2277 Web Video Text Tracks (WebVTT) Format Text (Structured) WebVTT files are used for captioning or subtitling video content. It is a standard created by the World Wide Web Consortium (W3C) for displaying timed text, and is linked to the HTML5 <track> element. The primary purpose of WebVTT files is to add text overlays to a video. Each time interval is specified in the format (HH:)mm:ss.xxx --> (HH:)mm:ss:xxx e.g. 00:00.000 --> 00:02.310 or 01:00:05.000 --> 01:00:07.000. The (HH:) is optional, but if included must have a minimum of 2 digits representing the hour (more than 2 digits may be used), and where both the minute (mm) and second (ss) parts must be between 00 and 59 inclusive. 249 LIBNOVA / LIBNOVA 16 Nov 2020 13 Mar 2023 fmt/1454 PUID text/vtt MIME vtt File extension 1819 Web Video Text Tracks (WebVTT) Absolute from beginning of file, offset 0-4, magic bytes: WEBVTT {10-40} then a time stamp in the format xx:xx.xxx followed by --> {0-5} followed by xx:xx.xxx (where x is a number). 1 Absolute from BOF 0 4 574542565454{5-400}[30:35][30:39]3A[30:35][30:39]2E[30:39][30:39][30:39]202D2D3E20{0-5}[30:35][30:39]3A[30:35][30:39]2E[30:39][30:39][30:39]