Tt/Timed Text Efforts

This page has been donated to the Timed Text Working Group and updates can now be found in the Timed Text wiki.

• Timed Text in MPEG 4 (http://mpeg.chiariglione.org/standards/mpeg-4/timed-text-and-other-visual-overlays-iso-base-media-file-format)

WebVTT-based efforts and specifications

• Specifications(http://dev.w3.org/html5/webvtt/)
  • Getting Started With the Track Element (http://www.html5rocks.com/en/tutorials/track/basics/)
  • Introduction to WebVTT and <track> (http://dev.opera.com/articles/view/an-introduction-to-webvtt-and-track/)
  • WebVTT in WebM (http://wiki.webmproject.org/webm-metadata/temporal-metadata/webvtt-in-webm)
  • 608/708 mapping (https://dvcs.w3.org/hg/text-tracks/raw-file/669f6b95a488/608toVTT/608toVTT.html)
  • WebVTT in Apple’s HTTP Live Streaming (http://tools.ietf.org/html/draft-pantos-http-live-streaming-11)

• Implementations
  • IE 10: http://ie.microsoft.com/testdrive/Graphics/VideoCaptions/Default.html
  • Chrome: http://www.iandevlin.com/blog/2012/06/html5/google-chrome-supports-webvtt-subtitles
  • Opera: my.opera.com/desktopteam/blog/2012/08/03/summer-core-update
  • Firefox: making progress https://bugzilla.mozilla.org/show_bug.cgi?id=629350

• JavaScript polyfills for backwards compatibility (http://www.w3.org/community/texttracks/2012/08/23/webvtt-support-in-browsers/)

• Validator (http://quuz.org/webvtt/)

TTML-based efforts and specifications

• SMPTE ST 2052-1 aka SMPTE-TT (https://www.smpte.org/sites/default/files/st2052-1-2010.pdf)
  • developed by SMPTE (http://smpte.org)
  • worldwide text- and image-based captions
  • mapping from CEA 608 to SMPTE-TT (https://www.smpte.org/sites/default/files/rp2052-10-2012.pdf)
  • mapping from CEA 708 to SMPTE-TT (upcoming)

• CFF-TT (latest published version at http://uvvu.com/docs/public/tspec/CFFMediaFormat-1.0.5.pdf)
  • based on SMPTE TT (ST 2052-1)
  • developed by DECE (http://uvvu.com)
  • worldwide text- and image-based captions and subtitles

• TTML Simple Delivery Profile for US Captions (http://www.w3.org/TR/ttml10-sdp-us/)
  • developed by the W3C TTML WG
  • intended to be a subset of CFF-TT

• EBU-TT (http://tech.ebu.ch/ebu-tt)

• CEA (http://www.ce.org/)
  • Closed Captioning in IP-delivered Video Programming (http://www.ce.org/Standards/Standard-Listings/R4-3-Television-Data-Systems-Subcommittee/CEA-TR-3.aspx

• YouView (https://industry.youview.com/resources/YouView_Core_Technical_Specification_1.0.pdf#page=118)