgery localization in MPEG-2 compressed videos. The proposed method is based on the analysis of Double Quantization (DQ) traces in frames that were encoded twice as intra (i.e., I-frames). Employing a state-of-the-art method, such frames are located in the video under analysis by estimating the size of the Group Of Pictures (GOP) that was used in the first compression; then,...
Video forensics is an emerging discipline, that aims at inferring information about the processing history undergone by a digital video in a blind fashion. In this work we introduce a new forensic footprint and, based on it, propose a method for detecting whether a video has been encoded twice; if this is the case, we also estimate the size of the Group Of Pictures (GOP) employed during the first...
This paper describes the most recent achievements in speckle reduction of COSMO-SkyMed (CSKê) synthetic aperture radar (SAR) data. An advanced multresolution despeckling filter, based on undecimated wavelet transform (UDWT) and maximum a-posteriori (MAP) estimation has been specialized and optimized to CSKê data, both single- and multi-look. The tradeoff between performances...
In this work a decision fusion strategy for image forensics is presented, based on Dempster-Shafer's Theory of Evidence. The goal is to automatically summarize the information provided by several image forensics tools, allowing both a binary and a soft interpretation of the global output produced. The proposed strategy is easily extendable to an arbitrary number of tools, it does not require that...
In this paper, we present a forensic algorithm to discriminate between original and forged regions in JPEG images, under the hypothesis that the tampered image presents a non-aligned double JPEG compression (NA-JPEG). Unlike previous approaches, the proposed algorithm does not need to manually select a suspect region to test the presence or the absence of NA-JPEG artifacts. Based on a new statistical...
We present a novel, automatic point-process approach that is able to provide continuous, instantaneous estimates of heart rate variability (HRV) and respiratory sinus arrhythmia (RSA) in long duration data recordings such as those during an entire night of sleep. We analyze subjects with and without sleep apnea who underwent diagnostic polysomnography. The proposed algorithm is able to quantify multi-scale...
The privacy protection of the biometric data is an important research topic, especially in the case of distributed biometric systems. In this scenario, it is very important to guarantee that biometric data cannot be steeled by anyone, and that the biometric clients are unable to gather any information different from the single user verification/identification. In a biométrie system with high level...
In this paper, we address the problem of FingerCode-based identity matching using encrypted templates. Instead of the classical approach of combining secure signal processing (SSP) tools to mimic the behavior of some well-known identity matching algorithm, we will investigate the possibility of using a SSP-friendly biometric implementation, i.e., an implementation based on SSP tools. We will propose...
In this work, maximum a posteriori (MAP) despeckling, implemented in the multiresolution domain defined by the undecimated discrete wavelet transform (UDWT), will carried out on very high resolution (VHR) SAR images and compared with earlier multiresolution approaches developed by the authors. The MAP solution in UDWT domain has been specialized to SAR imagery. Every UDWT subband is segmented into...
Buyer-seller watermarking (BSW) protocols allow copyright protection of digital content. The protocol is anonymous when the identity of buyers is not revealed if they do not release pirated copies. Existing BSW protocols are not provided with a formal analysis of their security properties. We employ the ideal-world/real-world paradigm to propose a formal security definition for copyright protection...
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