Vol. 68, n° 3-4, March-April 2013
Content available on Springerlink
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 coding – MPEG reconfigurable video coding – MPEG reconfigurable graphic coding – Dynamic compilation – Adaptive decoding – Multimedia application – Dataflow program – Reconfiguration – Scalable execution – Dataflow process network – Dataflow 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
Unifying running-key approach and logistic map to generate enciphering sequences
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.
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.
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.
Cooperative multiband joint detection in cognitive radio networks using artificial immune system
Mansoore Saeedzarandi, Paeiz Azmi
Tarbiat Modares University, Tehran, Iran