Boris Rogge

Validating MPEG-21 encapsulated functional metadata

We describe the validation process of a functional metadata document encapsulated in an MPEG-21 digital item. The validation starts with an MPEG-21 digital item containing the functional metadata and ends with a valid functional metadata document or with a list of error codes. Since the W3C schema language does not suffice to validate all relationships within a functional metadata document, a set of extra rules is defined. These rules are implemented through the use of transformations on functional metadata documents. These transformations are implemented using XSLT.

Deinterlacing using fuzzy-based motion detection

Deinterlacing algorithms are used to convert an interlaced video sequence to the progressive scan format. Interlaced video exposes artifacts like line flicker and line crawling and is unsuitable for progressive media. Picture quality can be improved significantly when a proper deinterfacing algorithm is applied. The paper presents a motion adaptive technique based on a fuzzy motion detector. Preliminary experiments show results using this approach.

Timing issues in multimedia formats: review of the principles and comparison of existing formats

In recent years. a large number of new multimedia (MM) formats have been created. It is widely recognized that the life cycle for a MM document consists of three areas. First of all, a document model is needed to model the MM scenario. Secondly, this document model is to be translated into a computer description. Finally, a set of synchronization primitives must be defined in order to be able to present the computer description to the end-user. The contribution of this paper is the definition of an integrated reference model that covers all three areas. For each of the three areas a model is put forward, based on the current state-of-the-art in that area. From these models, a reference model is created consisting of ten rules and a document model. This model is then applied to a number of real-world MM formats (SMIL, QuickTime, RealVideo, Advanced Streaming Format, Shockwave, and MPEG-4). Finally, a comparison is presented showing the results obtained from applying the reference model to the MM formats.

Metadata‐based access to multimedia architectural and historical archive collections: a review

This review is a summary of the state‐of‐the‐art for those who have not been intimately dealing with the evolution of digital archives. At the same time this survey will be a useful resource and starting point for archivists, librarians and technicians, who are becoming involved in institutional digitization projects. It presents a brief overview of what is meant by a digital library and a digital archive, and how archival collections can be described. It expresses briefly the different approaches to collections and their descriptions and suggests that a consistent approach to descriptions at collection and item level is an important factor in initiatives which seek to provide integrated access to distributed resources, whether those resources are traditional or digital.

Dynamic adaptation of multimedia data for mobile applications

The current explosive expansion of mobile communication systems will lead to an increased demand for multimedia applications. However, due to the large variety of mobile terminals (such as mobile phones, laptops .) and, because of this, a wide collection of different terminal possibilities and terminal characteristics, it is difficult to create a mobile multimedia application which can be used on mobile devices of different types. In this paper, we propose a mobile multimedia application that adapts its content to the possibilities of the mobile terminal and to the end-user preferences. Also the application takes changing device characteristics into account. To make this possible, a software framework is set up to enable negotiation between the mobile terminal and the content server. During the initial negotiation, the concept of the Universal Multimedia Access framework is used. Subsequent negotiations take place after changing terminal characteristics or end-user preferences, and this by means of time-dependent metadata. This newly created flexible and extendable framework makes it possible that multimedia applications interact with the content provider in order to deliver an optimal multimedia presentation for any arbitrary mobile terminal at any given time.

Region-of-interest-based progressive transmission of gray-scale images across the Internet

On the Internet, transmission time of large images is still an important issue. In order to reduce transmission time this paper introduces an efficient method to send 8-bit greyscale images across the Internet. The method allows progressive transmission up to lossless reconstruction. It also allows the user to select a region of interest. This method is particularly useful when image quality and transmission speed are two desired properties. The method uses TCP-IP as a transport protocol.

Generic mapping mechanism between content description metadata and user environments

The number of terminals that have access to multimedia content by means of a network is rapidly increasing. More and more, the characteristics of different terminals are increasing in variety. In addition, their users can have different preferences. Therefore, the adaptation of multimedia content to a specific terminal and/or its user has become an important research issue. Such an adaptation is mainly based on two aspects: the description of the multimedia content and the description of the user environment. Both can be considered as metadata, and can be formatted in an XML language (e.g., MPEG-7 and CC/PP). However, it is not yet clear how we can realize a generic mapping mechanism between two such vocabularies. We feel that such a mechanism is necessary to accomplish a mature content adaptation framework. This paper describes how such a mechanism can be achieved. We attach requirements and preferences of the user environment to specific aspects of the description of multimedia content. Based on this information, we try to maximize the value of the adapted content, while making it appropriate for the terminal. We also take into account the extensibility of the existing vocabularies we focus on, because this means our mechanism will also be extensible.

Introducing streaming XML (SXML)

In the near future broadband networks will become available to large groups of people. The amount of bandwidth available to these users in the future will be much more than it is now. The availability of bandwidth will give birth to a number of new applications. Application developers will need a framework that enable them to utilize the possibilities of these new networks. In this article we present a document type that will allow the addition of (meta-) information to data streams and the synchronization of a different data streams. It is called SXML (Streaming XML) and is based on the eXtensible Markup Language (XML). The SXML grammar is defined in a document type definition (SXML-DTD). The content of an SXML document can be processed real time or can be retrieved from disk. XML is being used in a complete new manner and in a totally different environment in order to easily describe the structure of the stream. Finally, a preliminary implementation has been developed and is being tested.

Analysis of multimedia formats for content description

Among some of the most popular multimedia formats available today are: QuickTime, Shockwave, Advanced Streaming Format, RealVideo and {MPEG-4}. Since broadband Internet became widely available, these multimedia formats have strongly evolved and are extremely popular. This article analyzes these formats based on an existing reference model. This reference model is built on the state-of-the-art in three areas: temporal models, computer based descriptions and synchronization mechanisms. Out of these three areas a set of 10 criteria describing the reference model was created. In this paper we first shortly explain the reference model and its ten criteria. Then each of the listed multimedia formats is mapped onto the reference model. Finally, a comparison based on the reference model is given. In the conclusions section we point out some of the strong and some of the weak points for the different multimedia formats based on the comparison.

XML-based description and presentation of multimedia radiological data

An XML-based application was developed, allowing to access multimedia/radiological data over a network and to visualize them in an integrated way within a standard web browser. Four types of data are considered: radiological images, the corresponding speech and text files produced by the radiologist, and administrative data concerning the study (patient name, radiologists name, date, etc.). Although these different types of data are typically stored on different file systems, their relationship (e.g., image file X corresponds to speech file Y) is described in a global relational database. The administrative data are referred to in an XML file, while links between the corresponding images, speech, and text files (e.g., links between limited text fragments within the text tile, the corresponding fragment in the speech file, and the corresponding subset of images) are described as well. Users are able to access all data through a web browser by submitting a form-based request to the server. By using scripting technology, a HTML document containing all data is produced on the fly, which can be presented within the browser of the user. Our application was tested for a real set of clinical data, and it was proven that the goals that were defined above are realized.