camerabin throws an error in gst_camerabin_capture_start gstcamerabin.c(4036)

I hit this same issue on my Natty desktop as well

Running with GST_DEBUG=2 ...

rick@rick-mini10v:~/Projects/quidgets/quickly/widgets$ GST_DEBUG=2 python web_cam_box.py
0:00:00.079447007 1812 0x9c799e0 WARN GST_REGISTRY gstregistry.c:1184:gst_registry_scan_path_level:<registry0> ignoring old plugin /usr/lib/gstreamer-0.10/libgstvalve.so which has been merged into the corelements plugin
** Message: pygobject_register_sinkfunc is deprecated (GstObject)
0:00:01.155537967 1812 0xa223b58 WARN default xoverlay.c:354:gst_x_overlay_set_xwindow_id:<autovideosink0-actual-sink-xvimage> Using deprecated gst_x_overlay_set_xwindow_id()

0:00:08.351641219 1812 0x9c799e0 WARN camerabin camerabinimage.c:620:gst_camerabin_image_link_elements:<camerabinimage0> linking element failed
0:00:08.351846865 1812 0x9c799e0 WARN camerabin gstcamerabin.c:1042:gst_camerabin_change_mode:<camera-source> state change failed
0:00:08.351947067 1812 0x9c799e0 WARN camerabin gstcamerabin.c:4036:gst_camerabin_capture_start:<camera-source> error: starting capture failed
Error: GStreamer encountered a general core library error. gstcamerabin.c(4036): gst_camerabin_capture_start (): /GstCameraBin:camera-source

Thanks for the report, i've send it to https://bugzilla.gnome.org/show_bug.cgi?id=645427 so the upstream developers can have a look to it, i'll keep the bug posted with comments/questions etc. Thanks again.

There's a few questions from the upstream folks:

1.) Please try with the latest GStreamer from the PPA.
2.) Fix some of the unrelated errors (remove stale
/usr/lib/gstreamer-0.10/libgstvalve.so, don't use deprecated api in
web_cam_box.py - gst_x_overlay_set_xwindow_id())
3.) Please attach the output from v4l-info and xvinfo.
4.) can you run gst-launch camerabin ?

May you please attach those logs to the report? i can forward those upstream later. Thanks again.

I have the same issue and figured out the cause of it (but not yet how to solve this). When you comment out the following line:

self.camerabin.set_property("image-encoder",gst.element_factory_make("pngenc", "png_encoder"))

it works fine, except that it'll save as jpeg then instead of png.

As for the questions:
1) The same thing happens with stock gstreamer from Natty as from gstreamer installed from the gstreamer-developers ppa

2) I commented out the following: imagesink.set_xwindow_id(self.video_window.window.xid), which made gstreamer creates its own window to show the webcam output. I also tried using a fakesink so that nothing is shown. Both methods don't fix this problem.

3) Going to attach those to this bug.

4) That works fine, I launched it and afterwards closed the window once I could view my webcam:
$ gst-launch camerabin
Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
Setting pipeline to PLAYING ...
New clock: GstSystemClock
ERROR: from element /GstCameraBin:camerabin0/GstAutoVideoSink:autovideosink0/GstXvImageSink:autovideosink0-actual-sink-xvimage: Output window was closed
Additional debug info:
xvimagesink.c(1311): gst_xvimagesink_handle_xevents (): /GstCameraBin:camerabin0/GstAutoVideoSink:autovideosink0/GstXvImageSink:autovideosink0-actual-sink-xvimage
Execution ended after 1695783781 ns.
Setting pipeline to PAUSED ...
Setting pipeline to READY ...
Setting pipeline to NULL ...
Freeing pipeline ...

Thanks for the info titeuf!, I've already commented upstream, i'll keep in touch.

it's not clear that the bug even exists anymore, but even if it does, I don't see it getting fixed reasonably. Setting to won't fix as we shouldn't even spend time evaluating if it's still valid.