[ttml1] Clock-time form time expressions allow 60 seconds for media timebase

nigelmegitt has just created a new issue for 
https://github.com/w3c/ttml1:

== Clock-time form time expressions allow 60 seconds for media 
timebase ==
There appears to be no restriction on the use of a value of `60` in 
the seconds component of a clock-time time expression of the form 
hh:mm:ss. When using `ttp:timeBase="media"` it therefore appears that 
a minute can have 61 seconds; my understanding of the use case for 
this is to accommodate UTC leap seconds, so I would expect a 
restriction that the `60` seconds value can only apply when 
`ttp:timeBase="clock"`, and possibly additionally when 
`ttp:clockMode="utc"|"local"` since GPS clocks are not adjusted for 
leap seconds.

Please view or discuss this issue at 
https://github.com/w3c/ttml1/issues/210 using your GitHub account

Received on Wednesday, 20 April 2016 11:26:21 UTC