$ gst-launch-0.10 gconfvideosrc  ! queue ! videoscale ! videoflip ! autovideosink
Setting pipeline to PAUSED ...
ERROR: Pipeline doesn't want to pause.
ERROR: from element /pipeline0/gconfvideosrc0/bin0/v4l2src0: Could not negotiate format
Additional debug info:
gstbasesrc.c(2359): gst_base_src_start (): /pipeline0/gconfvideosrc0/bin0/v4l2src0:
Check your filtered caps, if any
Setting pipeline to NULL ...
FREEING pipeline ...