[whatwg] Start position of media resources

Jonas Sicking jonas at sicking.cc
Mon Apr 6 21:44:35 PDT 2009


On Mon, Apr 6, 2009 at 7:21 PM, Robert O'Callahan <robert at ocallahan.org> wrote:
> On Tue, Apr 7, 2009 at 3:40 AM, Eric Carlson <eric.carlson at apple.com> wrote:
>>
>>   A media file with a non-zero initial time stamp is not new to
>> oggz-chopped files (eg. an MPEG stream initial PTS can have any value, SMPTE
>> time-codes do not necessarily start at zero, etc) , but I disagree that we
>> need a new attribute to handle it.
>>   Media time values are expressed in normal play time (NPT), the absolute
>> position relative to the beginning of the presentation. It is the
>> responsibility of the UA to map time zero of the element to the starting
>> time of the media resource, whatever it may be.
>
>
> What if a script wants to present UI that contains the time from the media
> resource?

One alternative is to not solve this in this version of the element.
I'd say it depends on how common this type of videos are, and how bad
the UI experience is until we support this.

One thing is that even if we add a property like
"videoEncodedStartTime", most people are likely to never make use of
it due to not knowing that it exists. Is that a problem?

/ Jonas



More information about the whatwg mailing list