w3c/imsc (imscJS & imscHRM)
Description
Reference repo for the IMSC TTML profiles, hosting imscJS (web renderer/polyfill) and imscHRM (Hypothetical Render Model validator).
Resource details
- Category path
- Standards & Industry›Closed Captioning & Subtitling Standards
- Classification
- Not yet classified
w3c/imsc (imscJS & imscHRM) is cataloged in Standards & Industry and Closed Captioning & Subtitling Standards.
URL
Related resources
- IMSC 1.2 — TTML Profiles for Internet Media Subtitles and CaptionsLatest stable W3C spec text for IMSC 1.2, the base standard behind most subtitle delivery in streaming.
- TTML Live Extensions ModuleW3C spec for live TTML/EBU-TT-Live subtitle streaming extensions, niche companion to IMSC.
- W3C IMSC Test SuiteOfficial IMSC1 conformance test suite; several tests double as EBU-TT-D conformance tests.
- Netflix Timed Text Style GuidesNetflix's official hub of subtitle/caption style guide requirements and per-language templates, an industry-standard captioning reference.
- EBU Tech 3380: EBU-TT-D Subtitling Distribution FormatEBU's TTML-based subtitling distribution format spec designed for DASH/OTT delivery.
- MPEG-5 Standards Overview (EVC & LCEVC)Overview of MPEG-5 Part 1 (EVC) and Part 2 (LCEVC) codec standards with links to specifications.
- MPEG Basics (Chiariglione)Explanation of MPEG standardization process and organizational structure by MPEG founder Leonardo Chiariglione.
- Disney Dolby Vision Best Practices Guide v1.3.1Official Disney mastering spec detailing Dolby Vision L0/L1/L2/L5/L6/L8 metadata layers and trim requirements per content type.
- Video Coding Experts Group (VCEG)Overview of ITU-T's Video Coding Experts Group and its joint work with MPEG (JVET) developing codecs beyond VVC.
- Dolby Vision Overview (Technical PDF)Vendor-style technical overview of Dolby Vision mastering workflow covering PQ grading, CMU, and trim metadata.
- HbbTV Reference ApplicationMIT-licensed reference DASH player with PlayReady/Marlin/ClearKey test material including cbcs streams, from the official HbbTV Association.
- Dolby.io Media APIs — Developer ToolsOfficial Dolby.io reference documentation for Media APIs developer tooling.
- Netflix Dolby Vision HDR Mastering GuidelinesOfficial Netflix delivery specification for Dolby Vision mastering, covering DV 4.0/2.9 profile requirements and IMF packaging.
- SMPTE ST 2110 — Professional Media over Managed IP NetworksOfficial SMPTE standard page for ST 2110, the professional media-over-IP suite (2025 Emmy-winning standard with EBU and VSF).
- AIMS Alliance (Alliance for IP Media Solutions)Industry alliance driving adoption of open IP standards (SMPTE ST 2110, NMOS) for professional media infrastructure interoperability.