Re: PROPOSAL: Simple image capture API

On 03/15/2012 12:40 AM, Robert O'Callahan wrote:
> On Tue, Mar 13, 2012 at 5:01 PM, Randell Jesup <randell-ietf@jesup.org 
> <mailto:randell-ietf@jesup.org>> wrote:
>
>     On 3/13/2012 4:17 AM, Anant Narayanan wrote:
>
>         I'm trying to avoid a dependency on MediaStreams for the
>         particular case where all the web page wants is a single image
>         from the user's camera. Profile pictures, QR codes, there
>         might be more…
>
>
> But you almost always want a preview, and that often needs to be 
> app-specific, even for profile pictures and QR codes, so I think 
> MediaStreams are usually needed anyway.
>
> I don't think we want to propagate events along MediaStreams. That 
> doesn't seem necessary.
>
> I think it would make sense to have VideoMediaStreamTrack (like 
> AudioMediaStreamTrack already), and APIs on video tracks to request 
> setting of various camera parameters (resolution, focus mode, etc) 
> (async of course), and an API to request a snapshot with/without flash 
> and various other parameters set momentarily (also async). The 
> snapshot API should probably trigger a callback passing a Blob which 
> can be used as an <img> source.

I kind of dislike talking about the flash property of a 
VideoMediaStreamTrack. It's another one of those things that don't make 
sense in the 90% case (remote stream, stream from file, stream from 
video camera without flash).

If we adopt Anant's proposal with a specific "head of chain" object, I 
think the flash belongs up there.

              Harald