Special issue: Networked digital media

Vol. 68, n° 3-4, March-April 2013
Content available on Springerlink

Guest editors
Mihai Mitrea, Télécom SudParis, France
Françoise Prêteux, Mines ParisTech, France
Touradj Ebrahimi, EPFL, Switzerland
Giovanna Carofiglio, Alcatel-Lucent Bell Labs, France


Mihai Mitrea, Françoise Prêteux, Touradj Ebrahimi, Giovanna Carofiglio

Quality user experience in advanced IP video services

António Pedro Inácio1, Rui Santos Cruz2, Mário Serafim Nunes2
1 Instituto Superior Técnico, Portugal Telecom, Lisboa, Portugal
2 INESC-ID, Instituto Superiotr Técnico, Lisboa, Portugal

Abstract The continuous improvement in the delivery of advanced video services, along with evolved technical conditions at the client side, contributed to the appearance of new methods for the evaluation of quality of service (QoS) and quality of experience (QoE) from the user’s point of view. This article describes the development of a model that correlates QoS parameters and QoE factors with impact on the variation of the user’s perception of the quality. A quality assessment test was performed with 40 participants that ranked more than 140 videos. The detailed analysis of the collected data from the test allowed to conclude that all the considered factors had significant impact on the perceived quality. Those factors were aggregated in a single model using linear regression techniques to join their behavior and associate adequate weights to each factor. The results from validity tests of the model were encouraging, achieving 99 % of accuracy. This model can be considered a new no-reference metric to infer the perceived quality, applicable in many contexts, but essentially as a tool for service providers to estimate the rank customers may give to a content.

Keywords Quality of Service – Quality of Experience – Quality of Perception – Multimedia streaming.

Optimized dynamic compilation of dataflow representations for multimedia applications

Jérôme Gorin1, Mickaël Raulet2, Françoise Prêteux3  
1 Télécom SudParis, Institut Mines-Télécom, Evry, France
2 IETR, INSA Rennes, France
3 Mines ParisTech, Institut Mines-Télécom, France

Abstract This paper proposes two optimization methods based on dataflow representations and dynamic compilation that enhance flexibility and performance of multimedia applications. These optimization methods are intended to be used in an adaptive decoding context, or, in other terms, where decoders have the ability to adapt their decoding processes according to a bitstream. This adaptation is made possible by coupling the decoding information to process a stream inside a coded stream. In this paper, we use dataflow representations from the upcoming MPEG Reconfigurable Media Coding (RMC) standard to supply the decoding information to adaptive decoders. The benefits claimed by MPEG RMC are a reuse of coding tools between different specifications of decoder and an execution scalability on different processing units with a single specification, which can target either hardware and/or software platforms. These benefits are not yet achievable in practice as these specifications are not used at the receiver side in MPEG RMC. We valid these benefits and propose two optimizations for the generation and the execution of dataflow models: the first optimization takes benefits of the reuse of coding tools to reduce the time to obtain—configure—enforceable decoders. The second provides an efficient, dynamic, and scalable execution according to the features of the execution platform. We show the practical impact of these two optimizations on two decoder representations compliant with the MPEG-4 part 2 Simple Profile standard and the MPEG-4 Advanced Video Coding standard. The results shows that configuration time can be reduced by 3 and the performance of decoders can be increased by 50 %.

Keywords MPEG reconfigurable media codingMPEG reconfigurable video codingMPEG reconfigurable graphic codingDynamic compilationAdaptive decodingMultimedia applicationDataflow programReconfigurationScalable executionDataflow process networkDataflow scheduling.

Multi-criteria decision algorithms for efficient content delivery in content networks

Andrzej Bęben1, Jordi Mongay Batalla1, Wei Koong Chai2, Jarosław Śliwiński1
1 Warsaw University of Technology, Warsaw, Poland
2 University College London, London, UK

Abstract Today’s Internet is prominently used for content distribution. Various platforms such as content delivery networks (CDNs) have become an integral part of the digital content ecosystem. Most recently, the information-centric networking (ICN) paradigm proposes the adoption of native content naming for secure and efficient content delivery. This further enhances the flexibility of content access where a content request can be served by any source within the Internet. In this paper, we propose and evaluate a multi-criteria decision algorithm for efficient content delivery applicable for content networks in general (among others, CDN and ICN). Our algorithm computes the best available source and path for serving content requests taking into account information about content transfer requirements, location of the consumer, location of available content servers, content server load and content delivery paths between content servers and consumer. The proposed algorithm exploits two closely related processes. The first level discovers multiple content delivery paths and gathers their respective transfer characteristics. This discovery process is based on long-term network measurements and performed offline. The second process is invoked for each content request to find the best combined content server and delivery path. The cooperation between both levels allows our algorithm to increase the number of satisfied content requests thanks to efficient utilisation of network and server resources. The proposed decision algorithm was evaluated by simulation using Internet scale network model. The results confirm the effectiveness gain of content network architectures that introduce network awareness. Moreover, the simulation process allows for a comparison between different routing algorithms and, especially, between single and multipath routing algorithms.

Keywords Multi-criteria decision algorithms – Content networks – Future internet.

Internet-scale content mediation in information-centric networks

George Pavlou1, Ning Wang2, Wei Koong Chai1, Ioannis Psaras1
1 University College London, UK
2 University of Surrey, UK

Abstract Given that the vast majority of Internet interactions relate to content access and delivery, recent research has pointed to a potential paradigm shift from the current host-centric Internet model to an information-centric one. In information-centric networks, named content is accessed directly, with the best content copy delivered to the requesting user given content caching within the network. Here, we present an Internet-scale mediation approach for content access and delivery that supports content and network mediation. Content characteristics, server load, and network distance are taken into account in order to locate the best content copy and optimize network utilization while maximizing the user quality of experience. The content mediation infrastructure is provided by Internet service providers in a cooperative fashion, with both decoupled/two-phase and coupled/one-phase modes of operation. We present in detail the coupled mode of operation which is used for popular content and follows a domain-level hop-by-hop content resolution approach to optimally identify the best content copy. We also discuss key aspects of our content mediation approach, including incremental deployment issues and scalability. While presenting our approach, we also take the opportunity to explain key information-centric networking concepts.
Keywords Information-centric networkingContent mediationServer selection.

Unifying running-key approach and logistic map to generate enciphering sequences

Adriana Vlad1,2, Azeem Ilyas1, Adrian Luca1
1 Politehnica University of Bucharest, Romania
2 Romanian Academy, Bucharest, Romania
Abstract The paper presents a new approach to generating enciphering sequences useful in information protection, with an illustration on images. The procedure is both theoretically and experimentally supported by combining elements derived from the running-key cipher, information theory and statistics. The enciphering key generator is based on the logistic map, and its theoretical properties are demonstrated by statistical tests. The new enciphering sequences comply with the fair coin model, and the randomly chosen initial conditions of the logistic map (defining the enciphering sequence) can be part of the secret key. Although dealing with a particular case of chaotic system, the paper contains the necessary elements so that the overall procedure can be applied to other chaotic maps (e.g., tent map).
Keywords Logistic map Running-key cipher Statistical independence Chaotic binary enciphering sequences Image encryption Type II statistical error probability

Cinematography sequences tracking by means of fingerprinting techniques

Adriana Garboan1, Mihai Mitrea1, Françoise Prêteux2
1 Télécom SudParis, Institut Mines-Télécom, France
2 Mines ParisTech, Institut Mines-Télécom, France

Abstract Video fingerprints are short features extracted from a video sequence in order to uniquely identify its visual content and its replicas. By advancing a new robust fingerprinting method, the present paper takes the challenge of designing an enabler for the use of Internet as a distribution tool in cinematography. In this respect, a 2D-DWT-based robust video fingerprinting method is designed so as to address two use cases, namely the retrieval of video content from a database and the tracking of in-theater camcorder recorded video content. A set of largest absolute value wavelet coefficients is considered as the fingerprint and a repeated statistical test is used as the matching procedure. The video dataset consists of two corpora, one for each use case. The first corpus regroups 3 h of heterogeneous original content (organized under the framework of the HD3D-IIO French national project) and of its attacked versions (a total of 21 h of video content). The second corpus consists of 3 h of heterogeneous content (i.e., HD3D-IIO corpus) and of 1 h of live camcorder recorded video content (a total of 4 h of video content). The inner 2D-DWT properties with respect to content-preserving attacks (such as linear filtering, sharpening, geometric, conversion to grayscale, small rotations, contrast changes, brightness changes, and live camcorder recording) ensure the following results: in the first use case, the probability of false alarm and missed detection are lower than 0.0005, precision and recall are higher than 0.97; in the second use case, the probability of false alarm is 0.00009, the probability of missed detection is lower than 0.0036, precision and recall are equal to 0.72.

Keywords Robust video fingerprinting – DWT – Robustness – Uniqueness – Live camcorder recording

Feed and fly control of visual scanpaths for foveation image processing

Giuseppe Boccignone1, Mario Ferraro2
1 Universitá di Milano, Italy
2 Universitá di Torino, Italy

Abstract Foveation-based processing and communication systems can exploit a more efficient representation of images and videos by removing or reducing visual information redundancy, provided that the sequence of foveation points, the visual scanpath, can be determined. However, one point that is neglected by the great majority of foveation models is the “noisy” variation of the random visual exploration exhibited by different observers when viewing the same scene, or even by the same subject along different trials. Here, a model for the generation and control of scanpaths that accounts for such issue is presented. In the model, the sequence of fixations and gaze shifts is controlled by a saliency-based, information foraging mechanism implemented through a dynamical system switching between two states, “feed” and “fly.” Results of the simulations are compared with experimental data derived from publicly available datasets.

Keywords Eye movementsRandom walkVisual attentionImage encoding

A robust invariant bipolar representation for R3 surfaces: applied to the face description

Faouzi Ghorbel, Majdi Jribi
La Manouba University, Tunisia

Abstract In this paper, we intend to introduce a novel invariant curved surface representation under the 3D motion group. It is constructed from the superposition of the two geodesic potentials generated from a given couple of surface points. By sampling this continuous representation, invariant points are extracted from a large neighborhood around these reference points. Different numerical methods are implemented in order to find an efficient approximation in the mean of the shape distance. The inference of small distortions of points positions applied to the reference points is analyzed. We apply the proposed representation to real 3D images. The experimentations are performed on the 3D facial database Bosphorus.

Keywords Bipolar surface representation – Geodesic potentialInvariant3D mesh – Hausdorff distanceFace analysisRobustnessShape space

Open topics

Efficient ID-based multiproxy multisignature without bilinear maps in ROM

Namita Tiwari1 , Sahadeo Padhye1, and Debiao He2
1 Motilal Nehru National Institute of Technology, Allahabad, India
2 Wuhan University, China

Abstract Most of the previously proposed identity-based multiproxy multisignature (IBMPMS) schemes used pairings in their construction. But pairing is regarded as an expensive cryptographic primitive in terms of complexity. The relative computation cost of a pairing is approximately more than ten times of the scalar multiplication over elliptic curve group. So, to reduce running time, we first define a model of a secure MPMS scheme, then propose an IBMPMS scheme without using pairings. We also prove the security of our scheme against chosen message attack in random oracle model. Our scheme’s construction avoids bilinear pairing operations but still provides signature in the ID-based setting and reduces running time heavily. Therefore, proposed scheme is more applicable than previous schemes in terms of computational efficiency for practical applications.

Keywords Digital signature Identity-based cryptography – Multiproxy multisignature – Elliptic curve discrete log problem – Random oracle model

Cooperative multiband joint detection in cognitive radio networks using artificial immune system

Mansoore Saeedzarandi, Paeiz Azmi
Tarbiat Modares University, Tehran, Iran

Abstract In cognitive radio technology, spectrum sensing enables users to sense the environment and find spectrum holes. Cooperative sensing is a good idea for reliable detection of primary users in shadowed environments. In this study, spatial spectral joint detection with some constraints that keep the interference at the primary user below a suitable level is considered as the optimization problem for collaborative sensing. Convex optimization is able to obtain near-optimal solutions because of the non-convexity nature of the optimization problem. In this paper, we use artificial immune system (based on the clonal selection theory) to obtain the optimal solutions without any reformulations or mathematical costs. Numerical results show that our proposed algorithm outperforms the genetic algorithm used in the previous works.
Keywords Cognitive radio networks – Spectrum sensing – Spatial spectral joint detection – Artificial immune system – Clonal selection theory