Tracking HOG Descriptors for Gesture Recognition

International audienceWe introduce a new HoG (Histogram of Oriented Gradients) tracker for Gesture Recognition. Our main contribution is to build HoG trajectory descriptors (representing local motion) which are used for gesture recognition. First, we select for each individual in the scene a set of corner points to determine textured regions where to compute 2D HoG descriptors. Second, we track these 2D HoG descriptors in order to build temporal HoG descriptors. Lost descriptors are replaced by newly detected ones. Finally, we extract the local motion descriptors to learn offline a set of given gestures. Then, a new video can be classified according to the gesture occurring in the video. Results shows that the tracker performs well compared to KLT tracker [1]. The generated local motion descriptors are validated through gesture learning-classification using the KTH action database [2]

Gesture Recognition by Learning Local Motion Signatures

International audienceThis paper overviews a new gesture recognition framework based on learning local motion signatures (LMSs) introduced by [5]. After the generation of these LMSs computed on one individual by tracking Histograms of Oriented Gradient (HOG) [2] descriptor, we learn a codebook of video-words (i.e. clusters of LMSs) using k-means algorithm on a learning gesture video database. Then the videowords are compacted to a codebook of code-words by the Maximization of Mutual Information (MMI) algorithm. At the final step, we compare the LMSs generated for a new gesture w.r.t. the learned codebook via the k-nearest neighbors (k-NN) algorithm and a novel voting strategy. Our main contribution is the handling of the N to N mapping between code-words and gesture labels with the proposed voting strategy. Experiments have been carried out on two public gesture databases: KTH [16] and IXMAS [19]. Results show that the proposed method outperforms recent state-of-the-art methods

Recognizing Gestures by Learning Local Motion Signatures of HOG Descriptors

International audienceWe introduce a new gesture recognition framework based on learning local motion signatures (LMSs) of HOG descriptors . Our main contribution is to propose a new probabilistic learning-classification scheme based on a reliable tracking of local features. After the generation of these LMSs computed on one individual by tracking Histograms of Oriented Gradient (HOG) descriptor, we learn a code-book of video-words (i.e. clusters of LMSs) using kmeans algorithm on a learning gesture video database. Then the video-words are compacted to a code-book of code-words by the Maximization of Mutual Information (MMI) algorithm. At the final step, we compare the LMSs generated for a new gesture w.r.t. the learned code-book via the k-nearest neighbors (k-NN) algorithm and a novel voting strategy. Our main contribution is the handling of the N to N mapping between code-words and gesture labels within the proposed voting strategy. Experiments have been carried out on two public gesture databases: KTH and IXMAS . Results show that the proposed method outperforms recent state-of-the-art method

PolyOrBAC: a security framework for critical infrastructures

International audienceDue to physical and logical vulnerabilities, a critical infrastructure (CI) can encounter failures of various degrees of severity, and since there are many interdependencies between CIs, simple failures can have dramatic consequences on the users. In this paper, we mainly focus on malicious threats that might affect the information and communication system that controls the Critical Infrastructure, i.e., the Critical Information Infrastructure (CII). To address the security challenges that are specific of CIIs, we propose a collaborative access control framework called PolyOrBAC. This approach offers each organization taking part in the CII the capacity of collaborating with the other ones, while maintaining a control on its resources and on its internal security policy. The interactions between organizations participating in the CII are implemented through web services (WS), and for each WS a contract is signed between the service-provider organization and the service-user organization. The contract describes the WS functions and parameters, the liability of each party and the security rules controlling the interactions. At runtime, the compliance of all interactions with these security rules is checked. Every deviation from the signed contracts triggers an alarm, the concerned parties are notified and audits can be used as evidence for sanctioning the party responsible for the deviation. Our approach is illustrated by a practical scenario, based on real emergency actions in an electric power grid infrastructure, and a simulation test bed has been implemented to animate this scenario and experiment with its security issues

Lessons Learned from the deployment of a high-interaction honeypot

This paper presents an experimental study and the lessons learned from the observation of the attackers when logged on a compromised machine. The results are based on a six months period during which a controlled experiment has been run with a high interaction honeypot. We correlate our findings with those obtained with a worldwide distributed system of lowinteraction honeypots

MULTIPLE OBJECT TRACKING WITH OCCLUSIONS USING HOG DESCRIPTORS AND MULTI RESOLUTION IMAGES

International audienceWe present an algorithm for tracking multiple objects through occlusions. Firstly, for each detected object we compute feature points using the FAST algorithm [1]. Secondly, for each feature point we build a descriptor based on the Histogram of Oriented Gradients (HOG) [2]. Thirdly, we track feature points using these descriptors. Object tracking is possible even if objects are occluded. If few objects are merged and detected as a single one, we assign each newly detected feature point in such single object to one of these occluded objects. We apply probabilistic methods for this task, using information from the previous frames like object size and motion (speed and orientation). We use multi resolution images to decrease the processing time. Our approach is tested on the synthetic video sequence, the KTH dataset [3] and the CAVIAR dataset [4]. All tests confirm the effectiveness of our approach

Experimental Validation of Architectural Solutions

This is a interim report on the experimental validation of architectural solutions performed in WP5 of project CRUTIAL. The two main contributions are the description of an attack injection tool for testing the architectural solutions and the description of a monitor and data collector that collects and analyses information about the behavior of the software after it has been attacke

Resilience-Building Technologies: State of Knowledge -- ReSIST NoE Deliverable D12

This document is the first product of work package WP2, "Resilience-building and -scaling technologies", in the programme of jointly executed research (JER) of the ReSIST Network of Excellenc

Use case scenarios and preliminary reference model

This document provides the starting point for the development of dependability solutions in the HIDENETS project with the following contents: (1) A conceptual framework is defined that contains the relevant terminology, threats and general requirements. This framework is a HIDENETS relevant subset of existing state-of-the-art views in the scientific dependability community. Furthermore, the dependability framework contains a first list of relevant functionalities in the communication and middleware level, which will act as input for the architectural discussions in HIDENETS work packages (WPs) 2 and 3. (2) A set of 17 applications with HIDENETS relevance is identified and their corresponding dependability requirements are derived. These applications belong mostly to the class of car-tocar and car-to-infrastructure services and have been selected due to their different types of dependability needs. (3) The applications have been grouped in six HIDENETS use cases, each consisting of a set of applications. The use cases will be the basis for the development of the dependability solutions in all other WPs. Together with a description of each use-case, application-specific architectural aspects are identified and corresponding failure modes and challenges are listed. (4) The business impact of dependability solutions for these use cases is analysed. (5) A preliminary definition of a HIDENETS reference model is provided, which contains highlevel architectural assumptions. This HIDENETS reference model will be further developed in the course of the HIDENETS projects in close cooperation with the other WPs, which is the reason why the preliminary version also contains a collection of potential contributions from other WPs that shall be developed and investigated in the course of the HIDENETS project. In summary, the identified use-cases and their requirements clearly show the large number of dependability related challenges. First steps towards technical solutions have been made in this report in the preliminary reference model, whereas the other work-packages have started in the meanwhile to develop such solutions further based on 'middleware technology' (WP2), 'communication protocols' (WP3), 'quantitative analysis methodology' (WP4), and 'design and testing methodology' (WP5