Re: getCapabilities() as both static and object method?

In alternative A, won't the unknown mandatory constraints fail in gUM 
before  the permissions prompt is reached?  Would  the UA ever prompt 
the user for devices with properties that it doesn't understand?
On 5/15/2014 4:09 AM, Harald Alvestrand wrote:
> On 05/15/2014 02:35 AM, Jan-Ivar Bruaroey wrote:
>> On 5/13/14 3:41 AM, Harald Alvestrand wrote:
>>> The need as identified  is to know what constraints are recognized by
>>> the platform before calling getUserMedia (that is, before we have any
>>> instances to call the function on).
>>
>> Would this method return just the constraint names understood by this 
>> UA or actual values?
>
> If it has the same syntax as the current one, names and values.
>
>>
>> If the latter, what values? Some union (or intersection?) of all 
>> camera capabilities on a user's system?
>
> My thinking: Union of capabilities - the range of values that it 
> doesn't make sense to go outside.
> You will have corner cases (max 320x200 camera, HD camera that can't 
> go below 640x480), but I can't think of anything that makes more sense 
> than "union".
>
>>
>> getUserMedia is prescriptive, and unknown mandatory constraints fail, 
>> so I don't see why we need this method.
>
> Yes, it's possible to do this by probing.
> However, I can see three different dialogues resulting, only one of 
> which I like:
>
>
> --- Alternative A, mandatory constraints
>
>   [ Grab the camera! ]
>     [x] Use the depth channel
>     [x] Use the IR channel
>     [x] Use the front camera
>
> ---- hit the button
>
>    Sorry, I don't understand what "IR channel" means
>
> ---- swear, unmark, hit the button
>
>    Sorry, I don't understand what "depth channel" means
>
> --- swear, unmark, hit the button
>
>    Sorry, I don't have any "front" camera.
>
> --- with the patience of an angel, remove the last checkbox and hit 
> the button again
>
>   Welcome! Here's your camera!
>
> --- Alternative B, optional constraints
>
>   [ Grab the camera! ]
>     [x] Use the depth channel
>     [x] Use the IR channel
>     [x] Use the front camera
>
> --- hit the button
>    Welcome! Here's your camera!
>    I know you asked for "front", "IR" and "depth", but it seems that 
> this camera is facing in some
>    random direction, and I don't understand the rest of your question, 
> so I ignored it.
>
> --- Alternative C, pre-filtering
>
>   [ Grab the camera! ]
>
> --- hit the button
>
>    Welcome! Here's your camera!
>
>
>>
>> .: Jan-Ivar :.
>>
>
>

-- 
Jim Barnett
Genesys

Received on Thursday, 15 May 2014 13:37:05 UTC