After an evaluation, GNOME has moved from Bugzilla to GitLab. Learn more about GitLab.
No new issues can be reported in GNOME Bugzilla anymore.
To report an issue in a GNOME project, go to GNOME GitLab.
Do not go to GNOME Gitlab for: Bluefish, Doxygen, GnuCash, GStreamer, java-gnome, LDTP, NetworkManager, Tomboy.
Bug 506682 - [v4lsrc] creates wrong caps on the source pad (width and height range)
[v4lsrc] creates wrong caps on the source pad (width and height range)
Status: RESOLVED OBSOLETE
Product: GStreamer
Classification: Platform
Component: gst-plugins-base
git master
Other Linux
: Normal normal
: git master
Assigned To: GStreamer Maintainers
GStreamer Maintainers
Depends on:
Blocks:
 
 
Reported: 2008-01-01 13:13 UTC by Thijs Vermeir
Modified: 2010-11-05 08:37 UTC
See Also:
GNOME target: ---
GNOME version: ---


Attachments
add fixed resolutions from vcap (2.12 KB, patch)
2008-01-01 16:47 UTC, Thijs Vermeir
needs-work Details | Review

Description Thijs Vermeir 2008-01-01 13:13:53 UTC
The v4lsrc sets the width and the height in the caps as a range between the min and max resolution of the device. However this width and height can't be a random set between this two values. but must be a fixed set of resolutions like (174x144, 40x480)

In reverse caps negotiation the wrong caps can be selected and therefore crash the v4l device.
Comment 1 Thijs Vermeir 2008-01-01 13:27:35 UTC
That second resolution needs to be 640x480 :-)
Comment 2 Thijs Vermeir 2008-01-01 16:47:56 UTC
Created attachment 101941 [details] [review]
add fixed resolutions from vcap

This patch adds fixed resolutions (min and max) for the v4l device.
Comment 3 Sebastian Dröge (slomo) 2008-10-08 11:52:49 UTC
Hm, so it's always just two resolutions that are supported by v4l? Without knowing anything about v4l it seems more likely that there are a fixed number of resolutions between this max and min and there should be some way to get them ;)
Comment 4 Thijs Vermeir 2008-10-08 12:21:31 UTC
Indeed there can be some more fixed resolutions defined between min and max values. This patch just prevents crashing because of the false caps with setting the caps too restrictive...

I also don't know much about v4l so don't know if this assumptions are true... 
Comment 5 Tobias Mueller 2009-04-23 13:00:40 UTC
Hey Sebastian, you set this bug to NEEDINFO with comment #3. I guess, the question has been answered in comment #4 and I am thus reopening.
Comment 6 Sebastian Dröge (slomo) 2009-05-07 12:37:18 UTC
Right, the questions are answered but there's still no better solution ;)
Comment 7 Janne Grunau 2010-11-05 08:34:39 UTC
I think this bug can be closed. The v4l2src now queries available frame size if the driver supports VIDIOC_ENUM_FRAMESIZES.

If it doesn't VIDIOC_S_FMT will return with a different frame size. That will be reported as an error in gst_v4l2_object_set_format().