W3C home > Mailing lists > Public > public-media-fragment@w3.org > January 2010

ISSUE-14 (davy): How to deal with embedded time stamps

From: Media Fragments Working Group Issue Tracker <sysbot+tracker@w3.org>
Date: Thu, 28 Jan 2010 15:21:01 +0000 (GMT)
To: public-media-fragment@w3.org
Message-Id: <20100128152101.0978D4DD6E@crusher.w3.org>

ISSUE-14 (davy): How to deal with embedded time stamps

http://www.w3.org/2008/WebVideo/Fragments/tracker/issues/14

Raised by: Davy Van Deursen
On product: 

The current spec shortly mentions media with embedded time stamps. However, more information should be provided regarding how to deal with embedded time stamps. Currently, three questions arise:

- is there a different behavior in using NPT vs. SMPTE time addressing and if so, under which circumstances (e.g., are SMPTE time codes embedded in the media resource or not)?

- do we take into account the timing information of the media (usually specified in the underlying container format) when extracting temporal media fragments? For example, suppose a certain track 'a' of a media file ex.mp4 plays from 5s to 10s and from 20s to the end. What will be the result of interpreting ex.mp4#track='a'&t=0,15 ?

- in case of a media fragment Range request, what should be returned in the response header? More specifically, is the instance length optional or mandatory per the Content-Range header syntax?

Further reading:
* initial mail from Werner: http://lists.w3.org/Archives/Public/public-media-fragment/2010Jan/0027.html
* Silvia elaborating on SMPTE time codes: http://lists.w3.org/Archives/Public/public-media-fragment/2010Jan/0059.html
* Raphaƫl's summary: http://lists.w3.org/Archives/Public/public-media-fragment/2010Jan/0075.html
Received on Thursday, 28 January 2010 15:21:05 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Wednesday, 21 September 2011 12:13:37 GMT