- From: Ian Hickson <ian@hixie.ch>
- Date: Tue, 7 Jul 2009 07:55:12 +0000 (UTC)
- To: "Michael A. Puls II" <shadow2531@gmail.com>, Simon Pieters <simonp@opera.com>, Robin Berjon <robin@berjon.com>, Jonas Sicking <jonas@sicking.cc>
- Cc: "public-html@w3.org" <public-html@w3.org>
On Mon, 22 Jun 2009, Michael A. Puls II wrote: > > If you load <video> on some site and just want to hear the audio, is > there a way to turn off the video output so you can save some cpu and > just listen to the audio? If you mean for the user: the browser should be able to offer you that choice, if they think that's something users will want. It's up to the browser vendor. If you mean for the author: just use <audio>, or display:none the <video> element (or remove it from the document). Browsers can then optimise the case of the video not showing. On Tue, 23 Jun 2009, Simon Pieters wrote: > > > > If not, I think that would be totally awesome if you could do that > > (wish youtube and all the other video sites did that). > > > > Something like video.toggleVideoOutput() so the site can provide a > > button. > > The page can set video.hidden to do this. <video hidden> means the video isn't relevant, so that's probably not really the right semantic if the audio is still wanted. On Tue, 23 Jun 2009, Michael A. Puls II wrote: > > display: none in Firefox seems to cut the cpu usage. But, I'm not sure > if it cuts all activity with the video renderer or not. visibility: > hidden doesn't seem to work for cutting the cpu usage much, but probably > should. I recommend reporting such issues directly to your browser vendor. > You just mean a class selector that sets display: none for example? That would work, yes. On Tue, 23 Jun 2009, Simon Pieters wrote: > > <Hixie> zcorpan_: technically <video hidden> means "this isn't relevant" > and so we should probably make it mute the audio as well > > The spec does not currently say this at the moment. > > I haven't thought about this enough to have an opinion on whether it > would be a good thing or not to mute the audio. I don't think we should do this (the same as we don't actually prevent form controls marked as hidden="" from submitting). On Tue, 23 Jun 2009, Jonas Sicking wrote: > > We'd also have to mute if any ancestor was hidden. Yeah, it could get complicated. It would also mean hidden="" was more complicated to implement than just one line of CSS. On Wed, 24 Jun 2009, Robin Berjon wrote: > > The way I see it, semantically, <video> has an implied <audio> component > (for lack of a better word) since it plays both in AV. Based on that, it > would IMHO make sense to mute the audio when hidden (I would assume > audio would be muted for <audio hidden>). If you want audio only, use > <audio>. I think it would make sense, but isn't worth the extra complexity. It's one of those trade-offs between the theoretically correct pure model and the pragmatic easy-to-understand model. (Note that none of this affects display:none or completely removing the element from the tree, which should not affect audio playback.) -- Ian Hickson U+1047E )\._.,--....,'``. fL http://ln.hixie.ch/ U+263A /, _.. \ _\ ;`._ ,. Things that are impossible just take longer. `._.-(,_..'--(,_..'`-.;.'
Received on Tuesday, 7 July 2009 07:55:48 UTC