- From: Stefan Håkansson LK <stefan.lk.hakansson@ericsson.com>
- Date: Wed, 20 Nov 2013 17:41:36 +0000
- To: Martin Thomson <martin.thomson@gmail.com>, Jan-Ivar Bruaroey <jib@mozilla.com>
- CC: "public-media-capture@w3.org" <public-media-capture@w3.org>
On 20/11/13 18:27, Martin Thomson wrote: > On 20 November 2013 08:17, Jan-Ivar Bruaroey <jib@mozilla.com> wrote: >> Shouldn't we first nail down what min and max mean? e.g. > > This I agree with. But the answer might not be as deterministic as > you might like. > >> - Does { mandatory: { width: { min: 1024 } } } conservatively give me >> 1024x768 >> or the highest available because I didn't constrain upward? >> >> - Does { mandatory: { width: { max: 2880 } } } aggressively give me >> 2880x1800 >> or the lowest available because I didn't constrain downward? >> >> - Given choices, what does { mandatory: { width: { min: 1024, max: 2880 } } >> } give me? I'm going to throw in one more thing here (relevant only to width/height/aspect): how do we relate this to the width and height of the consumer? Say a video MediaStreamTrack with mandatory setting of width min 1024 is only attached to a video element with a width of 200. Should the camera really produce a stream with width 1024, only to have it scaled at display time? > > The answer to these is universally, "I don't know". And I think that > I am perfectly comfortable with that. > >> I think we need to establish default behavior of the algorithm here (please >> point me to it if this is already done). > > I disagree. Obviously, we would like to have a situation where the > "best" source is selected, but that is a multi-dimensional > optimization problem that the browser is required to manage. Then > there is user preference thrown in. > > When you get down to it, constraints on selection are just additional > input into the selection algorithm that the browser chooses to > implement. > > Given that, I think that it would be folly to specify an algorithm to > the extent that different browsers produce identical results for all > variations of constraints and sources. There's a place for > standardization, but I don't think that this is it. > > I don't think that having additional preferences is necessary. That > is the function that optional constraints fulfill already. Having > more ways to influence the selection algorithm is only going to make > it harder to build and understand. I worry that we are already in > that situation; let's not make it worse. > > (Actually, I do like the "prefer" suggestion. But it's duplicative, > so I'd be interested only if you also remove optional constraints at > the same time. I consider that to be an unlikely outcome at this > stage.) > >
Received on Wednesday, 20 November 2013 17:42:00 UTC