[whatwg] Html 5 video element's poster attribute

Silvia Pfeiffer silviapfeiffer1 at gmail.com
Sun Sep 19 15:17:57 PDT 2010

On Mon, Sep 20, 2010 at 6:53 AM, Shiv Kumar <skumar at exposureroom.com> wrote:

>  I’d like to see the implementation of the poster attribute change to
> something that is more useful. By useful I mean something that wroks without
> the need for javascript and works the way most people would expect.
> Currently the poster disappears as soon as the first frame has been
> downloaded, which typically takes a second. The player then shows this first
> frame, but 99% of the time the first frame is black. So what you see is a
> black box.

Not quite: this is an implementation decision that Webkit-based browsers
made. Neither Opera nor Firefox work that way (haven't checked IE yet).

I agree that this implementation of poster frames is practically useless and
it really annoys me as a user. I've been considering registering a bug on
Webkit. However, there is a loophole in the spec that allows for this
behaviour - the video element section states:
"When a video<http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#video>element
the current
playback position<http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#current-playback-position>is
the first frame of video, the element
the frame of video corresponding to the current
playback position<http://www.whatwg.org/specs/web-apps/current-work/multipage/video.html#current-playback-position>or
the poster
at the discretion of the user agent."

The first half of the either...or... statement is really annoying and should
be removed.

>  The poster frame of a video is probably the most important not only for
> the viewer but also for the content producer. It’s the one shot the content
> producer gets at enticing the viewer to watch her video. Most video websites
> therefore provide multiple ways in which the content producer can define a
> poster frame for her video.
> As a result of the current behavior you’ll see that most html video player
> implementation don’t set the source attribute on the video element, so as to
> prevent the poster from disappearing or some will overlay an image over the
> video element. Ideally, one should be able to simply use the video tag to
> get the expected behavior without having to go through hoops.
> The solution would be the following:
> The poster frame should remain visible until the video is played.
> The poster should not show while the player is seeking (some browser
> implementation do show the poster while seeking, resulting a flashes)

I agree with changing the spec to require this behaviour.

>  The poster should show again after the video has ended.

I think this would be confusing and would prefer it it just stays at
displaying the last played frame. That gives users the visual queue that the
playback has finished.

> The visibility of the poster should be scriptable and/or controllable using
> an attribute. Meaning that one should be able to turn on/off the poster
> (without changing the poster attrbute’s value)

Is this really necessary? What would be the use case? Either you want to
poster - then you provide the attribute - or you don't want it - then you
don't provide it. Also, per script you can remove the attribute and reset
it, if you really need it. I don't see what an extra attribute would add?

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.whatwg.org/pipermail/whatwg-whatwg.org/attachments/20100920/dbfb8df0/attachment-0002.htm>

More information about the whatwg mailing list