ARToolKit can't identify usb camera

Question

I have instaled ARToolKit on Ubuntu 12.10 on a 64bit Asus. The install gave no errors so I think I'm ok. But when I want to try one af the examples it can't find the camera. If I don't fill anything in at char *vconf = ""; I get

No video config string supplied, using defaults.
ioctl failed

The most often found solution implies char *vconf = "v4l2src device=/dev/video0 use-fixed-fps=false ! ffmpegcolorspace ! capsfilter caps=video/x-raw-rgb,width=640,height=480 ! identity name=artoolkit ! fakesink";

But this doesn't work for me. I get

r@r-K55VD:~/Downloads/Artoolkit-on-Ubuntu-12.04-master/bin$ ./simpleTest
Using supplied video config string [v4l2src device=/dev/video0 use-fixed-fps=false ! ffmpegcolorspace ! capsfilter caps=video/x-raw-rgb,width=640,height=480 ! identity name=artoolkit ! fakesink].
ARVideo may be configured using one or more of the following options,
separated by a space:

DEVICE CONTROLS:
 -dev=filepath
    specifies device file.
 -channel=N
    specifies source channel.
 -noadjust
    prevent adjusting the width/height/channel if not suitable.
 -width=N
    specifies expected width of image.
 -height=N
    specifies expected height of image.
 -palette=[RGB|YUV420P]
    specifies the camera palette (WARNING:all are not supported on each camera !!).
IMAGE CONTROLS (WARNING: every options are not supported by all camera !!):
 -brightness=N
    specifies brightness. (0.0 <-> 1.0)
 -contrast=N
    specifies contrast. (0.0 <-> 1.0)
 -saturation=N
    specifies saturation (color). (0.0 <-> 1.0) (for color camera only)
 -hue=N
    specifies hue. (0.0 <-> 1.0) (for color camera only)
 -whiteness=N
    specifies whiteness. (0.0 <-> 1.0) (REMARK: gamma for some drivers, otherwise for greyscale camera only)
 -color=N
    specifies saturation (color). (0.0 <-> 1.0) (REMARK: obsolete !! use saturation control)

OPTION CONTROLS:
 -mode=[PAL|NTSC|SECAM]
    specifies TV signal mode (for tv/capture card).

What is a methodological way of finding out what exactly to put at char *vconf = " " ?Because I feel I tried a lot of variations at random, but nothing works. I know it needs a path like /dev/video0, but what else seems up in the air to me.

Answer 1

char *vconf = "v4l2src device=/dev/video0 use-fixed-fps=false !
ffmpegcolorspace ! capsfilter
caps=video/x-raw-rgb,width=640,height=480 ! identity name=artoolkit !
fakesink";

The above configuration you tried is for GStreamer driver. Since you are using VideoLinuxV4L , instead of the above use:

char *vconf = "-dev=/dev/video0 ";

For more you can refer to "{ARtoolkit Folder}/doc/video/index.html"