WapTV



         


WapTV is an interactive TV technology platform comprising a microbrowser, a markup language, and a significant collection of associated software tools and services. Further information, training and support is available from the WAP Forum WML 1.3 specification. The waptv microbrowser is currently available only as an OpenTV application, although an MHP version of the waptv browser has been built for demonstration and proof of concept. An emulator exists, based on Craftwork's, STBe OpenTV middleware emulation, but ongoing licensing issues between OpenTV and Craftwork prevent its distribution.

The WTVML markup language is a heavily extended superset of the WAP Forum WML 1.3 specification. WML content originally designed for wireless delivery to mobile phone handsets will work without modification on the Sky Interactive waptv platform, with the exception that any WBMP images will not appear on the Sky Interactive waptv microbrowser. WTVML version 6.1 was published as an ETSI standard in June 2004, and is now available for download from . The waptv schema definitions are available from . Errors, bugs, change and feature requests can be directed to the waptv Bugzilla at

The waptv browser and the wtvml markup language were originally developed by WAPTV Ltd. The company and its technology was acquired by British Sky Broadcasting in 2001. Platform development has continued within BSkyB, and version 7 of the waptv browser and WTVML markup language is due for release in Q3 2004. The waptv browser and WTVML markup is now the cornerstone of British Sky Broadcasting's interactive platform strategy.

The waptv platform brings internet-style content and interactivity to the Sky Digital platform by deploying a purpose-built WML microbrowser to the Sky Digital set-top-box over the satellite broadcast stream.

Services for the OpenTV based Microbrowser are written in WTVML, a superset of WML. The Sky Interactive microbrowser uses a standard 28.8Kbps modem to pull content across the online link. Because wtvml content is compiled into an encoded format by the OLS before transmission, it must be decoded on the set-top-box before it can be drawn to the screen. For optimal performance it is recommended that wtvml files (decks) for download are no more than 70K in size, with individual cards within each deck no more than 5K in size. When fully loaded, the browser comprises three separate virtual layers, devoted to MPEG & JPG still image presentation, MPEG video presentation and OnScreen Display (OSD) presentation respectively.

Developers can combine modes to produce very rich and diverse interactive TV interfaces. Multiple modes can be defined as a modeset. Different modes in the modeset can be referenced from the WML cards and associated with service domains, allowing the browser to change its style as the user navigates from one service to another. A modeset is a collection of one or more modes defined in a standalone XML file. A modeset is referenced at deck level from the mode attribute of the wml element. A developer can define multiple modes within a single modeset, and can initiate changes between Modes within that Modeset at card level.

The microbrowser can access Broadcast Resources as well as online resources delivered from a WML enabled Web server. Broadcast Resources are content elements that are delivered in the satellite broadcast stream.

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