Hi Thad,

[...]
> > > start streaming when you need an image. You can stop streaming right
> > > after getting the data, and start again later when required by your
> > > application.
> >
> > Laurent, I think Thad was talking about actual still image support (UVC
> > standard, section 2.4.2.4), which can - if the camera supports it -
> > provide better quality than the streaming modes.
>
> Yes, this is exactly right.  The QC notebook pro can capture a still
> image at 1.3 megapixel, much better than any single frame when it
> is streaming.  This is one of the few webcams that can produce stills
> of that quality that and is definitely the smallest I've found.  That is
> important for my application; I plan to suspend it on a flexible arm
> over my drafting table to use it as part of my animation toolchain.

The good news is the QC notebook pro can capture video at 1.3 megapixel as 
well :-) All UVC webcams I am aware of implement still image capture method 
1, which means they don't implement still image capture at all (method 1 
emulates still image capture in software).

> > It would be great if you could actually implement that. We've had
> > discussions about how best to do it before and didn't actually reach a
> > conclusion. My personal favorite is this: dd if=/dev/video0
> > of=mystillpicture.jpg
> >
> > If that's in the spirit of V4L2 or not is probably subject to discussion
> > and there are several other ways to do it, so if you want to have a go,
> > we'll be happy to help.

That's on my todo list, but I currently lack hardware to test this on. Is 
anyone aware of a webcam implementing still image capture method 2 or method 
3 ?

Cheers,

Laurent Pinchart
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