On Oct 16, 2008, at 9:24 AM, Dr. Markus Walther wrote:
Eric Carlson wrote:
I agree that it is more work to implement a custom controller, but
it
seems a reasonable requirement given that this is likely to be a
relatively infrequent usage pattern.
How do you know this will be infrequent?
Of course I don't *know* that 'start' and 'end' attributes will be
used infrequently, but I suspect it based on my experience helping
developers with the QuickTime plug-in. It has had 'startTime' and
'endTime' attributes for almost ten years, but they are not commonly
used.
Or do you think that people will frequently want to limit playback
to
a section of a media file?
Yes, I think so - if people include those folks working with
professional audio/speech/music production. More specifically the
innovative ones among those, who would like to see audio-related web
apps to appear.
Imagine e.g. an audio editor in a browser and the task "play this
selection of the oscillogram"...
Why should such use cases be left to the Flash 10 crowd
(http://www.adobe.com/devnet/flash/articles/dynamic_sound_generation.html)?
I for one want to see them become possible with open web standards!
I am anxious to see audio-related web apps appear too, I just don't
think that including 'start' and 'end' attributes won't make them
significantly easier to write.
In addition, cutting down on number of HTTP transfers is generally
advocated as a performance booster, so the ability to play sections
of a
larger media file using only client-side means might be of independent
interest.
The 'start' and 'end' attributes, as currently defined in the spec,
only limit the portion of a file that is played - not the portion of a
file that is downloaded. If you are interested in clients requesting
and playing media fragments, you might want to look at the W3C Media
Fragments Working Group [1] which is investigating this issue.
eric
[1] http://www.w3.org/2008/WebVideo/Fragments
