Thanks for your reply,finally i solved that problem,but there is a new one now

This morning i started with this tutorial:
http://www.hitl.washington.edu/artoo...n/devmulti.htm
The problem is that after build my marker i cannot train the pc on that marker.
In that guide i should do:
./mk_patt
Enter camera parameter filename: (i put the path of file camera_para.dat)
I receive this answer:
Usin supplied video config string [videotestsrc].
libARvideo:GStreamer 0.10.36
(mk_patt:5146):Glib-GObject-WARNING**:invalid cast from 'GstVideoTestSrc' to 'GstBin'
(mk_patt:5146):GStreamer-CRITICAL **:gst_bin_get_by_name:assertion 'GST_IS-BIN (bin)' failed
pipeline has no element named 'artoolkit'!
setupCamera():Unable to open connection to camera.
main():unable to set up AR camera
I hope you have a solution for this problem!!!
Thanks for your help