- From: Thierry MICHEL <tmichel@w3.org>
- Date: Mon, 04 Oct 2010 17:07:46 +0200
- To: Thomas Steiner <tomac@google.com>
- CC: "public-media-annotation@w3.org" <public-media-annotation@w3.org>
Thomas, Thank you for your response. After reading your email, I have changed the status of your Comments to "Commenter approved disposition". Best, Thierry Le 04/10/2010 16:59, Thomas Steiner a écrit : > Hi Thierry, hi Work Group members, > > Thank you for your detailed response! Please find my comments below. > >> 1) Subtitles >> >> Concerning external subtitles, using ma:relation is the correct approach as >> in your example. The identifier attribute contains the URL of the subtitle >> file, and the relation type qualifies it as a subtitle relation. The value >> should be a URI, but could also be a string. It is recommended to use a >> controlled vocabulary for the type of the relation. > This is perfectly what I was hoping for. Agreed. > >> Embedding of subtitles is not a use case that we considered, however it is >> possible. The mechanism we use to specify timed metadata is to specify >> fragments identified by Media Fragment URIs [1] and then describe >> annotations of these fragments. > Same here. Agreed. > >> - Link to external subtitle file using ma:fragment, with type subtitle and a >> Timed Text Markup Language (TTML) [2] or WebSRT [3] file as target. > Assuming ma:fragment is actually ma:relation. Agreed. > >> - Subtitles can be embedded in a media file, in which case they can be >> described as a track media fragment using ma:fragment and Media Fragment >> URIs [1]. > This sounds like a nice and flexible way. Agreed. > >> - Subtitles could be embedded by using ma:title with a type qualifier for >> subtitle. A list of time media fragments is defined and each fragment is >> annotated using ma:title. > This, while possible, sounds like an overcharge of what ma:title was > designed for. Personally I'd not go this way. > >> Although the last option is a way of embedding subtitles that is not a use >> case we considered. We expect that in most cases a dedicated format such as >> TTML or WebSRT will be used for the subtitles and referenced. > Agreed. TTML and WebSRT are both very good standards. > >> 2) Semantic annotation >> >> As described above, time based annotations are a possible. Currently, two >> cases are covered by the spec: >> >> - use ma:description for a textual description of the media resource (or a >> fragment) > Possible, but not machine-readable/understandable by default. > >> - use ma:relation to link to a RDF file or named graph containing the >> annotation for the media resource (or fragment) > Good solution. Especially when used with ma:fragment this has the > potential and degree of freedom of expression that I need. Agreed. > >> There is currently no solution for embedding a set of triples into one of >> the ma:* properties. We understand that might be useful and have started >> discussion with the Semantic Web Coordination Group about a solution for >> this problem (see thread starting at [3]). The summary of the discussion is: >> Named graphs could be a solution to this issue, but there is no standard >> syntax for expressing them, to which our specification could refer. Such a >> syntax might find its way into RDF 2.0. As no other applicable solution >> emerged in the discussion, we decided to exclude the embedding of triples >> into ma:* elements until a standard syntax for named graphs is available. > Let's continue the discussion of [3] (the 2nd [3] ;-) below the first > [3]) at [3]. > > Cheers, > Tom >
Received on Monday, 4 October 2010 15:08:26 UTC