[whatwg] Start position of media resources

[David Singer]

At 22:30  +1000 9/04/09, Silvia Pfeiffer wrote:
>On Thu, Apr 9, 2009 at 4:46 AM, Ian Hickson <ian at hixie.ch> wrote:
>>  On Wed, 8 Apr 2009, David Singer wrote:
>>>  >
>>>  > Navigation outside the indicated range could be done in several ways -
>>>  > it does not have to be through indicating the full length of the
>>>  > resource in the timeline.
>>>
>>>  surely.  but which one can the URL/page author expect?  If I pick an
>>>  innocuous scene out of an R-rated movie and put it on a web page for
>>>  children, can they easily see other parts of the movie or not?
>>
>>  I think the answer to this should be "yes".
>
>I agree thus far.
>
>>  For example if someone on
>>  reddit links to a particular part of a video, as a user I should trivially
>>  (by dragging the scrubber) be able to see the context. I don't think we
>>  should be changing the timeline just because the author set a start and
>>  end position somehow.
>
>I understand that this makes sense in a lot of cases - e.g. in
>something like http://www.youtube.com/watch?v=kHXuXWznFgk#t=5s .
>
>However, I would actually prefer if we make the full resource
>available in a different manner. The reason is that when you link to a
>small segment that is part of a long resource - e.g. 30 seconds out of
>a 5 hour long video - your selection on the timeline is not visible
>and it is unclear where the segment is playing and you're unable to
>scrub around the segment properly.
>
>Maybe we can introduce a toggle button that allows the timeline to
>show/hide context, in particular for long resources? Or we could
>introduce a attribute that says context="true/false" depending on what
>the page author prefers is being done with the segment? This would
>also allow to hide the context in cases such as the one that David
>described. Not that it can be completely hidden - anyone who
>understands URLs will be able to load the full resource. But it will
>make it more difficult.

I think the spec. merely needs to say that the UA focuses the initial 
attention of the user on this segment of the media resource, and 
should optimize network usage to that end;  but neither the UA nor 
the user are restricted to this section if they don't wish to be. 
How they handle that, how good their navigation/scroll-bar etc. is, 
is up to them in this case - we've said as much as we need to for the 
author and server to know what's happening.
-- 
David Singer
Multimedia Standards, Apple Inc.