Changes

The aim here is to analyse as many requirements for attaching additional information to audio & video files for diverse purposes. Then we can generalise a framework for attaching such additional information, in particular to Ogg files/streams. And as a specialisation of this, we can eventually give solutions for captions and audio annotations in particular.

As an alternative to embedding some of this information into Ogg files, it is possible to keep them in a separate file and just refer to them as related to the a/v file. However, when we are talking about receiving a/v inside a Web browser (or more generally a Web client), we do not want to open a random number of connections to a Web server to receive an a/v stream. The aim is to receive exactly one stream of data and to have this stream of data flexibly include more or less additional information over the pure audio or video data. Also, video a11y should be the task of the video author, not the web page author.