Nested Context Language - AbsoluteAstronomy.com

Nested Context Language (NCL) is a declarative authoring language for hypermedia

Hypermedia

Hypermedia is a computer-based information retrieval system that enables a user to gain or provide access to texts, audio and video recordings, photographs and computer graphics related to a particular subject.Hypermedia is a term created by Ted Nelson....

documents.

NCL is an XML

XML

Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

application language, which provides several facilities for authoring a complete hypermedia document with synchronization relationships among its components. Among its main facilities, it treats hypermedia relations as first-class entities through the definition of hypermedia connectors, and it can specify arbitrary semantics for a hypermedia composition using the concept of composite templates.

Following others XML standards, NCL is specified by a modular approach. NCL modules can be added to standard web languages, such as XLink

XLink

XML Linking Language, or XLink, is an XML markup language and W3C specification that provides methods for creating internal and external links within XML documents, and associating metadata with those links.-The XLink specification:...

and SMIL

Synchronized Multimedia Integration Language

SMIL , the Synchronized Multimedia Integration Language, is a W3C recommended XML markup language for describing multimedia presentations. It defines markup for timing, layout, animations, visual transitions, and media embedding, among other things...

.

NCL was initially designed for the Web environment, but currently it is included as the declarative language of the Japanese-Brazilian ISDB-Tb

ISDB-Tb

ISDB-Tb is the short for International System for Digital Broadcast, Terrestrial, Brazilian version.It is a Digital TV system based on Japanese ISDB-T . ISDB-Tb system is also known as SBTVD and is used in Brazil...

(International Standard for Digital Broadcasting) terrestrial DTV (digital TV) middleware (named Ginga

Ginga (SBTVD Middleware)

Ginga is the middleware specification for the Brazilian Digital TV System . Ginga was developed based on a set of standardized technologies, such as ITU-T J.200, and also adding innovations developed by Brazilian researchers...

). It is also the first standardized technology of the ITU-T

ITU-T

The ITU Telecommunication Standardization Sector is one of the three sectors of the International Telecommunication Union ; it coordinates standards for telecommunications....

multimedia application framework series of specifications for IPTV

IPTV

Internet Protocol television is a system through which television services are delivered using the Internet protocol suite over a packet-switched network such as the Internet, instead of being delivered through traditional terrestrial, satellite signal, and cable television formats.IPTV services...

services.

Enhanced Digital TV profile (EDTV)

NCL 3.0 Enhanced DTV profile includes the Structure, Layout, Media, Context, MediaContentAnchor, CompositeNodeInterface, PropertyAnchor, SwitchInterface, Descriptor, Linking, CausalConnectorFunctionality, ConnectorBase, TestRule, TestRuleUse, ContentControl, DescriptorControl, Timing, Import, EntityReuse, ExtendedEntityReuse, KeyNavigation, Animation, TransitionBase, Transition and Metainformation modules of NCL 3.0.

NCL Basic Digital TV profile (BDTV)

Includes almost all Enhanced Digital TV profiles but it doesn't include Animation, TransitionBase and Transition modules.

NCL 3.0 Modules

NCL is partitioned in functional areas. Each functional area groups a set of related modules. NCL 3.0 functional areas and modules are:

Structure
- Structure Module
Layout
- Layout Module
Components
- Media Module
- Context Module
Interfaces
- MediaContentAnchor Module
- CompositeNodeInterface Module
- PropertyAnchor Module
- SwitchInterface Module
Presentation Specification
- Descriptor Module
Linking
- Linking Module
Connectors
- ConnectorCommonPart Module
- ConnectorAssessmentExpression Module
- ConnectorCausalExpression Module
- ConnectorTransitionAssessment Module
- CausalConnector Module
- CausalConnectorFunctionality Module
- ConnectorBase Module
Presentation Control
- TestRule Module
- TestRuleUse Module
- ContentControl Module
- DescriptorControl Module
Timing
- Timing Module
Reuse
- Import Module
- EntityReuse Module
- ExtendedEntityReuse Module
Navigational Key
- KeyNavigation Module
Animation
- Animation Module
SMIL Transition Effects
- TransitionBase Module
  Note: The TransitionBase Module is defined by NCL 3.0. SMIL 2.0 doesn't define this module.
- BasicTransition Module
- TransitionModifers Module
SMIL Meta-Information
- Metainformation Module

External links

NCL Players

GINGA-NCL Reference Implementation, available under GPLv2 (in Portuguese).
GHTV GINGA-NCL player for Windows and Linux under Creative Commons
Creative Commons licenses
Creative Commons licenses are several copyright licenses that allow the distribution of copyrighted works. The licenses differ by several combinations that condition the terms of distribution. They were initially released on December 16, 2002 by Creative Commons, a U.S...

Attribution-NonCommercial-NoDerivs 3.0 License (in Portuguese).

Authoring tools

NCL Eclipse official website (in Portuguese)