w3c/imsc (imscJS & imscHRM)

Reference repo for the IMSC TTML profiles, hosting imscJS (web renderer/polyfill) and imscHRM (Hypothetical Render Model validator).

Link

• Visit resource

Related resources

• bbc/ttml-validatorValidates TTML documents against constraint sets including BBC Subtitle Guidelines, IMSC Text, EBU-TT-D, and DAPT profiles.
• IMSC Text Profile 1.3 (W3C)W3C specification defining the IMSC 1.3 TTML2 text profile for worldwide subtitle/caption exchange, with validation and presentation requir…
• ADM-OSC — ADM object metadata over OSCOpen spec and tools mapping ADM (Audio Definition Model) object metadata onto OSC for live/broadcast immersive audio interop.
• ETSI EN 300 743: DVB Subtitling SystemsOfficial DVB bitmap subtitling standard covering region/CLUT/object composition for broadcast PES-based subtitle delivery.
• FAB ESUB-XF Specification (EBU-STL Successor)European Subtitle Exchange Format spec mapping legacy EBU-STL (Tech 3264) into XML.
• MPEG-B Part 7: Common Encryption (CENC) overviewMPEG's own free overview page for ISO/IEC 23001-7 Common Encryption, explaining cenc/cbc1/cens/cbcs schemes.
• Cable BibleA guide to cables and connectors used for audiovisual tech
• ITU-R BT.2100-3 — Image Parameter Values for HDR-TVLatest (Feb 2025) official ITU-R recommendation defining PQ and HLG transfer functions and HDR-TV image parameters for production/exchange.
• Report ITU-R BT.2408-5 — Operational Practices for HDR TV ProductionOfficial ITU-R guidance report on HDR TV production operational practices: gamma/exposure handling, best-practice workflows.
• Ultra HD Forum GuidelinesIndustry guidelines produced by the Ultra HD Forum, covering end-to-end workflows for Ultra HD content (4K, HDR, Wide Color Gamut, Next-Gen…