Catálogo de publicaciones - libros

The Taverna workbench allows constructing highly complex analyses over life sciences data and computational resources. It provides access over 1000 of bioinformatic services, e.g., analysis algorithms for comparing genome sequences, and facilitates the construction of bioinformatic workflows. These workflows make tacit procedural bioinformatics explicit and as such lend themselves for being used in bioinformatics education. However, until now, no Taverna e-learning service exists. In this paper, we describe how Taverna can be used for learning and the services that need to be integrated in Taverna for that purpose. This includes a digital library of multimedia resources since multimedia, especially visualization, plays an important role in bioinformatics. Equally important is an intelligent educational service that automatically assembles learning activities and resources into a pedagogically coherent whole.

A new challenge to data visualization has arisen from a new laboratory technique that is capable of imaging a large number of biomedical relevant molecule types in a single tissue probe, termed the Toponome. While aiming at deciphering the biochemical interactions of the molecules, and thus their biological functions as well their roles in diseases, no current methods of image analysis are fully suited for this new quality of high-dimensional image data. To overcome this problem we demonstrate a novel framework for interactive real-time visualization, making use of standard graphics acceleration hardware. We show a sample implementation of a threshold-based visualization technique that is connected to the original work of the Toponome authors, improving it by means of fast user interaction.

Time lapse video microscopy routinely produces terabyte sized biological image sequence collections, especially in high throughput environments, for unraveling cellular mechanisms, screening biomarkers, drug discovery, image-based bioinformatics, etc. Quantitative movement analysis of tissues, cells, organelles or molecules is one of the fundamental signals of biological importance. The accurate detection and segmentation of moving biological objects that are similar but is the focus of this paper. The problem domain shares similarities with multimedia video analytics. The grayscale structure tensor fails to disambiguate between stationary and moving features without computing dense velocity fields (i.e. optical flow). In this paper we propose a novel motion detection algorithm based on the combined with multi-feature level set-based segmentation, using an efficient additive operator splitting (AOS) numerical implementation, that robustly handles deformable motion of non-homogeneous objects. The flux tensor level set framework effectively handles biological video segmentation in the presence of complex biological processes, background noise and clutter.

Biomedicine is a very rich field of multimedia information. It is also a fruitful ground for information fusion and integration about scientific research data as well as clinical records of digital medical systems. In this paper, we present a global overview of these ideas, which have not been realized so far and could be interesting to the multimedia research community. We exemplify the complex information resources in terms of Gene Ontology (GO), Clinical Bioinformatics Ontology (CBO) and the Foundational Model of Anatomy (FMA). GO is a biomedical scientific research system used to describe genes and gene products, but no cellular components. CBO is a clinical oriented ontology of information, which potentially include many multimedia images: X-Ray, ultrasound and magnetic resonance images. FMA is a foundational clinical source used to describe the anatomy of the human body as well as cellular components. While scientists in each sector may use these systems to help develop their own information, it is very difficult for a layman or broad-spectrum researcher to integrate the two different languages into one interface. We will attempt to address these issues to describe how information fusion can be achieved.

Orthogonal Frequency Division Multiplexing (OFDM) is a promising technique in broadband wireless communication systems. This paper presents a novel multi-reference scheme based on 3D interleaving for video coding and transmission over OFDM channel. Initially, a combining interleaving method in spatial, frequency and temporal domains, called SFTI, is proposed. With SFTI, different slices within one frame are transmitted in different sub-channels of OFDM, whose SNR can be estimated, and the transmission status of slices through these sub-channels are real-time feedback to the encoder. Based on the feedback information, a multi-reference scheme for video coding is proposed where the well-transmitted slices are selected as the reference picture of its consequent pictures in inter-frame coding to eliminate the impairment caused by error propagation in video transmission over wireless OFDM channels. Extensive experimental results have demonstrated the effectiveness of the proposed methods in error resilience.

As is well known, in video applications the former P frames are more important than the subsequent P frames in coding/decoding order due to the inter-prediction architecture adopted by the advanced video coding standards. A source marking mechanism based on this fact is proposed accordingly in this paper, along with an improved two rate three color maker (ITRTCM) scheme, which takes into account both the source mark value of a packet and the current network status. The results of ITRTCM are compared with those of the two rate three color marker (TRTCM), the enhanced token bucket three color marker (ETBTCM) and the TypeMapping method.

The integration of scalable video representation and network coding (NC) offers an excellent solution to robust and flexible video multicast over IP networks. In this work, we examine one critical component in this system, video priority ordering and packetization at the source of the multicast tree. First, a GOP-adaptive layer-based packet priority ordering algorithm is proposed to allow flexible prioritized video transmission with unequal error protection. Then, a packetization scheme tailored to NC delivery is discussed. Simulation results are given to demonstrate that the proposed algorithms offer better performance in video quality and bandwidth efficiency as compared the SNR-based packetization method.

In this paper, we propose an algorithm for INTRA-frame losses over packet loss channels. The novelty is that not only the INTRA-frame but also the subsequent INTER-frames are error concealed. We use the received INTRA-MBs to refine their neighbors based on the strong correlation between adjacent pixel values. In addition, is used to reconstruct the INTER-pixel which has an INTRA-pixel in its motion trajectory. Both subjective and objective simulation results are given to demonstrate the performance of our proposed algorithm.

In this paper, audio data-hiding schemes and speaker/recorder devices are employed to deliver information within nearby areas where connection and networking capabilities are expensive or even unavailable. Conventionally, information delivery in this way suffers from low data rate, questionable robustness and, most seriously, the limited transmission distance. Here, we alleviate the constraint of short transmission distance by devising a novel application scenario where widely available speaker/recorder devices move around together with the recipient – the information delivery service based on car radio systems. To be more specific, passengers in cars can receive additional visual information broadcasted through radio channels using devices capable of audio recording. To achieve sufficient data rate and necessary robustness, existing audio watermarking schemes have been enhanced. Furthermore, empirical on-road tests are performed to evaluate the robustness of the proposed scheme in real-world environments. According to our experimental results, enhanced audio watermarking schemes can be practically adopted to provide visual information without introducing additional costs or specific receivers in the client end. The proposed scheme can bring new business opportunities and commercial values for existing radio channels and car radio systems.

Within an MPEG-21 architecture, the two key concepts are the Digital Item, representing multimedia content, and Users, interacting with this content. MPEG-21 introduced Digital Item Processing to allow content authors to describe suggested processing of their Digital Items. It standardizes ways to insert functionality into a Digital Item, as such, creating a dynamic and interactive multimedia format. Moreover, if a terminal wants to support Digital Item Processing, it needs to provide an execution environment offering basic functionality. The semantics of this functionality have been standardized, however there is significant room for interpretation. Consequently, a Digital Item author may not be aware of the actual processing when using this functionality. In this paper, a system is proposed, compliant with the Digital Item Processing specification, to give content creators full control on the processing. This allows creating advanced predictable multimedia systems in an MPEG-21 environment.