Marcio Ferreira Moreno

Ginga-NCL: the declarative environment of the Brazilian digital TV system

As in all main terrestrial DTV Systems, the Brazilian middleware, named Ginga, supports both declarative applications (through its presentation, or declarative, environment Ginga-NCL) and procedural applications (through its execution, or procedural, environment Ginga-J). Since hybrid applications are common, either type of Ginga application may make use of facilities of both presentation and execution application environments. This paper focuses on the presentation environment Ginga-NCL. The main Brazilian inovations are then presented, regarding the Ginga architecture, the declarative NCL language specification, the editing commands for live application production, and the transport data structure.

Ginga-NCL: Declarative middleware for multimedia IPTV services

This article presents the innovative features of Ginga-NCL, an open middleware specification for multimedia IPTV services. Ginga-NCL relies on the Nested Context Language, a domain-specific declarative language targeting multimedia application authoring. As a glue language, NCL relates media objects in time and space without restricting or imposing any media content type, including media objects with imperative and declarative code written using other languages. Other NCL features include support for multidevice presentations, content adaptations, presentation adaptations, and advanced code reuse. Ginga-NCL allows NCL applications to be modified on the fly by means of live editing commands. Initially defined as the standard middleware for the Brazilian terrestrial DTV system, Ginga-NCL has recently become part of ISDB standards and an ITU-T Recommendation for IPTV services.

Live editing of hypermedia documents

In some hypermedia system applications, like interactive digital TV applications, authoring and presentation of documents may have to be done concomitantly. This is the case of live programs, where not only some contents are not known a priori, but also some temporal and spatial relationships, among program media objects, may have to be established after the unknown content definition. This paper proposes a method for hypermedia document live editing, preserving not only the presentation semantics but also the logical structure semantics defined by an author. To validate this proposal, an implementation has been done for the Brazilian Digital TV System, which is also presented.

Multiple exhibition devices in DTV systems

Nested Context Language (NCL) is the declarative language of the Brazilian Terrestrial Digital TV System. NCL is part of ISDB (International Standard for Digital Broadcasting) standards and also the ITU-T Recommendation H.761 for IPTV services. This paper presents, discusses, and illustrates the NCL hierarchical control model for multiple exhibition device support. Based on this model, multiple devices are orchestrated to run a DTV application in cooperation. Two types of multiple device exhibitions are distinguished. Those where the same content is shown in a set of devices under a unique control, and those where content is under each individual device control, working completely independent. In this last case, depending on viewer interactions, the resulting presented content can differ from a device to another. Examples of NCL applications using both options are presented and discussed.

NCM 3.1: A Conceptual Model for Hyperknowledge Document Engineering

Most of multimedia documents available today are agnostic to data semantics and their specification language offer little to ease authoring and mechanisms to their players so they can retrieve and present meaningful content to improve user experience. In this paper, we present the main entities of the version 3.1 of the Nested Context Model (NCM), which concentrate efforts at integrating support for enriched knowledge description to the model. This extension enables the specification of relationships between knowledge descriptions in the traditional hypermedia way, composing what we call hyperknowledge in this paper. NCM previous version (NCM 3.0) is a conceptual model for hypermedia document engineering. NCL (Nested Context Language), which is part of international standards and ITU recommendations, is an XML application language that was engineered according to NCM 3.0 definitions. The extensions discussed in this paper contribute not only for advances in the NCL specifications, but mainly as a conceptual model for hyperknowledge document engineering.

Interleaved Time Bases in Hypermedia Synchronization

Unsolicited interleaved media content is common in digital TV systems, particularly in broadcast TV, in which advertisements are inserted into programs transmitted sequentially. Although certain existing middleware systems address this problem, their solutions have limitations. This work proposes an alternative approach that provides high-level event-based abstractions that hide or minimize the complexity of dealing with interleaved media content as part of hypermedia applications. This article discusses how multimedia languages and players can handle multiple time bases in supporting intermedia synchronization with interleaved media content. The proposal has been incorporated in the Nested Context Language (NCL) and in its player, the main component of the Ginga digital TV middleware. This approach can also be adapted to be used in other languages and engines.

Ginga‐NCL architecture for plug‐ins

Ginga is the middleware of the Japanese‐Brazilian terrestrial digital TV (DTV) system, ISDB‐T B, and also the ITU Telecommunication Standardization Sector (ITU‐T) Recommendation for Internet Protocol television services. Ginga supports NCL (Nested Context Language) applications in its declarative environment (Ginga‐NCL) for which we devise an architecture for plug‐in integration. This paper focuses on this plug‐in architecture and its innovative solutions, detailing the plug‐in API, life‐cycle and control model, besides discussing how the architecture can be extended to other software systems, in particular to other DTV middleware systems. In the paper, we show how Ginga‐NCL can embed other declarative language engines. On the other hand, we also extend an HTML browser to allow it to embed Ginga‐NCL. This proof‐of‐ concept is important because NCL and HTML players are not only the most common players found in DTV middleware systems but also because they are ITU Telecommunication Standardization Sector Recommendations for terrestrial and Internet Protocol television services (NCL and Broadcast Markup Language (BML)/Lightweight Interactive Multimedia Environment (LIME)). Therefore, this proof‐of‐concept also provides a contribution to DTV middleware interoperability. Copyright

Ginga-NCL: implementaçao de referência para dispositivos portáteis

This paper aims to present the first reference implementation of Ginga-NCL for portable receivers. Although based on a particular platform, the implementation not only works as a concept proof, but also raised several issues that should be taken into account when embedding this system. Ginga is the standard middleware of the Brazilian Digital TV System and Ginga-NCL is the unique required environment for portable devices.

Resilient hypermedia presentations

This paper proposes a recovery plan for Ginga-NCL, the declarative middleware environment of the Japan-Brazilian Digital TV Standard and ITU-T Recommendation for IPTV services. The proposed plan aims at providing resilience to digital TV presentations. As proof of concept, the recovery plan has been incorporated to the Ginga-NCL reference implementation. However, it can also be applied to other DTV middlewares.

Ginga-NCL: supporting multiple devices

Multimedia applications for DTV systems can take profit of multiple exhibition devices to enrich the set of supported interactive applications. New applications in which viewers can cooperate besides being able to have its own navigation space without disturbing their neighbors in a common environment will now be possible. The NCL language allows developing such applications following a hierarchical model supported by its presentation environment called Ginga-NCL, by using a set of components in charge of orchestrating the several devices used in the presentation. This paper presents the mentioned support provided by the reference implementation of the Ginga-NCL middleware, stressing its architecture and illustrating the new possibilities opened by the multi-device applications.