RFC: gtk v4l2 (webcam) control panel app + applet

[Bastien Nocera]

On Fri, 2010-01-15 at 11:14 +0100, Hans de Goede wrote:
> Hi,
> 
> On 01/12/2010 01:13 PM, Bastien Nocera wrote:
> > Good idea, apart from:
> >
> > On Tue, 2010-01-12 at 12:39 +0100, Hans de Goede wrote:
> >>
> >> For Fedora-14 (to be released November 2010) it would be nice to have
> >> a
> >> gtk application for controlling various camera settings (brightness,
> >> contrast, etc.) *and* a small applet which shows a webcam icon
> >> next to the clock when a webcam is present.
> >
> > Having an applet showing up for each and every type of device that's
> > plugged into your computer is a bad idea.
> >
> 
> I agree, but I have a number of reasons for thinking this way (note this
> is not me saying but I'm going to go this way anyways, this is me asking
> for better ways to achieve the below aims):
> 
> 1. Many people don't know which app to use to test their webcam, one of
> the things I would also like to add to the icon is "launch webcam viewer"
> (this is a bit of a lame reason, if this were the only one, the icon could
>   die right away).

A "webcam" preference would probably be good enough.

> 2. One some laptops the webcam can be turned on / off with Fn + F##, and
> there is no indicator whether it is on or off, the icon would serve as
> such an indicator.

You'd add a visual cue to gnome-settings-daemon, this is already what we
do for a number of the multimedia keys. Feel free to file an upstream
bug with some details about that key combination (whether it's hard
wired, whether there's X key events happening when you do that and what
it is, etc.).

> 3. Some really cheap still cameras, so called dual mode cams, can also
> functions as a webcam, but only when the gvfs gphoto2 share in nautilus
> is not mounted, this icon is supposed to tell people that:
> 1) A webcam was detected (even if the kernel driver at that moment was detached
> by gvfsd-gphoto2)
> and:
> 2) Give them easy access to unmounting the gphoto2 share, making the camera
> available to other apps.

This is really a work-around for bugs in the way our framework works.
Something like that would probably do:
https://bugzilla.gnome.org/show_bug.cgi?id=606058

> So making the list myself I guess that for 2. we could make the icon optional,
> defaulting to off (to be configurable from the capplet) and for 3. we could
> opt to only show the icon be default for these types of cameras.
> 
> Note 3 is a hard problem, because of the mix of userspace and kernelspace
> drivers for the 2 functions and them both using the same usb interface
> on the device (these devices usually only have one interface).
> 
> > Having a well-made capplet (a dialogue for the control-center) would be
> > a better fit. It should obviously handle hotplugging.
> 
> Ack, that is a good idea.

Cheers