IEC 62298-3:2005 - TeleWeb application - Part 3: Superteletext profile (Overview)
IEC 62298-3:2005 specifies the TeleWeb Superteletext profile, a presentation-layer profile that enables Web-style text and graphics to be broadcast and displayed on suitable TV decoders. The standard defines the format, attributes and content conventions for a TeleWeb service - a collection of multimedia data files designed to be lightweight and TV-friendly. It focuses on TeleWeb HTML implementation, graphical requirements (colours, fonts, layout) and content formats while delegating transport and delivery details to IEC 62298‑1 and IEC 62298‑2.
Key topics and technical requirements
- Presentation layer (TeleWeb HTML): Defines a restricted HTML-like syntax and document structure optimized for TV decoders, including supported tags, headers, paragraphs, character formatting and hypertext links.
- Display and graphics: Rules for colour representation, font metrics, text placement, image representation and support for 4:3 and 16:9 aspect ratios. Annexes include a default colour palette and font metrics.
- File and URL schemes: Naming conventions, TeleWeb file reference schemes, Teletext and nexTView reference handling, and special-function URLs for TV-centric navigation.
- Images and content formats: Specification of image file types and usage (e.g., GIF, JPEG) and guidance on embedding graphics for decoders.
- Default styling and compatibility: A default TeleWeb style (including an informative CSS2 style sheet) and a TeleWeb Document Type Definition (DTD) to promote consistent rendering across decoders.
- Metadata and attributes: Service-related and file-related attributes, content labelling (themes, parental ratings), scheduling and storage attributes to support broadcasting environments.
- Interoperability guidance: Annex material and a reference decoder profile to help implementers validate compliance.
Practical applications and who uses it
IEC 62298-3 is intended for practitioners delivering Web-like content to television platforms:
- Broadcasters and content providers: Create TeleWeb services synchronized with TV programs, EPG enhancements and interactive overlays.
- Decoder and set-top box manufacturers: Implement TeleWeb HTML rendering, default styles, palette and resource handling to ensure consistent user experience.
- Middleware and software developers: Build authoring tools, encoders and playback engines that generate TeleWeb-compliant files and URLs.
- System integrators and service operators: Manage service metadata, parental controls, scheduling and delivery attributes for broadcast ecosystems.
- Standards bodies and certification labs: Use the profile, DTD and reference decoder guidance for interoperability testing and compliance verification.
Related standards
- IEC 62298-1 - TeleWeb general description and system overview
- IEC 62298-2 - Delivery methods and transport layer specifics
- IEC 62298-4 - Hyperteletext profile (in preparation at time of publication)
Keywords: IEC 62298-3, TeleWeb, Superteletext, TeleWeb HTML, presentation layer, decoder, Teletext, multimedia data files, colour palette, font metrics, TV broadcasting, set-top box.