RE: Implementation Report for mediafragments.js

Hi Thomas,

Thanks for the update of your library. The TC0072-UA is now working.

I partially agree on adhering what the input was for NTP times. Then it
leaves the job of dealing with specific time format to the actual player
based on the video resources. But in my situation, I always have to get the
seconds (actually it's milliseconds) in order to set the starting position
of the player. So I have to convert npt-hhmmss, npt-mmss and smpte formats
to seconds. In the previous version of your library, npt:00:00:03 will be
returned as 3(s) and I don't need to do any more process about this
information.  But if the return of npt format also include npt-hhmmss
format, I then have to parse this result  to get the seconds. Maybe the best
way is to add another parameter to indicate what format you want to return
when calling the parse method, such as:

MediaFragments.parseMediaFragmentsUri(uriStr, "seconds")

This is only my situation and maybe I didn't realise other conditions. I am
not sure if Ninsuna Player has similar issue? 

Regards
Yunjia Li

PhD Student & Research Fellow
Web and Internet Science Group
School of Electronics and Computer Science 
The University of Southampton 
Southampton SO17 1BJ 
http://afterglowlee.blogspot.com


-----Original Message-----
From: Thomas Steiner [mailto:tomac@google.com] 
Sent: 17 November 2011 14:41
To: Yunjia Li
Cc: Davy Van Deursen; Erik Mannens; Media Fragment
Subject: Re: Implementation Report for mediafragments.js

Hi all,

I have fixed the bug where trailing dots in NPT were not recognized
properly. On the way I have found two further erroneous test cases, which
Davy has corrected already (see the separate thread for that [1]).

I have also added SMPTE "start < end" checks, which were not yet contained
in the previous release. Again on the way I found that in one test case we
had incorrect SMPTE time specifications, Davy has also corrected the test
case already (again, in a different thread [2]).

In summary, implementation testers might want to have another look at the
test cases
1) TC0019-UA
2) TC0026-UA
3) TC0080-UA
4) TC0081-UA

Please note that the library used to normalize NPT times like 00:00:10
(hh:mm:ss) to 10 (s), which it no longer does. As @currentTime [3] in
<audio> and <video> expects time in seconds, we might default back to the
initial normalized behavior, however, with non-NPT time specifications this
is not possible, so I thought in order to avoid confusion, I strictly adhere
to what the input was, as long it is a valid NPT time. Thought?

Best,
Tom

[1]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Nov/0019.html
[2]
http://lists.w3.org/Archives/Public/public-media-fragment/2011Nov/0037.html
[3] http://www.w3.org/TR/html5/video.html#dom-media-currenttime

--
Thomas Steiner, Research Scientist, Google Inc.
http://blog.tomayac.com, http://twitter.com/tomayac

Received on Thursday, 17 November 2011 16:07:24 UTC