stereo_proc NO subscription so NO stereo_images

edit

Hi everybody

I was wondering if someone has ever seen something like that.

I'm using two uEye USB camera with a personnal arduino trigger. Everything works fine. The calibration setup is OK. But when I try to launch the stereo_proc node, I can clearly see with rxgraph (or rosnode info) that stereo/proc as no subscriptions. And according to the stereo_image_proc tutorial I should have

Subscriptions:

• /stereo/left/image_raw [sensor_msgs/Image]

• /stereo/left/camera_info [sensor_msgs/CameraInfo]

• /stereo/right/image_raw [sensor_msgs/Image]

• /stereo/right/camera_info [sensor_msgs/CameraInfo]

And I'm thinking that's why I can not go further with the my stereo bench.

Here is my launch file.

<launch>
 <!-- first camera and associated image pipeline -->

  <group ns="stereo_test" >
    <!-- left camera -->
        <node pkg="cameraUEYE" type="cameraUEYE_node" name="cameraUEYE_left_node" >
            <param name="guid" value="1" />
            <param name="frame_id" value="cam_left" />
            <param name="use_ros_time" value="true" />
            <param name="use_external_trigger" value="true" />
            <param name="frame_rate" value="50" />
                    <param name="camera_info_url" value="file:///home/vvittori/.ros/camera_info/UEYE_USB_1.yaml"/>
        <remap from="camera" to="left" />
        </node>
  <!-- right camera -->
        <node pkg="cameraUEYE" type="cameraUEYE_node" name="cameraUEYE_right_node" >
            <param name="guid" value="2" />
            <param name="frame_id" value="cam_right" />
            <param name="use_ros_time" value="true" />
            <param name="use_external_trigger" value="true" />
            <param name="frame_rate" value="50" />
                    <param name="camera_info_url" value="file:///home/vvittori/.ros/camera_info/UEYE_USB_2.yaml"/>
        <remap from="camera" to="right" />
        </node>
<!-- STEREO IMAGE PROC -->
<node pkg="stereo_image_proc" type="stereo_image_proc" respawn="false" name="proc" args="_approximate_sync:=True" />  
  </group>
  <!-- monitoring and configuration tools -->
  <node pkg="rxtools" type="rxconsole" name="rxconsole" />
  <node pkg="dynamic_reconfigure" type="reconfigure_gui"
        name="reconfigure_gui" /> 
</launch>

Any hints are welcomed !

Thanks

Regards

EDIT :

Thanks to Patrick I was able to understand that part in the wiki page ! (Cf. Patrick answer) I was still block at the rosnode info stereo/proc results that they give us.

Anyway I've tried what he told me with the following command line (I have change stereo_test to stereo in my launch file)

ROS_NAMESPACE=stereo rosrun stereo_image_proc stereo_image_proc __name:=PROC

and

rosrun image_view stereo_view stereo:=/stereo image:=image_rect

as written in the wiki page. Then, I did see what you told me that right after I launch the previous command it subscribed at

[ INFO] [1334565947.793592670]: Subscribing to:
    * /stereo/left/image_rect
    * /stereo/right/image_rect
    * /stereo/disparity

and yet I had the following error that occured :

OpenCV Error: Assertion failed (0 <= roi.x && 0 <= roi.width && roi.x + roi.width <= m.cols && 0 <= roi.y && 0 <= roi.height && roi.y + roi.height <= m.rows) in Mat, file /tmp/buildd/libopencv-2.3.1+svn6514+branch23/modules/core/src/matrix.cpp, line 303
OpenCV Error: Assertion failed (0 <= roi.x && 0 <= roi.width && roi.x + roi.width <= m.cols && 0 <= roi.y && 0 <= roi.height && roi.y + roi.height <= m.rows) in Mat, file /tmp/buildd/libopencv-2.3.1+svn6514+branch23/modules/core/src/matrix.cpp, line 303
terminate called after throwing an instance of 'cv::Exception'
  what():  /tmp/buildd/libopencv-2.3.1+svn6514+branch23/modules/core/src/matrix.cpp:303: error: (-215) 0 <= roi.x && 0 <= roi ...