[libavg-devel] video4Linux2 on libavg: some design choices

[Ulrich von Zadow]

Hi,

looks like everything is coming along very well :-).

Do you think you can check a version that works and doesn't break
anything old into subversion before the weekend? Then I'll try it here,
maybe fix firewire if that's necessary and see if I can commit the stuff
that you've done to trunk.

Some more comments are inline. I'll have a longer look this weekend.

OXullo Intersecans schrieb:

> <camera id="cam" x="0" y="0" width="640" height="480"
> device="/dev/video0" mode="640x480_YUV422" channel="1" source="v4l" />
> 
> attributes are quite self-explanatory however:
> 
> mode: WxH_PF where PF can be: RGB, MONO8, YUV422 (the same as firewire
> camera)
> channel: video mux selector, for example, a bt878 pci board has:
> 0=tuner, 1=composite, 2=svideo
> source: 'v4l' instead of 'firewire' is the magic switch

Looks good. The 'mode' attribute seems a bit strange to me in the v2l
case, but I don't have any good idea how to change it.

> Now, about the tracker.
> This is instantiated by Player, using addTracker() method, usually as
> python binding Player.addTracker()
> 
> We split this method in two: addFWTracker(device, mode) and
> addV4LTracker(device, mode, channel). This seems not to be the best way,
> but was the fastest, waiting for some Uli's advices basing on his best
> flavours.

Yeah, that doesn't seem like we want it to stay that way. I'll look at
the code over the weekend.

> We have some doubts about avgtrackerrc.
> The one supplied with mtc subproject (TrackerConfig.xml) does not
> validate against the trackerconfig dtd, as the latter requires a more
> detailed structure.

Ok, I'll fix that...

> At this time, V4LCamera does not honour tune-in attributes, therefore
> the <camera> node of the rc is simply ignored.

Are you going to implement that? If not, we should throw an error if the
camera node is there.

cu,

  Uli