[Bug 726521] v4l2src fails to enumerate Raspberry Pi camera which specifies stepwise frame sizes

[GStreamer (bugzilla.gnome.org)]

https://bugzilla.gnome.org/show_bug.cgi?id=726521
  GStreamer | gst-plugins-good | 1.2.3

--- Comment #6 from Nicolas Dufresne <nicolas.dufresne at collabora.co.uk> 2014-03-18 14:32:24 UTC ---
(In reply to comment #5)
> And a question, what I didn't understand, why is it necessary to probe all
> possible mode combinations ahead of time anyway?

That is also a good question that I need to look at. A lot of the GStreamer
V4L2 code has been implemented on top of broken drivers, so it may explain some
strange behavior. Though, these days, I want to encourage fixing drivers, and
have GStreamer implement as few quirks as possible.

> 
> If I ask for 640x480 at 60fps, why does it need to iterate through all of them
> to build these massive data structures? Why can't it just jump straight to that
> requested mode?

The iteration probably occurs before the element is aware of the downstream
caps. In general, an element need to probe the HW to offer a valid set of caps
in order to do the negotiation.

-- 
Configure bugmail: https://bugzilla.gnome.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the QA contact for the bug.
You are the assignee for the bug.