MatroskaWebVTT: Difference between revisions

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(→‎Questions: webvtt uses the term 'cue timings')
(→‎DRAFT: 'cue text' is 'cue payload' for metadata tracks)
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  - CodecID is S_WEBVTT
  - CodecID is S_WEBVTT
  - File-header metadata, if any, is included verbatim in CodecPrivate
  - File-header metadata, if any, is included verbatim in CodecPrivate
  - cue text is included verbatim in the Block data
  - cue text/payload is included verbatim in the Block data
  - timestamp and BlockDuration as set from the cue timestamps
  - timestamp and BlockDuration as set from the cue timestamps



Revision as of 16:40, 27 January 2012

DRAFT

[WebVTT] is a subtitle/text track format developed for the HTML5 media element and related applications. This is a proposal for how to encapsulate such tracks in the Matroska/WebM container.

WebVTT is based on the .srt format, effectively the simplest text track format is use, so we can make use of the [Matroska mapping for SRT] as a starting point.

- CodecID is S_WEBVTT
- File-header metadata, if any, is included verbatim in CodecPrivate
- cue text/payload is included verbatim in the Block data
- timestamp and BlockDuration as set from the cue timestamps

The sequence number and presentation attributes from the cue header are not represented.

Questions

It would be nice to represent the presentation attributes. How do to that?

Would be be easier to embed the complete cue as is? The parser has to handle this from javascript. The Matroska subtitle guidelines recommend against including the cue timings in the packet data because it makes it harder to edit the file.